[RFC 00/16] KVM: selftests: Add tests for SEV, SEV-ES, and SEV-SNP guests

[RFC 00/16] KVM: selftests: Add tests for SEV, SEV-ES, and SEV-SNP guests

[Michael Roth]

These patches and are also available at:

  https://github.com/mdroth/linux/commits/sev-selftests-rfc1

They are based on top of v5 of Brijesh's SEV-SNP hypervisor patches[1]
to allow for SEV-SNP testing and provide some context for the overall
design, but the SEV/SEV-ES patches can be carved out into a separate
series as needed.

== OVERVIEW ==

This series introduces a set of memory encryption-related parameter/hooks
in the core kselftest library, then uses the hooks to implement a small
library for creating/managing SEV, SEV-ES, SEV-SNP guests. This library
is then used to implement a basic boot/memory test that's run for all
variants of SEV/SEV-ES/SEV-SNP guest types, as well as a set of SEV-SNP
tests that cover various permutations of pvalidate/page-state changes.

- Patches 1-7 implement SEV boot tests and should run against existing
  kernels
- Patch 8 is a KVM changes that's required to allow SEV-ES/SEV-SNP
  guests to boot with an externally generated page table, and is a
  host kernel prequisite for the remaining patches in the series.
- Patches 9-12 extend the boot tests to cover SEV-ES
- Patches 13-16 extend the boot testst to cover SEV-SNP, and introduce
  an additional test for page-state changes.

Any review/comments are greatly appreciated!

[1] https://lore.kernel.org/linux-mm/20210820155918.7518-1-brijesh.singh@amd.com/

----------------------------------------------------------------
Michael Roth (16):
      KVM: selftests: move vm_phy_pages_alloc() earlier in file
      KVM: selftests: add hooks for managing encrypted guest memory
      KVM: selftests: handle encryption bits in page tables
      KVM: selftests: set CPUID before setting sregs in vcpu creation
      KVM: selftests: add support for encrypted vm_vaddr_* allocations
      KVM: selftests: add library for creating/interacting with SEV guests
      KVM: selftests: add SEV boot tests
      KVM: SVM: include CR3 in initial VMSA state for SEV-ES guests
      KVM: selftests: account for error code in #VC exception frame
      KVM: selftests: add support for creating SEV-ES guests
      KVM: selftests: add library for handling SEV-ES-related exits
      KVM: selftests: add SEV-ES boot tests
      KVM: selftests: add support for creating SEV-SNP guests
      KVM: selftests: add helpers for SEV-SNP-related instructions/exits
      KVM: selftests: add SEV-SNP boot tests
      KVM: selftests: add SEV-SNP tests for page-state changes

 arch/x86/include/asm/kvm-x86-ops.h                 |   1 +
 arch/x86/include/asm/kvm_host.h                    |   1 +
 arch/x86/kvm/svm/svm.c                             |  22 ++
 arch/x86/kvm/vmx/vmx.c                             |   8 +
 arch/x86/kvm/x86.c                                 |   3 +-
 tools/testing/selftests/kvm/.gitignore             |   2 +
 tools/testing/selftests/kvm/Makefile               |   3 +
 tools/testing/selftests/kvm/include/kvm_util.h     |   8 +
 tools/testing/selftests/kvm/include/x86_64/sev.h   |  70 ++++
 .../selftests/kvm/include/x86_64/sev_exitlib.h     |  20 ++
 tools/testing/selftests/kvm/include/x86_64/svm.h   |  35 ++
 .../selftests/kvm/include/x86_64/svm_util.h        |   2 +
 tools/testing/selftests/kvm/lib/kvm_util.c         | 249 +++++++++-----
 .../testing/selftests/kvm/lib/kvm_util_internal.h  |  10 +
 tools/testing/selftests/kvm/lib/x86_64/handlers.S  |   4 +-
 tools/testing/selftests/kvm/lib/x86_64/processor.c |  30 +-
 tools/testing/selftests/kvm/lib/x86_64/sev.c       | 381 +++++++++++++++++++++
 .../testing/selftests/kvm/lib/x86_64/sev_exitlib.c | 326 ++++++++++++++++++
 .../selftests/kvm/x86_64/sev_all_boot_test.c       | 367 ++++++++++++++++++++
 .../selftests/kvm/x86_64/sev_snp_psc_test.c        | 378 ++++++++++++++++++++
 20 files changed, 1820 insertions(+), 100 deletions(-)
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
 create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
 create mode 100644 tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c

[RFC 01/16] KVM: selftests: move vm_phy_pages_alloc() earlier in file

[Michael Roth]

Subsequent patches will break some of this code out into file-local
helper functions, which will be used by functions like vm_vaddr_alloc(),
which currently are defined earlier in the file, so a forward
declaration would be needed.

Instead, move it earlier in the file, just above vm_vaddr_alloc() and
and friends, which are the main users.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/lib/kvm_util.c | 146 ++++++++++-----------
 1 file changed, 73 insertions(+), 73 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 10a8ed691c66..92f59adddebe 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1145,6 +1145,79 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
 	list_add(&vcpu->list, &vm->vcpus);
 }
 
+/*
+ * Physical Contiguous Page Allocator
+ *
+ * Input Args:
+ *   vm - Virtual Machine
+ *   num - number of pages
+ *   paddr_min - Physical address minimum
+ *   memslot - Memory region to allocate page from
+ *
+ * Output Args: None
+ *
+ * Return:
+ *   Starting physical address
+ *
+ * Within the VM specified by vm, locates a range of available physical
+ * pages at or above paddr_min. If found, the pages are marked as in use
+ * and their base address is returned. A TEST_ASSERT failure occurs if
+ * not enough pages are available at or above paddr_min.
+ */
+vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
+			      vm_paddr_t paddr_min, uint32_t memslot)
+{
+	struct userspace_mem_region *region;
+	sparsebit_idx_t pg, base;
+
+	TEST_ASSERT(num > 0, "Must allocate at least one page");
+
+	TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
+		"not divisible by page size.\n"
+		"  paddr_min: 0x%lx page_size: 0x%x",
+		paddr_min, vm->page_size);
+
+	region = memslot2region(vm, memslot);
+	base = pg = paddr_min >> vm->page_shift;
+
+	do {
+		for (; pg < base + num; ++pg) {
+			if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
+				base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
+				break;
+			}
+		}
+	} while (pg && pg != base + num);
+
+	if (pg == 0) {
+		fprintf(stderr, "No guest physical page available, "
+			"paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
+			paddr_min, vm->page_size, memslot);
+		fputs("---- vm dump ----\n", stderr);
+		vm_dump(stderr, vm, 2);
+		abort();
+	}
+
+	for (pg = base; pg < base + num; ++pg)
+		sparsebit_clear(region->unused_phy_pages, pg);
+
+	return base * vm->page_size;
+}
+
+vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
+			     uint32_t memslot)
+{
+	return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
+}
+
+/* Arbitrary minimum physical address used for virtual translation tables. */
+#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
+
+vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
+{
+	return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
+}
+
 /*
  * VM Virtual Address Unused Gap
  *
@@ -2149,79 +2222,6 @@ const char *exit_reason_str(unsigned int exit_reason)
 	return "Unknown";
 }
 
-/*
- * Physical Contiguous Page Allocator
- *
- * Input Args:
- *   vm - Virtual Machine
- *   num - number of pages
- *   paddr_min - Physical address minimum
- *   memslot - Memory region to allocate page from
- *
- * Output Args: None
- *
- * Return:
- *   Starting physical address
- *
- * Within the VM specified by vm, locates a range of available physical
- * pages at or above paddr_min. If found, the pages are marked as in use
- * and their base address is returned. A TEST_ASSERT failure occurs if
- * not enough pages are available at or above paddr_min.
- */
-vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
-			      vm_paddr_t paddr_min, uint32_t memslot)
-{
-	struct userspace_mem_region *region;
-	sparsebit_idx_t pg, base;
-
-	TEST_ASSERT(num > 0, "Must allocate at least one page");
-
-	TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
-		"not divisible by page size.\n"
-		"  paddr_min: 0x%lx page_size: 0x%x",
-		paddr_min, vm->page_size);
-
-	region = memslot2region(vm, memslot);
-	base = pg = paddr_min >> vm->page_shift;
-
-	do {
-		for (; pg < base + num; ++pg) {
-			if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
-				base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
-				break;
-			}
-		}
-	} while (pg && pg != base + num);
-
-	if (pg == 0) {
-		fprintf(stderr, "No guest physical page available, "
-			"paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
-			paddr_min, vm->page_size, memslot);
-		fputs("---- vm dump ----\n", stderr);
-		vm_dump(stderr, vm, 2);
-		abort();
-	}
-
-	for (pg = base; pg < base + num; ++pg)
-		sparsebit_clear(region->unused_phy_pages, pg);
-
-	return base * vm->page_size;
-}
-
-vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
-			     uint32_t memslot)
-{
-	return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
-}
-
-/* Arbitrary minimum physical address used for virtual translation tables. */
-#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
-
-vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
-{
-	return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
-}
-
 /*
  * Address Guest Virtual to Host Virtual
  *
-- 
2.25.1

Re: [RFC 01/16] KVM: selftests: move vm_phy_pages_alloc() earlier in file

[Mingwei Zhang]

On Tue, Oct 5, 2021 at 4:46 PM Michael Roth <michael.roth@amd.com> wrote:
>
> Subsequent patches will break some of this code out into file-local
> helper functions, which will be used by functions like vm_vaddr_alloc(),
> which currently are defined earlier in the file, so a forward
> declaration would be needed.
>
> Instead, move it earlier in the file, just above vm_vaddr_alloc() and
> and friends, which are the main users.
>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>  tools/testing/selftests/kvm/lib/kvm_util.c | 146 ++++++++++-----------
>  1 file changed, 73 insertions(+), 73 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index 10a8ed691c66..92f59adddebe 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -1145,6 +1145,79 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
>         list_add(&vcpu->list, &vm->vcpus);
>  }
>
> +/*
> + * Physical Contiguous Page Allocator
> + *
> + * Input Args:
> + *   vm - Virtual Machine
> + *   num - number of pages
> + *   paddr_min - Physical address minimum
> + *   memslot - Memory region to allocate page from
> + *
> + * Output Args: None
> + *
> + * Return:
> + *   Starting physical address
> + *
> + * Within the VM specified by vm, locates a range of available physical
> + * pages at or above paddr_min. If found, the pages are marked as in use
> + * and their base address is returned. A TEST_ASSERT failure occurs if
> + * not enough pages are available at or above paddr_min.
> + */
> +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> +                             vm_paddr_t paddr_min, uint32_t memslot)
> +{
> +       struct userspace_mem_region *region;
> +       sparsebit_idx_t pg, base;
> +
> +       TEST_ASSERT(num > 0, "Must allocate at least one page");
> +
> +       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> +               "not divisible by page size.\n"
> +               "  paddr_min: 0x%lx page_size: 0x%x",
> +               paddr_min, vm->page_size);
> +
> +       region = memslot2region(vm, memslot);
> +       base = pg = paddr_min >> vm->page_shift;
> +
> +       do {
> +               for (; pg < base + num; ++pg) {
> +                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> +                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> +                               break;
> +                       }
> +               }
> +       } while (pg && pg != base + num);
> +
> +       if (pg == 0) {
> +               fprintf(stderr, "No guest physical page available, "
> +                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> +                       paddr_min, vm->page_size, memslot);
> +               fputs("---- vm dump ----\n", stderr);
> +               vm_dump(stderr, vm, 2);
> +               abort();
> +       }
> +
> +       for (pg = base; pg < base + num; ++pg)
> +               sparsebit_clear(region->unused_phy_pages, pg);
> +
> +       return base * vm->page_size;
> +}
> +
> +vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> +                            uint32_t memslot)
> +{
> +       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> +}
> +
> +/* Arbitrary minimum physical address used for virtual translation tables. */
> +#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> +
> +vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> +{
> +       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> +}
> +
>  /*
>   * VM Virtual Address Unused Gap
>   *
> @@ -2149,79 +2222,6 @@ const char *exit_reason_str(unsigned int exit_reason)
>         return "Unknown";
>  }
>
> -/*
> - * Physical Contiguous Page Allocator
> - *
> - * Input Args:
> - *   vm - Virtual Machine
> - *   num - number of pages
> - *   paddr_min - Physical address minimum
> - *   memslot - Memory region to allocate page from
> - *
> - * Output Args: None
> - *
> - * Return:
> - *   Starting physical address
> - *
> - * Within the VM specified by vm, locates a range of available physical
> - * pages at or above paddr_min. If found, the pages are marked as in use
> - * and their base address is returned. A TEST_ASSERT failure occurs if
> - * not enough pages are available at or above paddr_min.
> - */
> -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> -                             vm_paddr_t paddr_min, uint32_t memslot)
> -{
> -       struct userspace_mem_region *region;
> -       sparsebit_idx_t pg, base;
> -
> -       TEST_ASSERT(num > 0, "Must allocate at least one page");
> -
> -       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> -               "not divisible by page size.\n"
> -               "  paddr_min: 0x%lx page_size: 0x%x",
> -               paddr_min, vm->page_size);
> -
> -       region = memslot2region(vm, memslot);
> -       base = pg = paddr_min >> vm->page_shift;
> -
> -       do {
> -               for (; pg < base + num; ++pg) {
> -                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> -                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> -                               break;
> -                       }
> -               }
> -       } while (pg && pg != base + num);
> -
> -       if (pg == 0) {
> -               fprintf(stderr, "No guest physical page available, "
> -                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> -                       paddr_min, vm->page_size, memslot);
> -               fputs("---- vm dump ----\n", stderr);
> -               vm_dump(stderr, vm, 2);
> -               abort();
> -       }
> -
> -       for (pg = base; pg < base + num; ++pg)
> -               sparsebit_clear(region->unused_phy_pages, pg);
> -
> -       return base * vm->page_size;
> -}
> -
> -vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> -                            uint32_t memslot)
> -{
> -       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> -}
> -
> -/* Arbitrary minimum physical address used for virtual translation tables. */
> -#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> -
> -vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> -{
> -       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> -}
> -
>  /*
>   * Address Guest Virtual to Host Virtual
>   *
> --
> 2.25.1
>

Why move the function implementation? Maybe just adding a declaration
at the top of kvm_util.c should suffice.

Re: [RFC 01/16] KVM: selftests: move vm_phy_pages_alloc() earlier in file

[Michael Roth]

On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
> On Tue, Oct 5, 2021 at 4:46 PM Michael Roth <michael.roth@amd.com> wrote:
> >
> > Subsequent patches will break some of this code out into file-local
> > helper functions, which will be used by functions like vm_vaddr_alloc(),
> > which currently are defined earlier in the file, so a forward
> > declaration would be needed.
> >
> > Instead, move it earlier in the file, just above vm_vaddr_alloc() and
> > and friends, which are the main users.
> >
> > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > ---
> >  tools/testing/selftests/kvm/lib/kvm_util.c | 146 ++++++++++-----------
> >  1 file changed, 73 insertions(+), 73 deletions(-)
> >
> > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> > index 10a8ed691c66..92f59adddebe 100644
> > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > @@ -1145,6 +1145,79 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
> >         list_add(&vcpu->list, &vm->vcpus);
> >  }
> >
> > +/*
> > + * Physical Contiguous Page Allocator
> > + *
> > + * Input Args:
> > + *   vm - Virtual Machine
> > + *   num - number of pages
> > + *   paddr_min - Physical address minimum
> > + *   memslot - Memory region to allocate page from
> > + *
> > + * Output Args: None
> > + *
> > + * Return:
> > + *   Starting physical address
> > + *
> > + * Within the VM specified by vm, locates a range of available physical
> > + * pages at or above paddr_min. If found, the pages are marked as in use
> > + * and their base address is returned. A TEST_ASSERT failure occurs if
> > + * not enough pages are available at or above paddr_min.
> > + */
> > +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > +                             vm_paddr_t paddr_min, uint32_t memslot)
> > +{
> > +       struct userspace_mem_region *region;
> > +       sparsebit_idx_t pg, base;
> > +
> > +       TEST_ASSERT(num > 0, "Must allocate at least one page");
> > +
> > +       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> > +               "not divisible by page size.\n"
> > +               "  paddr_min: 0x%lx page_size: 0x%x",
> > +               paddr_min, vm->page_size);
> > +
> > +       region = memslot2region(vm, memslot);
> > +       base = pg = paddr_min >> vm->page_shift;
> > +
> > +       do {
> > +               for (; pg < base + num; ++pg) {
> > +                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> > +                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> > +                               break;
> > +                       }
> > +               }
> > +       } while (pg && pg != base + num);
> > +
> > +       if (pg == 0) {
> > +               fprintf(stderr, "No guest physical page available, "
> > +                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> > +                       paddr_min, vm->page_size, memslot);
> > +               fputs("---- vm dump ----\n", stderr);
> > +               vm_dump(stderr, vm, 2);
> > +               abort();
> > +       }
> > +
> > +       for (pg = base; pg < base + num; ++pg)
> > +               sparsebit_clear(region->unused_phy_pages, pg);
> > +
> > +       return base * vm->page_size;
> > +}
> > +
> > +vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > +                            uint32_t memslot)
> > +{
> > +       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> > +}
> > +
> > +/* Arbitrary minimum physical address used for virtual translation tables. */
> > +#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> > +
> > +vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> > +{
> > +       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> > +}
> > +
> >  /*
> >   * VM Virtual Address Unused Gap
> >   *
> > @@ -2149,79 +2222,6 @@ const char *exit_reason_str(unsigned int exit_reason)
> >         return "Unknown";
> >  }
> >
> > -/*
> > - * Physical Contiguous Page Allocator
> > - *
> > - * Input Args:
> > - *   vm - Virtual Machine
> > - *   num - number of pages
> > - *   paddr_min - Physical address minimum
> > - *   memslot - Memory region to allocate page from
> > - *
> > - * Output Args: None
> > - *
> > - * Return:
> > - *   Starting physical address
> > - *
> > - * Within the VM specified by vm, locates a range of available physical
> > - * pages at or above paddr_min. If found, the pages are marked as in use
> > - * and their base address is returned. A TEST_ASSERT failure occurs if
> > - * not enough pages are available at or above paddr_min.
> > - */
> > -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > -                             vm_paddr_t paddr_min, uint32_t memslot)
> > -{
> > -       struct userspace_mem_region *region;
> > -       sparsebit_idx_t pg, base;
> > -
> > -       TEST_ASSERT(num > 0, "Must allocate at least one page");
> > -
> > -       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> > -               "not divisible by page size.\n"
> > -               "  paddr_min: 0x%lx page_size: 0x%x",
> > -               paddr_min, vm->page_size);
> > -
> > -       region = memslot2region(vm, memslot);
> > -       base = pg = paddr_min >> vm->page_shift;
> > -
> > -       do {
> > -               for (; pg < base + num; ++pg) {
> > -                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> > -                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> > -                               break;
> > -                       }
> > -               }
> > -       } while (pg && pg != base + num);
> > -
> > -       if (pg == 0) {
> > -               fprintf(stderr, "No guest physical page available, "
> > -                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> > -                       paddr_min, vm->page_size, memslot);
> > -               fputs("---- vm dump ----\n", stderr);
> > -               vm_dump(stderr, vm, 2);
> > -               abort();
> > -       }
> > -
> > -       for (pg = base; pg < base + num; ++pg)
> > -               sparsebit_clear(region->unused_phy_pages, pg);
> > -
> > -       return base * vm->page_size;
> > -}
> > -
> > -vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > -                            uint32_t memslot)
> > -{
> > -       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> > -}
> > -
> > -/* Arbitrary minimum physical address used for virtual translation tables. */
> > -#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> > -
> > -vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> > -{
> > -       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> > -}
> > -
> >  /*
> >   * Address Guest Virtual to Host Virtual
> >   *
> > --
> > 2.25.1
> >
> 
> Why move the function implementation? Maybe just adding a declaration
> at the top of kvm_util.c should suffice.

At least from working on other projects I'd gotten the impression that
forward function declarations should be avoided if they can be solved by
moving the function above the caller. Certainly don't mind taking your
suggestion and dropping this patch if that's not the case here though.

Re: [RFC 01/16] KVM: selftests: move vm_phy_pages_alloc() earlier in file

[Paolo Bonzini]

On 21/10/21 05:45, Michael Roth wrote:
>> Why move the function implementation? Maybe just adding a declaration
>> at the top of kvm_util.c should suffice.
> At least from working on other projects I'd gotten the impression that
> forward function declarations should be avoided if they can be solved by
> moving the function above the caller. Certainly don't mind taking your
> suggestion and dropping this patch if that's not the case here though.

I don't mind moving the code, so the patch is fine.

Paolo

Re: [RFC 01/16] KVM: selftests: move vm_phy_pages_alloc() earlier in file

[Mingwei Zhang]

On Wed, Oct 20, 2021 at 8:47 PM Michael Roth <michael.roth@amd.com> wrote:
>
> On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
> > On Tue, Oct 5, 2021 at 4:46 PM Michael Roth <michael.roth@amd.com> wrote:
> > >
> > > Subsequent patches will break some of this code out into file-local
> > > helper functions, which will be used by functions like vm_vaddr_alloc(),
> > > which currently are defined earlier in the file, so a forward
> > > declaration would be needed.
> > >
> > > Instead, move it earlier in the file, just above vm_vaddr_alloc() and
> > > and friends, which are the main users.
> > >
> > > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > > ---
> > >  tools/testing/selftests/kvm/lib/kvm_util.c | 146 ++++++++++-----------
> > >  1 file changed, 73 insertions(+), 73 deletions(-)
> > >
> > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> > > index 10a8ed691c66..92f59adddebe 100644
> > > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > > @@ -1145,6 +1145,79 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
> > >         list_add(&vcpu->list, &vm->vcpus);
> > >  }
> > >
> > > +/*
> > > + * Physical Contiguous Page Allocator
> > > + *
> > > + * Input Args:
> > > + *   vm - Virtual Machine
> > > + *   num - number of pages
> > > + *   paddr_min - Physical address minimum
> > > + *   memslot - Memory region to allocate page from
> > > + *
> > > + * Output Args: None
> > > + *
> > > + * Return:
> > > + *   Starting physical address
> > > + *
> > > + * Within the VM specified by vm, locates a range of available physical
> > > + * pages at or above paddr_min. If found, the pages are marked as in use
> > > + * and their base address is returned. A TEST_ASSERT failure occurs if
> > > + * not enough pages are available at or above paddr_min.
> > > + */
> > > +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > > +                             vm_paddr_t paddr_min, uint32_t memslot)
> > > +{
> > > +       struct userspace_mem_region *region;
> > > +       sparsebit_idx_t pg, base;
> > > +
> > > +       TEST_ASSERT(num > 0, "Must allocate at least one page");
> > > +
> > > +       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> > > +               "not divisible by page size.\n"
> > > +               "  paddr_min: 0x%lx page_size: 0x%x",
> > > +               paddr_min, vm->page_size);
> > > +
> > > +       region = memslot2region(vm, memslot);
> > > +       base = pg = paddr_min >> vm->page_shift;
> > > +
> > > +       do {
> > > +               for (; pg < base + num; ++pg) {
> > > +                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> > > +                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> > > +                               break;
> > > +                       }
> > > +               }
> > > +       } while (pg && pg != base + num);
> > > +
> > > +       if (pg == 0) {
> > > +               fprintf(stderr, "No guest physical page available, "
> > > +                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> > > +                       paddr_min, vm->page_size, memslot);
> > > +               fputs("---- vm dump ----\n", stderr);
> > > +               vm_dump(stderr, vm, 2);
> > > +               abort();
> > > +       }
> > > +
> > > +       for (pg = base; pg < base + num; ++pg)
> > > +               sparsebit_clear(region->unused_phy_pages, pg);
> > > +
> > > +       return base * vm->page_size;
> > > +}
> > > +
> > > +vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > > +                            uint32_t memslot)
> > > +{
> > > +       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> > > +}
> > > +
> > > +/* Arbitrary minimum physical address used for virtual translation tables. */
> > > +#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> > > +
> > > +vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> > > +{
> > > +       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> > > +}
> > > +
> > >  /*
> > >   * VM Virtual Address Unused Gap
> > >   *
> > > @@ -2149,79 +2222,6 @@ const char *exit_reason_str(unsigned int exit_reason)
> > >         return "Unknown";
> > >  }
> > >
> > > -/*
> > > - * Physical Contiguous Page Allocator
> > > - *
> > > - * Input Args:
> > > - *   vm - Virtual Machine
> > > - *   num - number of pages
> > > - *   paddr_min - Physical address minimum
> > > - *   memslot - Memory region to allocate page from
> > > - *
> > > - * Output Args: None
> > > - *
> > > - * Return:
> > > - *   Starting physical address
> > > - *
> > > - * Within the VM specified by vm, locates a range of available physical
> > > - * pages at or above paddr_min. If found, the pages are marked as in use
> > > - * and their base address is returned. A TEST_ASSERT failure occurs if
> > > - * not enough pages are available at or above paddr_min.
> > > - */
> > > -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > > -                             vm_paddr_t paddr_min, uint32_t memslot)
> > > -{
> > > -       struct userspace_mem_region *region;
> > > -       sparsebit_idx_t pg, base;
> > > -
> > > -       TEST_ASSERT(num > 0, "Must allocate at least one page");
> > > -
> > > -       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> > > -               "not divisible by page size.\n"
> > > -               "  paddr_min: 0x%lx page_size: 0x%x",
> > > -               paddr_min, vm->page_size);
> > > -
> > > -       region = memslot2region(vm, memslot);
> > > -       base = pg = paddr_min >> vm->page_shift;
> > > -
> > > -       do {
> > > -               for (; pg < base + num; ++pg) {
> > > -                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> > > -                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> > > -                               break;
> > > -                       }
> > > -               }
> > > -       } while (pg && pg != base + num);
> > > -
> > > -       if (pg == 0) {
> > > -               fprintf(stderr, "No guest physical page available, "
> > > -                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> > > -                       paddr_min, vm->page_size, memslot);
> > > -               fputs("---- vm dump ----\n", stderr);
> > > -               vm_dump(stderr, vm, 2);
> > > -               abort();
> > > -       }
> > > -
> > > -       for (pg = base; pg < base + num; ++pg)
> > > -               sparsebit_clear(region->unused_phy_pages, pg);
> > > -
> > > -       return base * vm->page_size;
> > > -}
> > > -
> > > -vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > > -                            uint32_t memslot)
> > > -{
> > > -       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> > > -}
> > > -
> > > -/* Arbitrary minimum physical address used for virtual translation tables. */
> > > -#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> > > -
> > > -vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> > > -{
> > > -       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> > > -}
> > > -
> > >  /*
> > >   * Address Guest Virtual to Host Virtual
> > >   *
> > > --
> > > 2.25.1
> > >
> >
> > Why move the function implementation? Maybe just adding a declaration
> > at the top of kvm_util.c should suffice.
>
> At least from working on other projects I'd gotten the impression that
> forward function declarations should be avoided if they can be solved by
> moving the function above the caller. Certainly don't mind taking your
> suggestion and dropping this patch if that's not the case here though.

Understood. Yes, I think it would be better to follow your experience
then. I was thinking that if you move the code and then potentially
git blame on that function might point to you :)

Thanks.
-Mingwei

Re: [RFC 01/16] KVM: selftests: move vm_phy_pages_alloc() earlier in file

[Mingwei Zhang]

On Tue, Oct 26, 2021 at 8:52 AM Mingwei Zhang <mizhang@google.com> wrote:
>
> On Wed, Oct 20, 2021 at 8:47 PM Michael Roth <michael.roth@amd.com> wrote:
> >
> > On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
> > > On Tue, Oct 5, 2021 at 4:46 PM Michael Roth <michael.roth@amd.com> wrote:
> > > >
> > > > Subsequent patches will break some of this code out into file-local
> > > > helper functions, which will be used by functions like vm_vaddr_alloc(),
> > > > which currently are defined earlier in the file, so a forward
> > > > declaration would be needed.
> > > >
> > > > Instead, move it earlier in the file, just above vm_vaddr_alloc() and
> > > > and friends, which are the main users.
> > > >
> > > > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > > > ---
> > > >  tools/testing/selftests/kvm/lib/kvm_util.c | 146 ++++++++++-----------
> > > >  1 file changed, 73 insertions(+), 73 deletions(-)
> > > >
> > > > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> > > > index 10a8ed691c66..92f59adddebe 100644
> > > > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > > > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > > > @@ -1145,6 +1145,79 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
> > > >         list_add(&vcpu->list, &vm->vcpus);
> > > >  }
> > > >
> > > > +/*
> > > > + * Physical Contiguous Page Allocator
> > > > + *
> > > > + * Input Args:
> > > > + *   vm - Virtual Machine
> > > > + *   num - number of pages
> > > > + *   paddr_min - Physical address minimum
> > > > + *   memslot - Memory region to allocate page from
> > > > + *
> > > > + * Output Args: None
> > > > + *
> > > > + * Return:
> > > > + *   Starting physical address
> > > > + *
> > > > + * Within the VM specified by vm, locates a range of available physical
> > > > + * pages at or above paddr_min. If found, the pages are marked as in use
> > > > + * and their base address is returned. A TEST_ASSERT failure occurs if
> > > > + * not enough pages are available at or above paddr_min.
> > > > + */
> > > > +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > > > +                             vm_paddr_t paddr_min, uint32_t memslot)
> > > > +{
> > > > +       struct userspace_mem_region *region;
> > > > +       sparsebit_idx_t pg, base;
> > > > +
> > > > +       TEST_ASSERT(num > 0, "Must allocate at least one page");
> > > > +
> > > > +       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> > > > +               "not divisible by page size.\n"
> > > > +               "  paddr_min: 0x%lx page_size: 0x%x",
> > > > +               paddr_min, vm->page_size);
> > > > +
> > > > +       region = memslot2region(vm, memslot);
> > > > +       base = pg = paddr_min >> vm->page_shift;
> > > > +
> > > > +       do {
> > > > +               for (; pg < base + num; ++pg) {
> > > > +                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> > > > +                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> > > > +                               break;
> > > > +                       }
> > > > +               }
> > > > +       } while (pg && pg != base + num);
> > > > +
> > > > +       if (pg == 0) {
> > > > +               fprintf(stderr, "No guest physical page available, "
> > > > +                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> > > > +                       paddr_min, vm->page_size, memslot);
> > > > +               fputs("---- vm dump ----\n", stderr);
> > > > +               vm_dump(stderr, vm, 2);
> > > > +               abort();
> > > > +       }
> > > > +
> > > > +       for (pg = base; pg < base + num; ++pg)
> > > > +               sparsebit_clear(region->unused_phy_pages, pg);
> > > > +
> > > > +       return base * vm->page_size;
> > > > +}
> > > > +
> > > > +vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > > > +                            uint32_t memslot)
> > > > +{
> > > > +       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> > > > +}
> > > > +
> > > > +/* Arbitrary minimum physical address used for virtual translation tables. */
> > > > +#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> > > > +
> > > > +vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> > > > +{
> > > > +       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> > > > +}
> > > > +
> > > >  /*
> > > >   * VM Virtual Address Unused Gap
> > > >   *
> > > > @@ -2149,79 +2222,6 @@ const char *exit_reason_str(unsigned int exit_reason)
> > > >         return "Unknown";
> > > >  }
> > > >
> > > > -/*
> > > > - * Physical Contiguous Page Allocator
> > > > - *
> > > > - * Input Args:
> > > > - *   vm - Virtual Machine
> > > > - *   num - number of pages
> > > > - *   paddr_min - Physical address minimum
> > > > - *   memslot - Memory region to allocate page from
> > > > - *
> > > > - * Output Args: None
> > > > - *
> > > > - * Return:
> > > > - *   Starting physical address
> > > > - *
> > > > - * Within the VM specified by vm, locates a range of available physical
> > > > - * pages at or above paddr_min. If found, the pages are marked as in use
> > > > - * and their base address is returned. A TEST_ASSERT failure occurs if
> > > > - * not enough pages are available at or above paddr_min.
> > > > - */
> > > > -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > > > -                             vm_paddr_t paddr_min, uint32_t memslot)
> > > > -{
> > > > -       struct userspace_mem_region *region;
> > > > -       sparsebit_idx_t pg, base;
> > > > -
> > > > -       TEST_ASSERT(num > 0, "Must allocate at least one page");
> > > > -
> > > > -       TEST_ASSERT((paddr_min % vm->page_size) == 0, "Min physical address "
> > > > -               "not divisible by page size.\n"
> > > > -               "  paddr_min: 0x%lx page_size: 0x%x",
> > > > -               paddr_min, vm->page_size);
> > > > -
> > > > -       region = memslot2region(vm, memslot);
> > > > -       base = pg = paddr_min >> vm->page_shift;
> > > > -
> > > > -       do {
> > > > -               for (; pg < base + num; ++pg) {
> > > > -                       if (!sparsebit_is_set(region->unused_phy_pages, pg)) {
> > > > -                               base = pg = sparsebit_next_set(region->unused_phy_pages, pg);
> > > > -                               break;
> > > > -                       }
> > > > -               }
> > > > -       } while (pg && pg != base + num);
> > > > -
> > > > -       if (pg == 0) {
> > > > -               fprintf(stderr, "No guest physical page available, "
> > > > -                       "paddr_min: 0x%lx page_size: 0x%x memslot: %u\n",
> > > > -                       paddr_min, vm->page_size, memslot);
> > > > -               fputs("---- vm dump ----\n", stderr);
> > > > -               vm_dump(stderr, vm, 2);
> > > > -               abort();
> > > > -       }
> > > > -
> > > > -       for (pg = base; pg < base + num; ++pg)
> > > > -               sparsebit_clear(region->unused_phy_pages, pg);
> > > > -
> > > > -       return base * vm->page_size;
> > > > -}
> > > > -
> > > > -vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > > > -                            uint32_t memslot)
> > > > -{
> > > > -       return vm_phy_pages_alloc(vm, 1, paddr_min, memslot);
> > > > -}
> > > > -
> > > > -/* Arbitrary minimum physical address used for virtual translation tables. */
> > > > -#define KVM_GUEST_PAGE_TABLE_MIN_PADDR 0x180000
> > > > -
> > > > -vm_paddr_t vm_alloc_page_table(struct kvm_vm *vm)
> > > > -{
> > > > -       return vm_phy_page_alloc(vm, KVM_GUEST_PAGE_TABLE_MIN_PADDR, 0);
> > > > -}
> > > > -
> > > >  /*
> > > >   * Address Guest Virtual to Host Virtual
> > > >   *
> > > > --
> > > > 2.25.1
> > > >
> > >
> > > Why move the function implementation? Maybe just adding a declaration
> > > at the top of kvm_util.c should suffice.
> >
> > At least from working on other projects I'd gotten the impression that
> > forward function declarations should be avoided if they can be solved by
> > moving the function above the caller. Certainly don't mind taking your
> > suggestion and dropping this patch if that's not the case here though.
>
> Understood. Yes, I think it would be better to follow your experience
> then. I was thinking that if you move the code and then potentially
> git blame on that function might point to you :)
>
> Thanks.
> -Mingwei


Reviewed-by: Mingwei Zhang <mizhang@google.com>

Thanks.
-Mingwei

[RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Michael Roth]

VM implementations that make use of encrypted memory need a way to
configure things like the encryption/shared bit position for page
table handling, the default encryption policy for internal allocations
made by the core library, and a way to fetch the list/bitmap of
encrypted pages to do the actual memory encryption. Add an interface to
configure these parameters. Also introduce a sparsebit map to track
allocations/mappings that should be treated as encrypted, and provide
a way for VM implementations to retrieve it to handle operations
related memory encryption.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../testing/selftests/kvm/include/kvm_util.h  |  6 ++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 63 +++++++++++++++++--
 .../selftests/kvm/lib/kvm_util_internal.h     | 10 +++
 3 files changed, 75 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 010b59b13917..f417de80596c 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -348,6 +348,12 @@ int vm_create_device(struct kvm_vm *vm, struct kvm_create_device *cd);
 
 void assert_on_unhandled_exception(struct kvm_vm *vm, uint32_t vcpuid);
 
+void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
+			      uint8_t enc_bit);
+struct sparsebit *vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot,
+					     vm_paddr_t *gpa_start,
+					     uint64_t *size);
+
 /* Common ucalls */
 enum {
 	UCALL_NONE,
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 92f59adddebe..c58f930dedd2 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -631,6 +631,7 @@ static void __vm_mem_region_delete(struct kvm_vm *vm,
 		    "rc: %i errno: %i", ret, errno);
 
 	sparsebit_free(&region->unused_phy_pages);
+	sparsebit_free(&region->encrypted_phy_pages);
 	ret = munmap(region->mmap_start, region->mmap_size);
 	TEST_ASSERT(ret == 0, "munmap failed, rc: %i errno: %i", ret, errno);
 
@@ -924,6 +925,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
 	}
 
 	region->unused_phy_pages = sparsebit_alloc();
+	region->encrypted_phy_pages = sparsebit_alloc();
 	sparsebit_set_num(region->unused_phy_pages,
 		guest_paddr >> vm->page_shift, npages);
 	region->region.slot = slot;
@@ -1153,6 +1155,7 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
  *   num - number of pages
  *   paddr_min - Physical address minimum
  *   memslot - Memory region to allocate page from
+ *   encrypt - Whether to treat the pages as encrypted
  *
  * Output Args: None
  *
@@ -1164,11 +1167,13 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
  * and their base address is returned. A TEST_ASSERT failure occurs if
  * not enough pages are available at or above paddr_min.
  */
-vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
-			      vm_paddr_t paddr_min, uint32_t memslot)
+static vm_paddr_t
+_vm_phy_pages_alloc(struct kvm_vm *vm, size_t num, vm_paddr_t paddr_min,
+		    uint32_t memslot, bool encrypt)
 {
 	struct userspace_mem_region *region;
 	sparsebit_idx_t pg, base;
+	vm_paddr_t gpa;
 
 	TEST_ASSERT(num > 0, "Must allocate at least one page");
 
@@ -1198,10 +1203,25 @@ vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
 		abort();
 	}
 
-	for (pg = base; pg < base + num; ++pg)
+	for (pg = base; pg < base + num; ++pg) {
 		sparsebit_clear(region->unused_phy_pages, pg);
+		if (encrypt)
+			sparsebit_set(region->encrypted_phy_pages, pg);
+	}
+
+	gpa = base * vm->page_size;
 
-	return base * vm->page_size;
+	if (encrypt && vm->memcrypt.has_enc_bit)
+		gpa |= (1ULL << vm->memcrypt.enc_bit);
+
+	return gpa;
+}
+
+vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
+			      vm_paddr_t paddr_min, uint32_t memslot)
+{
+	return _vm_phy_pages_alloc(vm, 1, paddr_min, memslot,
+				   vm->memcrypt.enc_by_default);
 }
 
 vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
@@ -2146,6 +2166,10 @@ void vm_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
 			region->host_mem);
 		fprintf(stream, "%*sunused_phy_pages: ", indent + 2, "");
 		sparsebit_dump(stream, region->unused_phy_pages, 0);
+		if (vm->memcrypt.enabled) {
+			fprintf(stream, "%*sencrypted_phy_pages: ", indent + 2, "");
+			sparsebit_dump(stream, region->encrypted_phy_pages, 0);
+		}
 	}
 	fprintf(stream, "%*sMapped Virtual Pages:\n", indent, "");
 	sparsebit_dump(stream, vm->vpages_mapped, indent + 2);
@@ -2343,3 +2367,34 @@ int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid)
 
 	return ioctl(vcpu->fd, KVM_GET_STATS_FD, NULL);
 }
+
+void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
+			      uint8_t enc_bit)
+{
+	vm->memcrypt.enabled = true;
+	vm->memcrypt.enc_by_default = enc_by_default;
+	vm->memcrypt.has_enc_bit = has_enc_bit;
+	vm->memcrypt.enc_bit = enc_bit;
+}
+
+struct sparsebit *
+vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
+			   uint64_t *size)
+{
+	struct userspace_mem_region *region;
+	struct sparsebit *encrypted_phy_pages;
+
+	if (!vm->memcrypt.enabled)
+		return NULL;
+
+	region = memslot2region(vm, slot);
+	if (!region)
+		return NULL;
+
+	encrypted_phy_pages = sparsebit_alloc();
+	sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);
+	*size = region->region.memory_size;
+	*gpa_start = region->region.guest_phys_addr;
+
+	return encrypted_phy_pages;
+}
diff --git a/tools/testing/selftests/kvm/lib/kvm_util_internal.h b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
index a03febc24ba6..99ccab86115c 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util_internal.h
+++ b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
@@ -16,6 +16,7 @@
 struct userspace_mem_region {
 	struct kvm_userspace_memory_region region;
 	struct sparsebit *unused_phy_pages;
+	struct sparsebit *encrypted_phy_pages;
 	int fd;
 	off_t offset;
 	void *host_mem;
@@ -44,6 +45,14 @@ struct userspace_mem_regions {
 	DECLARE_HASHTABLE(slot_hash, 9);
 };
 
+/* Memory encryption policy/configuration. */
+struct vm_memcrypt {
+	bool enabled;
+	int8_t enc_by_default;
+	bool has_enc_bit;
+	int8_t enc_bit;
+};
+
 struct kvm_vm {
 	int mode;
 	unsigned long type;
@@ -67,6 +76,7 @@ struct kvm_vm {
 	vm_vaddr_t idt;
 	vm_vaddr_t handlers;
 	uint32_t dirty_ring_size;
+	struct vm_memcrypt memcrypt;
 };
 
 struct vcpu *vcpu_find(struct kvm_vm *vm, uint32_t vcpuid);
-- 
2.25.1

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Krish Sadhukhan]

On 10/5/21 4:44 PM, Michael Roth wrote:
> VM implementations that make use of encrypted memory need a way to
> configure things like the encryption/shared bit position for page
> table handling, the default encryption policy for internal allocations
> made by the core library, and a way to fetch the list/bitmap of
> encrypted pages to do the actual memory encryption. Add an interface to
> configure these parameters. Also introduce a sparsebit map to track
> allocations/mappings that should be treated as encrypted, and provide
> a way for VM implementations to retrieve it to handle operations
> related memory encryption.
>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>   .../testing/selftests/kvm/include/kvm_util.h  |  6 ++
>   tools/testing/selftests/kvm/lib/kvm_util.c    | 63 +++++++++++++++++--
>   .../selftests/kvm/lib/kvm_util_internal.h     | 10 +++
>   3 files changed, 75 insertions(+), 4 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> index 010b59b13917..f417de80596c 100644
> --- a/tools/testing/selftests/kvm/include/kvm_util.h
> +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> @@ -348,6 +348,12 @@ int vm_create_device(struct kvm_vm *vm, struct kvm_create_device *cd);
>   
>   void assert_on_unhandled_exception(struct kvm_vm *vm, uint32_t vcpuid);
>   
> +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> +			      uint8_t enc_bit);
> +struct sparsebit *vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot,
> +					     vm_paddr_t *gpa_start,
> +					     uint64_t *size);
> +
>   /* Common ucalls */
>   enum {
>   	UCALL_NONE,
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index 92f59adddebe..c58f930dedd2 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -631,6 +631,7 @@ static void __vm_mem_region_delete(struct kvm_vm *vm,
>   		    "rc: %i errno: %i", ret, errno);
>   
>   	sparsebit_free(&region->unused_phy_pages);
> +	sparsebit_free(&region->encrypted_phy_pages);
>   	ret = munmap(region->mmap_start, region->mmap_size);
>   	TEST_ASSERT(ret == 0, "munmap failed, rc: %i errno: %i", ret, errno);
>   
> @@ -924,6 +925,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
>   	}
>   
>   	region->unused_phy_pages = sparsebit_alloc();
> +	region->encrypted_phy_pages = sparsebit_alloc();
>   	sparsebit_set_num(region->unused_phy_pages,
>   		guest_paddr >> vm->page_shift, npages);
>   	region->region.slot = slot;
> @@ -1153,6 +1155,7 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
>    *   num - number of pages
>    *   paddr_min - Physical address minimum
>    *   memslot - Memory region to allocate page from
> + *   encrypt - Whether to treat the pages as encrypted
>    *
>    * Output Args: None
>    *
> @@ -1164,11 +1167,13 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
>    * and their base address is returned. A TEST_ASSERT failure occurs if
>    * not enough pages are available at or above paddr_min.
>    */
> -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> -			      vm_paddr_t paddr_min, uint32_t memslot)
> +static vm_paddr_t
> +_vm_phy_pages_alloc(struct kvm_vm *vm, size_t num, vm_paddr_t paddr_min,
> +		    uint32_t memslot, bool encrypt)
>   {
>   	struct userspace_mem_region *region;
>   	sparsebit_idx_t pg, base;
> +	vm_paddr_t gpa;
>   
>   	TEST_ASSERT(num > 0, "Must allocate at least one page");
>   
> @@ -1198,10 +1203,25 @@ vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
>   		abort();
>   	}
>   
> -	for (pg = base; pg < base + num; ++pg)
> +	for (pg = base; pg < base + num; ++pg) {
>   		sparsebit_clear(region->unused_phy_pages, pg);
> +		if (encrypt)
> +			sparsebit_set(region->encrypted_phy_pages, pg);
> +	}
> +
> +	gpa = base * vm->page_size;
>   
> -	return base * vm->page_size;
> +	if (encrypt && vm->memcrypt.has_enc_bit)
> +		gpa |= (1ULL << vm->memcrypt.enc_bit);
> +
> +	return gpa;
> +}
> +
> +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> +			      vm_paddr_t paddr_min, uint32_t memslot)
> +{
> +	return _vm_phy_pages_alloc(vm, 1, paddr_min, memslot,
> +				   vm->memcrypt.enc_by_default);
>   }
>   
>   vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> @@ -2146,6 +2166,10 @@ void vm_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
>   			region->host_mem);
>   		fprintf(stream, "%*sunused_phy_pages: ", indent + 2, "");
>   		sparsebit_dump(stream, region->unused_phy_pages, 0);
> +		if (vm->memcrypt.enabled) {
> +			fprintf(stream, "%*sencrypted_phy_pages: ", indent + 2, "");
> +			sparsebit_dump(stream, region->encrypted_phy_pages, 0);
> +		}
>   	}
>   	fprintf(stream, "%*sMapped Virtual Pages:\n", indent, "");
>   	sparsebit_dump(stream, vm->vpages_mapped, indent + 2);
> @@ -2343,3 +2367,34 @@ int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid)
>   
>   	return ioctl(vcpu->fd, KVM_GET_STATS_FD, NULL);
>   }
> +
> +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> +			      uint8_t enc_bit)
> +{
> +	vm->memcrypt.enabled = true;
> +	vm->memcrypt.enc_by_default = enc_by_default;
> +	vm->memcrypt.has_enc_bit = has_enc_bit;
> +	vm->memcrypt.enc_bit = enc_bit;
> +}
> +
> +struct sparsebit *
> +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
> +			   uint64_t *size)
> +{
> +	struct userspace_mem_region *region;
> +	struct sparsebit *encrypted_phy_pages;
> +
> +	if (!vm->memcrypt.enabled)
> +		return NULL;
> +
> +	region = memslot2region(vm, slot);
> +	if (!region)
> +		return NULL;
> +
> +	encrypted_phy_pages = sparsebit_alloc();
> +	sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);
> +	*size = region->region.memory_size;
> +	*gpa_start = region->region.guest_phys_addr;
> +
> +	return encrypted_phy_pages;
> +}
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util_internal.h b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
> index a03febc24ba6..99ccab86115c 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util_internal.h
> +++ b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
> @@ -16,6 +16,7 @@
>   struct userspace_mem_region {
>   	struct kvm_userspace_memory_region region;
>   	struct sparsebit *unused_phy_pages;
> +	struct sparsebit *encrypted_phy_pages;
>   	int fd;
>   	off_t offset;
>   	void *host_mem;
> @@ -44,6 +45,14 @@ struct userspace_mem_regions {
>   	DECLARE_HASHTABLE(slot_hash, 9);
>   };
>   
> +/* Memory encryption policy/configuration. */
> +struct vm_memcrypt {
> +	bool enabled;
> +	int8_t enc_by_default;
> +	bool has_enc_bit;
> +	int8_t enc_bit;
> +};
> +
>   struct kvm_vm {
>   	int mode;
>   	unsigned long type;
> @@ -67,6 +76,7 @@ struct kvm_vm {
>   	vm_vaddr_t idt;
>   	vm_vaddr_t handlers;
>   	uint32_t dirty_ring_size;
> +	struct vm_memcrypt memcrypt;


For readability, it's probably better to adopt a standard naming 
convention for structures, members and  functions ?  For example,

         encrypted_phy_pages    ->     enc_phy_pages

         struct vm_memcrypt  {    ->    struct vm_mem_enc {

         struct vm_memcrypt memcrypt    ->    struct vm_mem_enc  mem_enc

         vm_get_encrypted_phy_pages()    -> vm_get_enc_phy_pages



>   };
>   
>   struct vcpu *vcpu_find(struct kvm_vm *vm, uint32_t vcpuid);

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Michael Roth]

On Tue, Oct 12, 2021 at 07:20:41PM -0700, Krish Sadhukhan wrote:
> 
> On 10/5/21 4:44 PM, Michael Roth wrote:
> > VM implementations that make use of encrypted memory need a way to
> > configure things like the encryption/shared bit position for page
> > table handling, the default encryption policy for internal allocations
> > made by the core library, and a way to fetch the list/bitmap of
> > encrypted pages to do the actual memory encryption. Add an interface to
> > configure these parameters. Also introduce a sparsebit map to track
> > allocations/mappings that should be treated as encrypted, and provide
> > a way for VM implementations to retrieve it to handle operations
> > related memory encryption.
> > 
> > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > ---
> >   .../testing/selftests/kvm/include/kvm_util.h  |  6 ++
> >   tools/testing/selftests/kvm/lib/kvm_util.c    | 63 +++++++++++++++++--
> >   .../selftests/kvm/lib/kvm_util_internal.h     | 10 +++
> >   3 files changed, 75 insertions(+), 4 deletions(-)
> > 
> > diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
> > index 010b59b13917..f417de80596c 100644
> > --- a/tools/testing/selftests/kvm/include/kvm_util.h
> > +++ b/tools/testing/selftests/kvm/include/kvm_util.h
> > @@ -348,6 +348,12 @@ int vm_create_device(struct kvm_vm *vm, struct kvm_create_device *cd);
> >   void assert_on_unhandled_exception(struct kvm_vm *vm, uint32_t vcpuid);
> > +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> > +			      uint8_t enc_bit);
> > +struct sparsebit *vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot,
> > +					     vm_paddr_t *gpa_start,
> > +					     uint64_t *size);
> > +
> >   /* Common ucalls */
> >   enum {
> >   	UCALL_NONE,
> > diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> > index 92f59adddebe..c58f930dedd2 100644
> > --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> > +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> > @@ -631,6 +631,7 @@ static void __vm_mem_region_delete(struct kvm_vm *vm,
> >   		    "rc: %i errno: %i", ret, errno);
> >   	sparsebit_free(&region->unused_phy_pages);
> > +	sparsebit_free(&region->encrypted_phy_pages);
> >   	ret = munmap(region->mmap_start, region->mmap_size);
> >   	TEST_ASSERT(ret == 0, "munmap failed, rc: %i errno: %i", ret, errno);
> > @@ -924,6 +925,7 @@ void vm_userspace_mem_region_add(struct kvm_vm *vm,
> >   	}
> >   	region->unused_phy_pages = sparsebit_alloc();
> > +	region->encrypted_phy_pages = sparsebit_alloc();
> >   	sparsebit_set_num(region->unused_phy_pages,
> >   		guest_paddr >> vm->page_shift, npages);
> >   	region->region.slot = slot;
> > @@ -1153,6 +1155,7 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
> >    *   num - number of pages
> >    *   paddr_min - Physical address minimum
> >    *   memslot - Memory region to allocate page from
> > + *   encrypt - Whether to treat the pages as encrypted
> >    *
> >    * Output Args: None
> >    *
> > @@ -1164,11 +1167,13 @@ void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid)
> >    * and their base address is returned. A TEST_ASSERT failure occurs if
> >    * not enough pages are available at or above paddr_min.
> >    */
> > -vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > -			      vm_paddr_t paddr_min, uint32_t memslot)
> > +static vm_paddr_t
> > +_vm_phy_pages_alloc(struct kvm_vm *vm, size_t num, vm_paddr_t paddr_min,
> > +		    uint32_t memslot, bool encrypt)
> >   {
> >   	struct userspace_mem_region *region;
> >   	sparsebit_idx_t pg, base;
> > +	vm_paddr_t gpa;
> >   	TEST_ASSERT(num > 0, "Must allocate at least one page");
> > @@ -1198,10 +1203,25 @@ vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> >   		abort();
> >   	}
> > -	for (pg = base; pg < base + num; ++pg)
> > +	for (pg = base; pg < base + num; ++pg) {
> >   		sparsebit_clear(region->unused_phy_pages, pg);
> > +		if (encrypt)
> > +			sparsebit_set(region->encrypted_phy_pages, pg);
> > +	}
> > +
> > +	gpa = base * vm->page_size;
> > -	return base * vm->page_size;
> > +	if (encrypt && vm->memcrypt.has_enc_bit)
> > +		gpa |= (1ULL << vm->memcrypt.enc_bit);
> > +
> > +	return gpa;
> > +}
> > +
> > +vm_paddr_t vm_phy_pages_alloc(struct kvm_vm *vm, size_t num,
> > +			      vm_paddr_t paddr_min, uint32_t memslot)
> > +{
> > +	return _vm_phy_pages_alloc(vm, 1, paddr_min, memslot,
> > +				   vm->memcrypt.enc_by_default);
> >   }
> >   vm_paddr_t vm_phy_page_alloc(struct kvm_vm *vm, vm_paddr_t paddr_min,
> > @@ -2146,6 +2166,10 @@ void vm_dump(FILE *stream, struct kvm_vm *vm, uint8_t indent)
> >   			region->host_mem);
> >   		fprintf(stream, "%*sunused_phy_pages: ", indent + 2, "");
> >   		sparsebit_dump(stream, region->unused_phy_pages, 0);
> > +		if (vm->memcrypt.enabled) {
> > +			fprintf(stream, "%*sencrypted_phy_pages: ", indent + 2, "");
> > +			sparsebit_dump(stream, region->encrypted_phy_pages, 0);
> > +		}
> >   	}
> >   	fprintf(stream, "%*sMapped Virtual Pages:\n", indent, "");
> >   	sparsebit_dump(stream, vm->vpages_mapped, indent + 2);
> > @@ -2343,3 +2367,34 @@ int vcpu_get_stats_fd(struct kvm_vm *vm, uint32_t vcpuid)
> >   	return ioctl(vcpu->fd, KVM_GET_STATS_FD, NULL);
> >   }
> > +
> > +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> > +			      uint8_t enc_bit)
> > +{
> > +	vm->memcrypt.enabled = true;
> > +	vm->memcrypt.enc_by_default = enc_by_default;
> > +	vm->memcrypt.has_enc_bit = has_enc_bit;
> > +	vm->memcrypt.enc_bit = enc_bit;
> > +}
> > +
> > +struct sparsebit *
> > +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
> > +			   uint64_t *size)
> > +{
> > +	struct userspace_mem_region *region;
> > +	struct sparsebit *encrypted_phy_pages;
> > +
> > +	if (!vm->memcrypt.enabled)
> > +		return NULL;
> > +
> > +	region = memslot2region(vm, slot);
> > +	if (!region)
> > +		return NULL;
> > +
> > +	encrypted_phy_pages = sparsebit_alloc();
> > +	sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);
> > +	*size = region->region.memory_size;
> > +	*gpa_start = region->region.guest_phys_addr;
> > +
> > +	return encrypted_phy_pages;
> > +}
> > diff --git a/tools/testing/selftests/kvm/lib/kvm_util_internal.h b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
> > index a03febc24ba6..99ccab86115c 100644
> > --- a/tools/testing/selftests/kvm/lib/kvm_util_internal.h
> > +++ b/tools/testing/selftests/kvm/lib/kvm_util_internal.h
> > @@ -16,6 +16,7 @@
> >   struct userspace_mem_region {
> >   	struct kvm_userspace_memory_region region;
> >   	struct sparsebit *unused_phy_pages;
> > +	struct sparsebit *encrypted_phy_pages;
> >   	int fd;
> >   	off_t offset;
> >   	void *host_mem;
> > @@ -44,6 +45,14 @@ struct userspace_mem_regions {
> >   	DECLARE_HASHTABLE(slot_hash, 9);
> >   };
> > +/* Memory encryption policy/configuration. */
> > +struct vm_memcrypt {
> > +	bool enabled;
> > +	int8_t enc_by_default;
> > +	bool has_enc_bit;
> > +	int8_t enc_bit;
> > +};
> > +
> >   struct kvm_vm {
> >   	int mode;
> >   	unsigned long type;
> > @@ -67,6 +76,7 @@ struct kvm_vm {
> >   	vm_vaddr_t idt;
> >   	vm_vaddr_t handlers;
> >   	uint32_t dirty_ring_size;
> > +	struct vm_memcrypt memcrypt;
> 
> 
> For readability, it's probably better to adopt a standard naming convention
> for structures, members and  functions ?  For example,
> 
>         encrypted_phy_pages    ->     enc_phy_pages
> 
>         struct vm_memcrypt  {    ->    struct vm_mem_enc {
> 
>         struct vm_memcrypt memcrypt    ->    struct vm_mem_enc  mem_enc
> 
>         vm_get_encrypted_phy_pages()    -> vm_get_enc_phy_pages
> 
> 
> 

Makes sense, I will use this naming convention for the next spin.

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Paolo Bonzini]

On 13/10/21 17:07, Michael Roth wrote:
>>
>> For readability, it's probably better to adopt a standard naming convention
>> for structures, members and  functions ?  For example,
>>
>>          encrypted_phy_pages    ->     enc_phy_pages
>>
>>          struct vm_memcrypt  {    ->    struct vm_mem_enc {
>>
>>          struct vm_memcrypt memcrypt    ->    struct vm_mem_enc  mem_enc
>>
>>          vm_get_encrypted_phy_pages()    -> vm_get_enc_phy_pages
>>
>>
>>
> Makes sense, I will use this naming convention for the next spin.

And again I liked yours more. :)

Paolo

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Mingwei Zhang]

> +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> +                             uint8_t enc_bit)
> +{
> +       vm->memcrypt.enabled = true;
> +       vm->memcrypt.enc_by_default = enc_by_default;
> +       vm->memcrypt.has_enc_bit = has_enc_bit;
> +       vm->memcrypt.enc_bit = enc_bit;
> +}
> +
> +struct sparsebit *
> +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
> +                          uint64_t *size)
> +{
> +       struct userspace_mem_region *region;
> +       struct sparsebit *encrypted_phy_pages;
> +
> +       if (!vm->memcrypt.enabled)
> +               return NULL;
> +
> +       region = memslot2region(vm, slot);
> +       if (!region)
> +               return NULL;
> +
> +       encrypted_phy_pages = sparsebit_alloc();
> +       sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);

Do we have to make a copy for the sparsebit? Why not just return the
pointer? By looking at your subsequent patches, I find that this data
structure seems to be just read-only?

-Mingwei

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Michael Roth]

On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
> > +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> > +                             uint8_t enc_bit)
> > +{
> > +       vm->memcrypt.enabled = true;
> > +       vm->memcrypt.enc_by_default = enc_by_default;
> > +       vm->memcrypt.has_enc_bit = has_enc_bit;
> > +       vm->memcrypt.enc_bit = enc_bit;
> > +}
> > +
> > +struct sparsebit *
> > +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
> > +                          uint64_t *size)
> > +{
> > +       struct userspace_mem_region *region;
> > +       struct sparsebit *encrypted_phy_pages;
> > +
> > +       if (!vm->memcrypt.enabled)
> > +               return NULL;
> > +
> > +       region = memslot2region(vm, slot);
> > +       if (!region)
> > +               return NULL;
> > +
> > +       encrypted_phy_pages = sparsebit_alloc();
> > +       sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);
> 
> Do we have to make a copy for the sparsebit? Why not just return the
> pointer? By looking at your subsequent patches, I find that this data
> structure seems to be just read-only?

Yes, it's only intended to be used for read access. But I'll if I can
enforce that without the need to use a copy.

> 
> -Mingwei

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Paolo Bonzini]

On 21/10/21 05:37, Michael Roth wrote:
>> Do we have to make a copy for the sparsebit? Why not just return the
>> pointer? By looking at your subsequent patches, I find that this data
>> structure seems to be just read-only?
> Yes, it's only intended to be used for read access. But I'll if I can
> enforce that without the need to use a copy.
> 

Return it as a const pointer?

Paolo

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Mingwei Zhang]

On Wed, Oct 20, 2021 at 8:46 PM Michael Roth <michael.roth@amd.com> wrote:
>
> On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
> > > +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> > > +                             uint8_t enc_bit)
> > > +{
> > > +       vm->memcrypt.enabled = true;
> > > +       vm->memcrypt.enc_by_default = enc_by_default;
> > > +       vm->memcrypt.has_enc_bit = has_enc_bit;
> > > +       vm->memcrypt.enc_bit = enc_bit;
> > > +}
> > > +
> > > +struct sparsebit *
> > > +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
> > > +                          uint64_t *size)
> > > +{
> > > +       struct userspace_mem_region *region;
> > > +       struct sparsebit *encrypted_phy_pages;
> > > +
> > > +       if (!vm->memcrypt.enabled)
> > > +               return NULL;
> > > +
> > > +       region = memslot2region(vm, slot);
> > > +       if (!region)
> > > +               return NULL;
> > > +
> > > +       encrypted_phy_pages = sparsebit_alloc();
> > > +       sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);
> >
> > Do we have to make a copy for the sparsebit? Why not just return the
> > pointer? By looking at your subsequent patches, I find that this data
> > structure seems to be just read-only?
>
> Yes, it's only intended to be used for read access. But I'll if I can
> enforce that without the need to use a copy.
>

Understood. Thanks for the clarification. Yeah, I think both making a
copy and returning a const pointer should work. I will leave that to
you then.

Thanks.
-Mingwei

Re: [RFC 02/16] KVM: selftests: add hooks for managing encrypted guest memory

[Mingwei Zhang]

On Tue, Oct 26, 2021 at 8:48 AM Mingwei Zhang <mizhang@google.com> wrote:
>
> On Wed, Oct 20, 2021 at 8:46 PM Michael Roth <michael.roth@amd.com> wrote:
> >
> > On Mon, Oct 18, 2021 at 08:00:00AM -0700, Mingwei Zhang wrote:
> > > > +void vm_set_memory_encryption(struct kvm_vm *vm, bool enc_by_default, bool has_enc_bit,
> > > > +                             uint8_t enc_bit)
> > > > +{
> > > > +       vm->memcrypt.enabled = true;
> > > > +       vm->memcrypt.enc_by_default = enc_by_default;
> > > > +       vm->memcrypt.has_enc_bit = has_enc_bit;
> > > > +       vm->memcrypt.enc_bit = enc_bit;
> > > > +}
> > > > +
> > > > +struct sparsebit *
> > > > +vm_get_encrypted_phy_pages(struct kvm_vm *vm, int slot, vm_paddr_t *gpa_start,
> > > > +                          uint64_t *size)
> > > > +{
> > > > +       struct userspace_mem_region *region;
> > > > +       struct sparsebit *encrypted_phy_pages;
> > > > +
> > > > +       if (!vm->memcrypt.enabled)
> > > > +               return NULL;
> > > > +
> > > > +       region = memslot2region(vm, slot);
> > > > +       if (!region)
> > > > +               return NULL;
> > > > +
> > > > +       encrypted_phy_pages = sparsebit_alloc();
> > > > +       sparsebit_copy(encrypted_phy_pages, region->encrypted_phy_pages);
> > >
> > > Do we have to make a copy for the sparsebit? Why not just return the
> > > pointer? By looking at your subsequent patches, I find that this data
> > > structure seems to be just read-only?
> >
> > Yes, it's only intended to be used for read access. But I'll if I can
> > enforce that without the need to use a copy.
> >
>
> Understood. Thanks for the clarification. Yeah, I think both making a
> copy and returning a const pointer should work. I will leave that to
> you then.
>
> Thanks.
> -Mingwei

Reviewed-by: Mingwei Zhang <mizhang@google.com>

Thanks.
-Mingwei

[RFC 03/16] KVM: selftests: handle encryption bits in page tables

[Michael Roth]

SEV guests rely on an encyption bit which resides within the range that
current code treats as address bits. Guest code will expect these bits
to be set appropriately in their page tables, whereas helpers like
addr_gpa2hva() will expect these bits to be masked away prior to
translation. Add proper handling for these cases.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../testing/selftests/kvm/include/kvm_util.h  |  1 +
 tools/testing/selftests/kvm/lib/kvm_util.c    | 23 +++++++++++++++-
 .../selftests/kvm/lib/x86_64/processor.c      | 26 +++++++++----------
 3 files changed, 36 insertions(+), 14 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index f417de80596c..4bf686d664cc 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -152,6 +152,7 @@ void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa);
 void *addr_gva2hva(struct kvm_vm *vm, vm_vaddr_t gva);
 vm_paddr_t addr_hva2gpa(struct kvm_vm *vm, void *hva);
 void *addr_gpa2alias(struct kvm_vm *vm, vm_paddr_t gpa);
+vm_paddr_t addr_raw2gpa(struct kvm_vm *vm, vm_vaddr_t gpa_raw);
 
 /*
  * Address Guest Virtual to Guest Physical
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index c58f930dedd2..ef88fdc7e46b 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1443,6 +1443,26 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 	}
 }
 
+/*
+ * Mask off any special bits from raw GPA
+ *
+ * Input Args:
+ *   vm - Virtual Machine
+ *   gpa_raw - Raw VM physical address
+ *
+ * Output Args: None
+ *
+ * Return:
+ *   GPA with special bits (e.g. shared/encrypted) masked off.
+ */
+vm_paddr_t addr_raw2gpa(struct kvm_vm *vm, vm_paddr_t gpa_raw)
+{
+	if (!vm->memcrypt.has_enc_bit)
+		return gpa_raw;
+
+	return gpa_raw & ~(1ULL << vm->memcrypt.enc_bit);
+}
+
 /*
  * Address VM Physical to Host Virtual
  *
@@ -1460,9 +1480,10 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
  * address providing the memory to the vm physical address is returned.
  * A TEST_ASSERT failure occurs if no region containing gpa exists.
  */
-void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa)
+void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa_raw)
 {
 	struct userspace_mem_region *region;
+	vm_paddr_t gpa = addr_raw2gpa(vm, gpa_raw);
 
 	region = userspace_mem_region_find(vm, gpa, gpa);
 	if (!region) {
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 28cb881f440d..0bbd88fe1127 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -198,7 +198,7 @@ static void *virt_get_pte(struct kvm_vm *vm, uint64_t pt_pfn, uint64_t vaddr,
 static struct pageUpperEntry *virt_create_upper_pte(struct kvm_vm *vm,
 						    uint64_t pt_pfn,
 						    uint64_t vaddr,
-						    uint64_t paddr,
+						    uint64_t paddr_raw,
 						    int level,
 						    enum x86_page_size page_size)
 {
@@ -208,10 +208,9 @@ static struct pageUpperEntry *virt_create_upper_pte(struct kvm_vm *vm,
 		pte->writable = true;
 		pte->present = true;
 		pte->page_size = (level == page_size);
-		if (pte->page_size)
-			pte->pfn = paddr >> vm->page_shift;
-		else
-			pte->pfn = vm_alloc_page_table(vm) >> vm->page_shift;
+		if (!pte->page_size)
+			paddr_raw = vm_alloc_page_table(vm);
+		pte->pfn = paddr_raw >> vm->page_shift;
 	} else {
 		/*
 		 * Entry already present.  Assert that the caller doesn't want
@@ -228,12 +227,13 @@ static struct pageUpperEntry *virt_create_upper_pte(struct kvm_vm *vm,
 	return pte;
 }
 
-void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
+void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr_raw,
 		   enum x86_page_size page_size)
 {
 	const uint64_t pg_size = 1ull << ((page_size * 9) + 12);
 	struct pageUpperEntry *pml4e, *pdpe, *pde;
 	struct pageTableEntry *pte;
+	uint64_t paddr = addr_raw2gpa(vm, paddr_raw);
 
 	TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K,
 		    "Unknown or unsupported guest mode, mode: 0x%x", vm->mode);
@@ -256,15 +256,15 @@ void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 	 * early if a hugepage was created.
 	 */
 	pml4e = virt_create_upper_pte(vm, vm->pgd >> vm->page_shift,
-				      vaddr, paddr, 3, page_size);
+				      vaddr, paddr_raw, 3, page_size);
 	if (pml4e->page_size)
 		return;
 
-	pdpe = virt_create_upper_pte(vm, pml4e->pfn, vaddr, paddr, 2, page_size);
+	pdpe = virt_create_upper_pte(vm, pml4e->pfn, vaddr, paddr_raw, 2, page_size);
 	if (pdpe->page_size)
 		return;
 
-	pde = virt_create_upper_pte(vm, pdpe->pfn, vaddr, paddr, 1, page_size);
+	pde = virt_create_upper_pte(vm, pdpe->pfn, vaddr, paddr_raw, 1, page_size);
 	if (pde->page_size)
 		return;
 
@@ -272,14 +272,14 @@ void __virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 	pte = virt_get_pte(vm, pde->pfn, vaddr, 0);
 	TEST_ASSERT(!pte->present,
 		    "PTE already present for 4k page at vaddr: 0x%lx\n", vaddr);
-	pte->pfn = paddr >> vm->page_shift;
+	pte->pfn = paddr_raw >> vm->page_shift;
 	pte->writable = true;
 	pte->present = 1;
 }
 
-void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr)
+void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr_raw)
 {
-	__virt_pg_map(vm, vaddr, paddr, X86_PAGE_SIZE_4K);
+	__virt_pg_map(vm, vaddr, paddr_raw, X86_PAGE_SIZE_4K);
 }
 
 static struct pageTableEntry *_vm_get_page_table_entry(struct kvm_vm *vm, int vcpuid,
@@ -587,7 +587,7 @@ vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
 	if (!pte[index[0]].present)
 		goto unmapped_gva;
 
-	return (pte[index[0]].pfn * vm->page_size) + (gva & 0xfffu);
+	return addr_raw2gpa(vm, ((uint64_t)pte[index[0]].pfn * vm->page_size)) + (gva & 0xfffu);
 
 unmapped_gva:
 	TEST_FAIL("No mapping for vm virtual address, gva: 0x%lx", gva);
-- 
2.25.1

Re: [RFC 03/16] KVM: selftests: handle encryption bits in page tables

[Paolo Bonzini]

On 06/10/21 01:44, Michael Roth wrote:
> SEV guests rely on an encyption bit which resides within the range that
> current code treats as address bits. Guest code will expect these bits
> to be set appropriately in their page tables, whereas helpers like
> addr_gpa2hva() will expect these bits to be masked away prior to
> translation. Add proper handling for these cases.

This is not what you're doing below in addr_gpa2hva, though---or did I 
misunderstand?

I may be wrong due to not actually having written the code, but I'd 
prefer if most of these APIs worked only if the C bit has already been 
stripped.  In general it's quite unlikely for host code to deal with C=1 
pages, so it's worth pointing out explicitly the cases where it does.

Paolo

> @@ -1460,9 +1480,10 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
>    * address providing the memory to the vm physical address is returned.
>    * A TEST_ASSERT failure occurs if no region containing gpa exists.
>    */
> -void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa)
> +void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa_raw)
>   {
>   	struct userspace_mem_region *region;

Re: [RFC 03/16] KVM: selftests: handle encryption bits in page tables

[Michael Roth]

On Thu, Oct 21, 2021 at 05:26:26PM +0200, Paolo Bonzini wrote:
> On 06/10/21 01:44, Michael Roth wrote:
> > SEV guests rely on an encyption bit which resides within the range that
> > current code treats as address bits. Guest code will expect these bits
> > to be set appropriately in their page tables, whereas helpers like
> > addr_gpa2hva() will expect these bits to be masked away prior to
> > translation. Add proper handling for these cases.
> 
> This is not what you're doing below in addr_gpa2hva, though---or did I
> misunderstand?

The confusion is warranted, addr_gpa2hva() *doesn't* expect the C bit to
be masked in advance so the wording is pretty confusing.

I think I was referring the fact that internally it doesn't need/want the
C-bit, in this case it just masks it away as a convenience to callers,
as opposed to the other functions modified in the patch that actually
make use of it.

It's convenient because page table walkers/mappers make use of
addr_gpa2hva() to do things like silently mask away C-bits via when
translating PTEs to host addresses. We easily convert those callers from:

  addr_gpa2hva(paddr)

to this:

  addr_gpa2hva(addr_raw2gpa(paddr))

but now all new code needs to consider whether it might be dealing with
C-bits or not prior to deciding to pass it to addr_gpa2hva() (or not
really think about it, and add addr_gpa2raw() "just in case"). So since
it's always harmless to mask it away silently addr_gpa2hva(), the
logic/code seems to benefit a good deal if we indicate clearly that
addr_gpa2hva() can accept a 'raw' GPA, and will ignore it completely.

But not a big deal either way if you prefer to keep that explicit. And
commit message still needs to be clarified.

> 
> I may be wrong due to not actually having written the code, but I'd prefer
> if most of these APIs worked only if the C bit has already been stripped.
> In general it's quite unlikely for host code to deal with C=1 pages, so it's
> worth pointing out explicitly the cases where it does.

I've tried to indicate functions that expect the C-bit by adding the 'raw_'
prefix to the gpa/paddr parameters, but as you pointed out with
addr_gpa2hva() it's already a bit inconsistent in that regard, and there's
a couple cases like virt_map() where I should use the 'raw_' prefix as well
that I've missed here.

So that should be addressed, and maybe some additional comments/assertions
might be warranted to guard against cases where the C-bit is passed in
unexpectedly.

But I should probably re-assess why the C-bit is being passed around in
the first place:

 - vm_phy_page[s]_alloc() is the main 'source' for 'raw' GPAs with the
   C-bit set. it determines this based on vm_memcrypt encryption policy,
   and updates the encryption bitmask as well.
 - vm_phy_page[s]_alloc() is callable both in kvm_util lib as well as
   individual tests.
 - in theory, encoding the C-bit in the returned vm_paddr_t means that
   vm_phy_page[s]_alloc() callers can pass that directly into
   virt_map/virt_pg_map() and this will "just work" for both
   encrypted/non-encrypted guests.
 - by masking it away in addr_gpa2hva(), existing tests/code flow mostly
   "just works" as well.

But taking a closer look, in cases where vm_phy_page[s]_alloc() is called
directly by tests, like set_memory_region_test, emulator_error_test, and
smm_test, that raw GPA is compared to hardcoded non-raw GPAs, so they'd
still end up needing fixups to work with the proposed transparent-SEV-mode
stuff. And future code would need to be written to account for this, so
it doesn't really "just work" after all..

So it's worth considering the alternative approach of *not* encoding the
C-bit into GPAs returned by vm_phy_page[s]_alloc(). That would likely
involve introducing something like addr_gpa2raw(), which adds in the
C-bit according to the encryption bitmap as-needed. If we do that:

  - virt_map()/virt_pg_map() still need to accept 'raw' GPAs, since they
    need to deal with cases where pages are being mapping that weren't
    allocated by vm_phy_page[s]_alloc(), and so aren't recorded in the
    bitmap. in those cases it is up to test code to provide the C-bit
    when needed (e.g. things like separate linear mappings for pa()-like
    stuff in guest code).

  - for cases where vm_phy_page[s]_alloc() determines whether the page
    is encrypted, addr_gpa2raw() needs to be used to add back the C-bit
    prior to passing it to virt_map()/virt_pg_map(), both in the library and
    the test code. vm_vaddr_* allocations would handle all this under the
    covers as they do now.

So test code would need to consider cases where addr_gpa2raw() needs to be
used to set the C-bit (which is basically only when they want to mix usage
of the vm_phy_page[s]_alloc with their own mapping of the guest page tables,
which doesn't seem to be done in any existing tests anyway).

The library code would need these addr_gpa2raw() hooks in places where
it calls virt_*map() internally. Probably just a handful of places
though.

Assuming there's no issues with this alternative approach that I may be
missing, I'll look at doing it this way for the next spin.

Even in this alternative approach though, having addr_gpa2hva() silently
mask away C-bit still seems useful for the reasons above, but again, no
strong feelings one way or the other on that.

> 
> Paolo
> 
> > @@ -1460,9 +1480,10 @@ void virt_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
> >    * address providing the memory to the vm physical address is returned.
> >    * A TEST_ASSERT failure occurs if no region containing gpa exists.
> >    */
> > -void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa)
> > +void *addr_gpa2hva(struct kvm_vm *vm, vm_paddr_t gpa_raw)
> >   {
> >   	struct userspace_mem_region *region;
> 

Re: [RFC 03/16] KVM: selftests: handle encryption bits in page tables

[Paolo Bonzini]

On 24/10/21 18:49, Michael Roth wrote:
> So test code would need to consider cases where addr_gpa2raw() needs to be
> used to set the C-bit (which is basically only when they want to mix usage
> of the vm_phy_page[s]_alloc with their own mapping of the guest page tables,
> which doesn't seem to be done in any existing tests anyway).

Yes, and it seems like a more rare case in general.

> The library code would need these addr_gpa2raw() hooks in places where
> it calls virt_*map() internally. Probably just a handful of places
> though.

Either that, or you can have virt_*map that consults the encryption 
bitmap, and virt_*map_enc (or _raw, doesn't matter) that takes the 
encryption state explicitly as a bool.

> Even in this alternative approach though, having addr_gpa2hva() silently
> mask away C-bit still seems useful for the reasons above, but again, no
> strong feelings one way or the other on that.

Ok, keep it the way you find more useful.

Paolo

Re: [RFC 03/16] KVM: selftests: handle encryption bits in page tables

[Michael Roth]

On Mon, Oct 25, 2021 at 09:34:10AM +0200, Paolo Bonzini wrote:
> On 24/10/21 18:49, Michael Roth wrote:
> > So test code would need to consider cases where addr_gpa2raw() needs to be
> > used to set the C-bit (which is basically only when they want to mix usage
> > of the vm_phy_page[s]_alloc with their own mapping of the guest page tables,
> > which doesn't seem to be done in any existing tests anyway).
> 
> Yes, and it seems like a more rare case in general.
> 
> > The library code would need these addr_gpa2raw() hooks in places where
> > it calls virt_*map() internally. Probably just a handful of places
> > though.
> 
> Either that, or you can have virt_*map that consults the encryption bitmap,
> and virt_*map_enc (or _raw, doesn't matter) that takes the encryption state
> explicitly as a bool.

That sounds promising. Will give that a shot. Thanks!

[RFC 09/16] KVM: selftests: account for error code in #VC exception frame

[Michael Roth]

Exception 29 (#VC) pushes an error_code parameter on the stack. Update
the exception list to reflect this.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/lib/x86_64/handlers.S | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/lib/x86_64/handlers.S b/tools/testing/selftests/kvm/lib/x86_64/handlers.S
index 7629819734af..19715a58f5d2 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/handlers.S
+++ b/tools/testing/selftests/kvm/lib/x86_64/handlers.S
@@ -76,6 +76,8 @@ idt_handler_code:
 	HANDLERS has_error=1 from=10 to=14
 	HANDLERS has_error=0 from=15 to=16
 	HANDLERS has_error=1 from=17 to=17
-	HANDLERS has_error=0 from=18 to=255
+	HANDLERS has_error=0 from=18 to=28
+	HANDLERS has_error=1 from=29 to=29
+	HANDLERS has_error=0 from=30 to=255
 
 .section        .note.GNU-stack, "", %progbits
-- 
2.25.1

[RFC 10/16] KVM: selftests: add support for creating SEV-ES guests

[Michael Roth]

Only a couple KVM_SEV_* ioctls need to be handled differently for
SEV-ES. Do so when the specified policy indicates SEV-ES support.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/lib/x86_64/sev.c | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
index adda3b396566..d01b0f637ced 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/sev.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
@@ -238,13 +238,17 @@ struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
 		return NULL;
 	sev->sev_policy = policy;
 
-	kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
+	if (sev->sev_policy & SEV_POLICY_ES)
+		kvm_sev_ioctl(sev, KVM_SEV_ES_INIT, NULL);
+	else
+		kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
 
 	vm_set_memory_encryption(vm, true, true, sev->enc_bit);
 	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
 	sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
 
-	pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
+	pr_info("%s guest created, policy: 0x%x, size: %lu KB\n",
+		(sev->sev_policy & SEV_POLICY_ES) ? "SEV-ES" : "SEV",
 		sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
 
 	return sev;
@@ -269,6 +273,9 @@ void sev_vm_launch(struct sev_vm *sev)
 		    "Unexpected guest state: %d", ksev_status.state);
 
 	sev_encrypt(sev);
+
+	if (sev->sev_policy & SEV_POLICY_ES)
+		kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_VMSA, NULL);
 }
 
 void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
-- 
2.25.1

[RFC 11/16] KVM: selftests: add library for handling SEV-ES-related exits

[Michael Roth]

Add (or copy from kernel) routines related to handling #VC exceptions
(only for cpuid currently) or issuing vmgexits. These will be used
mostly by guest code.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/Makefile          |   2 +-
 .../kvm/include/x86_64/sev_exitlib.h          |  14 +
 .../selftests/kvm/include/x86_64/svm.h        |  35 +++
 .../selftests/kvm/include/x86_64/svm_util.h   |   1 +
 .../selftests/kvm/lib/x86_64/sev_exitlib.c    | 249 ++++++++++++++++++
 5 files changed, 300 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index aa8901bdbd22..7b3261cc60a3 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -35,7 +35,7 @@ endif
 
 LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
 LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
-LIBKVM_x86_64 += lib/x86_64/sev.c
+LIBKVM_x86_64 += lib/x86_64/sev.c lib/x86_64/sev_exitlib.c
 LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
 LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
 
diff --git a/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h b/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
new file mode 100644
index 000000000000..4b67b4004dfa
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * VC/vmgexit/GHCB-related helpers for SEV-ES/SEV-SNP guests.
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+
+#ifndef SELFTEST_KVM_SEV_EXITLIB_H
+#define SELFTEST_KVM_SEV_EXITLIB_H
+
+int sev_es_handle_vc(void *ghcb, u64 ghcb_gpa, struct ex_regs *regs);
+void sev_es_terminate(int reason);
+
+#endif /* SELFTEST_KVM_SEV_EXITLIB_H */
diff --git a/tools/testing/selftests/kvm/include/x86_64/svm.h b/tools/testing/selftests/kvm/include/x86_64/svm.h
index f4ea2355dbc2..d633caea4b7d 100644
--- a/tools/testing/selftests/kvm/include/x86_64/svm.h
+++ b/tools/testing/selftests/kvm/include/x86_64/svm.h
@@ -204,6 +204,41 @@ struct __attribute__ ((__packed__)) vmcb_save_area {
 	u64 br_to;
 	u64 last_excp_from;
 	u64 last_excp_to;
+
+	/*
+	 * The following part of the save area is valid only for
+	 * SEV-ES guests when referenced through the GHCB or for
+	 * saving to the host save area.
+	 */
+	u8 reserved_7[80];
+	u32 pkru;
+	u8 reserved_7a[20];
+	u64 reserved_8;		/* rax already available at 0x01f8 */
+	u64 rcx;
+	u64 rdx;
+	u64 rbx;
+	u64 reserved_9;		/* rsp already available at 0x01d8 */
+	u64 rbp;
+	u64 rsi;
+	u64 rdi;
+	u64 r8;
+	u64 r9;
+	u64 r10;
+	u64 r11;
+	u64 r12;
+	u64 r13;
+	u64 r14;
+	u64 r15;
+	u8 reserved_10[16];
+	u64 sw_exit_code;
+	u64 sw_exit_info_1;
+	u64 sw_exit_info_2;
+	u64 sw_scratch;
+	u64 sev_features;
+	u8 reserved_11[48];
+	u64 xcr0;
+	u8 valid_bitmap[16];
+	u64 x87_state_gpa;
 };
 
 struct __attribute__ ((__packed__)) vmcb {
diff --git a/tools/testing/selftests/kvm/include/x86_64/svm_util.h b/tools/testing/selftests/kvm/include/x86_64/svm_util.h
index b7531c83b8ae..4319bb6f4691 100644
--- a/tools/testing/selftests/kvm/include/x86_64/svm_util.h
+++ b/tools/testing/selftests/kvm/include/x86_64/svm_util.h
@@ -16,6 +16,7 @@
 #define CPUID_SVM_BIT		2
 #define CPUID_SVM		BIT_ULL(CPUID_SVM_BIT)
 
+#define SVM_EXIT_CPUID		0x072
 #define SVM_EXIT_VMMCALL	0x081
 
 struct svm_test_data {
diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c b/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
new file mode 100644
index 000000000000..b3f7b0297e5b
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
@@ -0,0 +1,249 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * GHCB/#VC/instruction helpers for use with SEV-ES/SEV-SNP guests.
+ *
+ * Partially copied from arch/x86/kernel/sev*.c
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+
+#include <linux/bitops.h>
+#include <kvm_util.h>			/* needed by kvm_util_internal.h */
+#include "../kvm_util_internal.h"	/* needed by processor.h */
+#include "processor.h"			/* for struct ex_regs */
+#include "svm_util.h"			/* for additional SVM_EXIT_* definitions */
+#include "svm.h"			/* for VMCB/VMSA layout */
+#include "sev_exitlib.h"
+
+#define PAGE_SHIFT 12
+
+#define MSR_SEV_ES_GHCB 0xc0010130
+
+#define VMGEXIT() { asm volatile("rep; vmmcall\n\r"); }
+
+#define GHCB_PROTOCOL_MAX	1
+#define GHCB_DEFAULT_USAGE	0
+
+/* Guest-requested termination codes */
+#define GHCB_TERMINATE 0x100UL
+#define GHCB_TERMINATE_REASON(reason_set, reason_val)	\
+	(((((u64)reason_set) &  0x7) << 12) |			\
+	 ((((u64)reason_val) & 0xff) << 16))
+
+#define GHCB_TERMINATE_REASON_UNSPEC 0
+
+/* GHCB MSR protocol for CPUID */
+#define GHCB_CPUID_REQ_EAX 0
+#define GHCB_CPUID_REQ_EBX 1
+#define GHCB_CPUID_REQ_ECX 2
+#define GHCB_CPUID_REQ_EDX 3
+#define GHCB_CPUID_REQ_CODE 0x4UL
+#define GHCB_CPUID_REQ(fn, reg) \
+	(GHCB_CPUID_REQ_CODE | (((uint64_t)reg & 3) << 30) | (((uint64_t)fn) << 32))
+#define GHCB_CPUID_RESP_CODE 0x5UL
+#define GHCB_CPUID_RESP(resp) ((resp) & 0xfff)
+
+/* GHCB MSR protocol for GHCB registration */
+#define GHCB_REG_GPA_REQ_CODE 0x12UL
+#define GHCB_REG_GPA_REQ(gfn) \
+	(((unsigned long)((gfn) & GENMASK_ULL(51, 0)) << 12) | GHCB_REG_GPA_REQ_CODE)
+#define GHCB_REG_GPA_RESP_CODE 0x13UL
+#define GHCB_REG_GPA_RESP(resp) ((resp) & GENMASK_ULL(11, 0))
+#define GHCB_REG_GPA_RESP_VAL(resp) ((resp) >> 12)
+
+/* GHCB format/accessors */
+
+struct ghcb {
+	struct vmcb_save_area save;
+	u8 reserved_save[2048 - sizeof(struct vmcb_save_area)];
+	u8 shared_buffer[2032];
+	u8 reserved_1[10];
+	u16 protocol_version;
+	u32 ghcb_usage;
+};
+
+#define GHCB_BITMAP_IDX(field)							\
+	(offsetof(struct vmcb_save_area, field) / sizeof(u64))
+
+#define DEFINE_GHCB_ACCESSORS(field)						\
+	static inline bool ghcb_##field##_is_valid(const struct ghcb *ghcb)	\
+	{									\
+		return test_bit(GHCB_BITMAP_IDX(field),				\
+				(unsigned long *)&ghcb->save.valid_bitmap);	\
+	}									\
+										\
+	static inline u64 ghcb_get_##field(struct ghcb *ghcb)			\
+	{									\
+		return ghcb->save.field;					\
+	}									\
+										\
+	static inline u64 ghcb_get_##field##_if_valid(struct ghcb *ghcb)	\
+	{									\
+		return ghcb_##field##_is_valid(ghcb) ? ghcb->save.field : 0;	\
+	}									\
+										\
+	static inline void ghcb_set_##field(struct ghcb *ghcb, u64 value)	\
+	{									\
+		__set_bit(GHCB_BITMAP_IDX(field),				\
+			  (unsigned long *)&ghcb->save.valid_bitmap);		\
+		ghcb->save.field = value;					\
+	}
+
+DEFINE_GHCB_ACCESSORS(cpl)
+DEFINE_GHCB_ACCESSORS(rip)
+DEFINE_GHCB_ACCESSORS(rsp)
+DEFINE_GHCB_ACCESSORS(rax)
+DEFINE_GHCB_ACCESSORS(rcx)
+DEFINE_GHCB_ACCESSORS(rdx)
+DEFINE_GHCB_ACCESSORS(rbx)
+DEFINE_GHCB_ACCESSORS(rbp)
+DEFINE_GHCB_ACCESSORS(rsi)
+DEFINE_GHCB_ACCESSORS(rdi)
+DEFINE_GHCB_ACCESSORS(r8)
+DEFINE_GHCB_ACCESSORS(r9)
+DEFINE_GHCB_ACCESSORS(r10)
+DEFINE_GHCB_ACCESSORS(r11)
+DEFINE_GHCB_ACCESSORS(r12)
+DEFINE_GHCB_ACCESSORS(r13)
+DEFINE_GHCB_ACCESSORS(r14)
+DEFINE_GHCB_ACCESSORS(r15)
+DEFINE_GHCB_ACCESSORS(sw_exit_code)
+DEFINE_GHCB_ACCESSORS(sw_exit_info_1)
+DEFINE_GHCB_ACCESSORS(sw_exit_info_2)
+DEFINE_GHCB_ACCESSORS(sw_scratch)
+DEFINE_GHCB_ACCESSORS(xcr0)
+
+static uint64_t sev_es_rdmsr_ghcb(void)
+{
+	uint64_t lo, hi;
+
+	asm volatile("rdmsr"
+		     : "=a" (lo), "=d" (hi)
+		     : "c" (MSR_SEV_ES_GHCB));
+
+	return ((hi << 32) | lo);
+}
+
+static void sev_es_wrmsr_ghcb(uint64_t val)
+{
+	uint64_t lo, hi;
+
+	lo = val & 0xFFFFFFFF;
+	hi = val >> 32;
+
+	asm volatile("wrmsr"
+		     :: "c" (MSR_SEV_ES_GHCB), "a" (lo), "d" (hi)
+		     : "memory");
+}
+
+void sev_es_terminate(int reason)
+{
+	uint64_t val = GHCB_TERMINATE;
+
+	val |= GHCB_TERMINATE_REASON(2, reason);
+
+	sev_es_wrmsr_ghcb(val);
+	VMGEXIT();
+
+	while (true)
+		asm volatile("hlt" : : : "memory");
+}
+
+static int sev_es_ghcb_hv_call(struct ghcb *ghcb, u64 ghcb_gpa, u64 exit_code)
+{
+	ghcb->protocol_version = GHCB_PROTOCOL_MAX;
+	ghcb->ghcb_usage = GHCB_DEFAULT_USAGE;
+
+	ghcb_set_sw_exit_code(ghcb, exit_code);
+	ghcb_set_sw_exit_info_1(ghcb, 0);
+	ghcb_set_sw_exit_info_2(ghcb, 0);
+
+	sev_es_wrmsr_ghcb(ghcb_gpa);
+
+	VMGEXIT();
+
+	/* Only #VC exceptions are currently handled. */
+	if ((ghcb->save.sw_exit_info_1 & 0xffffffff) == 1)
+		sev_es_terminate(GHCB_TERMINATE_REASON_UNSPEC);
+
+	return 0;
+}
+
+static int handle_vc_cpuid(struct ghcb *ghcb, u64 ghcb_gpa, struct ex_regs *regs)
+{
+	int ret;
+
+	ghcb_set_rax(ghcb, regs->rax);
+	ghcb_set_rcx(ghcb, regs->rcx);
+
+	/* ignore additional XSAVE states for now */
+	ghcb_set_xcr0(ghcb, 1);
+
+	ret = sev_es_ghcb_hv_call(ghcb, ghcb_gpa, SVM_EXIT_CPUID);
+	if (ret)
+		return ret;
+
+	if (!(ghcb_rax_is_valid(ghcb) &&
+	      ghcb_rbx_is_valid(ghcb) &&
+	      ghcb_rcx_is_valid(ghcb) &&
+	      ghcb_rdx_is_valid(ghcb)))
+		return 1;
+
+	regs->rax = ghcb->save.rax;
+	regs->rbx = ghcb->save.rbx;
+	regs->rcx = ghcb->save.rcx;
+	regs->rdx = ghcb->save.rdx;
+
+	regs->rip += 2;
+
+	return 0;
+}
+
+static int handle_msr_vc_cpuid(struct ex_regs *regs)
+{
+	uint32_t fn = regs->rax & 0xFFFFFFFF;
+	uint64_t resp;
+
+	sev_es_wrmsr_ghcb(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EAX));
+	VMGEXIT();
+	resp = sev_es_rdmsr_ghcb();
+	if (GHCB_CPUID_RESP(resp) != GHCB_CPUID_RESP_CODE)
+		return 1;
+	regs->rax = resp >> 32;
+
+	sev_es_wrmsr_ghcb(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EBX));
+	VMGEXIT();
+	resp = sev_es_rdmsr_ghcb();
+	if (GHCB_CPUID_RESP(resp) != GHCB_CPUID_RESP_CODE)
+		return 1;
+	regs->rbx = resp >> 32;
+
+	sev_es_wrmsr_ghcb(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_ECX));
+	VMGEXIT();
+	resp = sev_es_rdmsr_ghcb();
+	if (GHCB_CPUID_RESP(resp) != GHCB_CPUID_RESP_CODE)
+		return 1;
+	regs->rcx = resp >> 32;
+
+	sev_es_wrmsr_ghcb(GHCB_CPUID_REQ(fn, GHCB_CPUID_REQ_EDX));
+	VMGEXIT();
+	resp = sev_es_rdmsr_ghcb();
+	if (GHCB_CPUID_RESP(resp) != GHCB_CPUID_RESP_CODE)
+		return 1;
+	regs->rdx = resp >> 32;
+
+	regs->rip += 2;
+
+	return 0;
+}
+
+int sev_es_handle_vc(void *ghcb, u64 ghcb_gpa, struct ex_regs *regs)
+{
+	if (regs->error_code != SVM_EXIT_CPUID)
+		return 1;
+
+	if (!ghcb)
+		return handle_msr_vc_cpuid(regs);
+
+	return handle_vc_cpuid(ghcb, ghcb_gpa, regs);
+}
-- 
2.25.1

[RFC 12/16] KVM: selftests: add SEV-ES boot tests

[Michael Roth]

Extend the existing SEV boot tests to also cover SEV-ES guests. Also
add some tests for handling #VC exceptions for cpuid instructions using
both MSR-based and GHCB-based vmgexits.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../selftests/kvm/x86_64/sev_all_boot_test.c  | 63 ++++++++++++++++++-
 1 file changed, 62 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
index 8df7143ac17d..58c57c4c0ec1 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
@@ -18,6 +18,7 @@
 #include "svm_util.h"
 #include "linux/psp-sev.h"
 #include "sev.h"
+#include "sev_exitlib.h"
 
 #define VCPU_ID			2
 #define PAGE_SIZE		4096
@@ -31,6 +32,10 @@
 
 #define TOTAL_PAGES		(512 + SHARED_PAGES + PRIVATE_PAGES)
 
+/* Globals for use by #VC handler. */
+static void *ghcb0_gva;
+static vm_paddr_t ghcb0_gpa;
+
 static void fill_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
 {
 	int i, j;
@@ -171,6 +176,47 @@ guest_sev_code(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private
 	guest_test_done(sync);
 }
 
+static void vc_handler(struct ex_regs *regs)
+{
+	sev_es_handle_vc(ghcb0_gva, ghcb0_gpa, regs);
+}
+
+static void __attribute__((__flatten__))
+guest_sev_es_code(struct sev_sync_data *sync, uint8_t *shared_buf,
+		  uint8_t *private_buf, uint64_t ghcb_gpa, void *ghcb_gva)
+{
+	uint32_t eax, ebx, ecx, edx, token = 1;
+	uint64_t sev_status;
+
+	guest_test_start(sync);
+
+again:
+	/* Check CPUID values via GHCB MSR protocol. */
+	eax = 0x8000001f;
+	ecx = 0;
+	cpuid(&eax, &ebx, &ecx, &edx);
+
+	/* Check SEV bit. */
+	SEV_GUEST_ASSERT(sync, token++, eax & (1 << 1));
+	/* Check SEV-ES bit. */
+	SEV_GUEST_ASSERT(sync, token++, eax & (1 << 3));
+
+	if (!ghcb0_gva) {
+		ghcb0_gva = ghcb_gva;
+		ghcb0_gpa = ghcb_gpa;
+		/* Check CPUID bits again using GHCB-based protocol. */
+		goto again;
+	}
+
+	/* Check SEV and SEV-ES enabled bits (bits 0 and 1, respectively). */
+	sev_status = rdmsr(MSR_AMD64_SEV);
+	SEV_GUEST_ASSERT(sync, token++, (sev_status & 0x3) == 3);
+
+	guest_test_common(sync, shared_buf, private_buf);
+
+	guest_test_done(sync);
+}
+
 static void
 setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr,
 		  vm_vaddr_t *shared_vaddr, vm_vaddr_t *private_vaddr)
@@ -216,7 +262,18 @@ static void test_sev(void *guest_code, uint64_t policy)
 	setup_test_common(sev, guest_code, &sync_vaddr, &shared_vaddr, &private_vaddr);
 
 	/* Set up guest params. */
-	vcpu_args_set(vm, VCPU_ID, 4, sync_vaddr, shared_vaddr, private_vaddr);
+	if (policy & SEV_POLICY_ES) {
+		vm_vaddr_t ghcb_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0);
+
+		vcpu_args_set(vm, VCPU_ID, 6, sync_vaddr, shared_vaddr, private_vaddr,
+			      addr_gva2gpa(vm, ghcb_vaddr), ghcb_vaddr);
+		/* Set up VC handler. */
+		vm_init_descriptor_tables(vm);
+		vm_install_exception_handler(vm, 29, vc_handler);
+		vcpu_init_descriptor_tables(vm, VCPU_ID);
+	} else {
+		vcpu_args_set(vm, VCPU_ID, 4, sync_vaddr, shared_vaddr, private_vaddr);
+	}
 
 	sync = addr_gva2hva(vm, sync_vaddr);
 	shared_buf = addr_gva2hva(vm, shared_vaddr);
@@ -248,5 +305,9 @@ int main(int argc, char *argv[])
 	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
 	test_sev(guest_sev_code, 0);
 
+	/* SEV-ES tests */
+	test_sev(guest_sev_es_code, SEV_POLICY_ES | SEV_POLICY_NO_DBG);
+	test_sev(guest_sev_es_code, SEV_POLICY_ES);
+
 	return 0;
 }
-- 
2.25.1

[RFC 13/16] KVM: selftests: add support for creating SEV-SNP guests

[Michael Roth]

SEV-SNP uses an entirely different set of KVM_SEV_* ioctls to manage
guests. The needed vm_memcrypt callbacks are different as well. Address
these differences by extending the SEV library with a new set of
interfaces specific to creating/managing SEV-SNP guests.

These guests will still use a struct sev_vm under the covers, so some
existing sev_*() helpers are still applicable.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../selftests/kvm/include/x86_64/sev.h        |  8 ++
 tools/testing/selftests/kvm/lib/x86_64/sev.c  | 77 ++++++++++++++++++-
 2 files changed, 82 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
index d2f41b131ecc..f3e088c03bdd 100644
--- a/tools/testing/selftests/kvm/include/x86_64/sev.h
+++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
@@ -18,6 +18,10 @@
 #define SEV_POLICY_NO_DBG	(1UL << 0)
 #define SEV_POLICY_ES		(1UL << 2)
 
+#define SNP_POLICY_SMT		(1ULL << 16)
+#define SNP_POLICY_RSVD		(1ULL << 17)
+#define SNP_POLICY_DBG		(1ULL << 19)
+
 #define SEV_GUEST_ASSERT(sync, token, _cond) do {	\
 	if (!(_cond))					\
 		sev_guest_abort(sync, token, 0);	\
@@ -59,4 +63,8 @@ void sev_vm_launch(struct sev_vm *sev);
 void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
 void sev_vm_launch_finish(struct sev_vm *sev);
 
+struct sev_vm *sev_snp_vm_create(uint64_t policy, uint64_t npages);
+void sev_snp_vm_free(struct sev_vm *sev);
+void sev_snp_vm_launch(struct sev_vm *sev);
+
 #endif /* SELFTEST_KVM_SEV_H */
diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
index d01b0f637ced..939d7d5dff41 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/sev.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
@@ -20,6 +20,7 @@ struct sev_vm {
 	int fd;
 	int enc_bit;
 	uint32_t sev_policy;
+	uint64_t snp_policy;
 };
 
 /* Helpers for coordinating between guests and test harness. */
@@ -119,6 +120,12 @@ void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
 
 /* Local helpers. */
 
+static bool sev_snp_enabled(struct sev_vm *sev)
+{
+	/* RSVD is always 1 for SNP guests. */
+	return sev->snp_policy & SNP_POLICY_RSVD;
+}
+
 static void
 sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)
 {
@@ -147,6 +154,21 @@ sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
 	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
 }
 
+static void
+sev_snp_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
+{
+	struct kvm_sev_snp_launch_update update_data = {0};
+
+	pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
+
+	update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
+	update_data.start_gfn = gpa >> PAGE_SHIFT;
+	update_data.len = size;
+	update_data.page_type = KVM_SEV_SNP_PAGE_TYPE_NORMAL;
+
+	kvm_sev_ioctl(sev, KVM_SEV_SNP_LAUNCH_UPDATE, &update_data);
+}
+
 static void sev_encrypt(struct sev_vm *sev)
 {
 	struct sparsebit *enc_phy_pages;
@@ -171,9 +193,14 @@ static void sev_encrypt(struct sev_vm *sev)
 		if (pg_cnt <= 0)
 			pg_cnt = 1;
 
-		sev_encrypt_phy_range(sev,
-				      gpa_start + pg * vm_get_page_size(vm),
-				      pg_cnt * vm_get_page_size(vm));
+		if (sev_snp_enabled(sev))
+			sev_snp_encrypt_phy_range(sev,
+						  gpa_start + pg * vm_get_page_size(vm),
+						  pg_cnt * vm_get_page_size(vm));
+		else
+			sev_encrypt_phy_range(sev,
+					      gpa_start + pg * vm_get_page_size(vm),
+					      pg_cnt * vm_get_page_size(vm));
 		pg += pg_cnt;
 	}
 
@@ -308,3 +335,47 @@ void sev_vm_launch_finish(struct sev_vm *sev)
 	TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
 		    "Unexpected guest state: %d", ksev_status.state);
 }
+
+/* SEV-SNP VM implementation. */
+
+struct sev_vm *sev_snp_vm_create(uint64_t policy, uint64_t npages)
+{
+	struct kvm_snp_init init = {0};
+	struct sev_vm *sev;
+	struct kvm_vm *vm;
+
+	vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
+	sev = sev_common_create(vm);
+	if (!sev)
+		return NULL;
+	sev->snp_policy = policy | SNP_POLICY_RSVD;
+
+	kvm_sev_ioctl(sev, KVM_SEV_SNP_INIT, &init);
+	vm_set_memory_encryption(vm, true, true, sev->enc_bit);
+	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
+	sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
+
+	pr_info("SEV-SNP guest created, policy: 0x%lx, size: %lu KB\n",
+		sev->snp_policy, npages * vm_get_page_size(vm) / 1024);
+
+	return sev;
+}
+
+void sev_snp_vm_free(struct sev_vm *sev)
+{
+	kvm_vm_free(sev->vm);
+	sev_common_free(sev);
+}
+
+void sev_snp_vm_launch(struct sev_vm *sev)
+{
+	struct kvm_sev_snp_launch_start launch_start = {0};
+	struct kvm_sev_snp_launch_update launch_finish = {0};
+
+	launch_start.policy = sev->snp_policy;
+	kvm_sev_ioctl(sev, KVM_SEV_SNP_LAUNCH_START, &launch_start);
+
+	sev_encrypt(sev);
+
+	kvm_sev_ioctl(sev, KVM_SEV_SNP_LAUNCH_FINISH, &launch_finish);
+}
-- 
2.25.1

[RFC 14/16] KVM: selftests: add helpers for SEV-SNP-related instructions/exits

[Michael Roth]

Extend the existing sev_exitlib with helpers for handling pvalidate
instructions and issuing page-state changes via the GHCB MSR protocol.

Subsequent SEV-SNP-related tests will make use of these in guest code.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../kvm/include/x86_64/sev_exitlib.h          |  6 ++
 .../selftests/kvm/lib/x86_64/sev_exitlib.c    | 77 +++++++++++++++++++
 2 files changed, 83 insertions(+)

diff --git a/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h b/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
index 4b67b4004dfa..5c7356f9e925 100644
--- a/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
+++ b/tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
@@ -8,7 +8,13 @@
 #ifndef SELFTEST_KVM_SEV_EXITLIB_H
 #define SELFTEST_KVM_SEV_EXITLIB_H
 
+#define PVALIDATE_NO_UPDATE 255
+
 int sev_es_handle_vc(void *ghcb, u64 ghcb_gpa, struct ex_regs *regs);
 void sev_es_terminate(int reason);
+void snp_register_ghcb(u64 ghcb_gpa);
+void snp_psc_set_shared(u64 gpa);
+void snp_psc_set_private(u64 gpa);
+int snp_pvalidate(void *ptr, bool rmp_psize, bool validate);
 
 #endif /* SELFTEST_KVM_SEV_EXITLIB_H */
diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c b/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
index b3f7b0297e5b..546b402d5015 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
@@ -51,6 +51,19 @@
 #define GHCB_REG_GPA_RESP(resp) ((resp) & GENMASK_ULL(11, 0))
 #define GHCB_REG_GPA_RESP_VAL(resp) ((resp) >> 12)
 
+/* GHCB MSR protocol for Page State Change */
+#define GHCB_PSC_REQ_PRIVATE		1
+#define GHCB_PSC_REQ_SHARED		2
+#define GHCB_PSC_REQ_PSMASH		3
+#define GHCB_PSC_REQ_UNSMASH		4
+#define GHCB_PSC_REQ_CODE		0x14UL
+#define GHCB_PSC_REQ(gfn, op)		\
+	(((unsigned long)((op) & 0xf) << 52) |  \
+	 ((unsigned long)((gfn) & ~(1ULL << 40)) << 12) | \
+	 GHCB_PSC_REQ_CODE)
+#define GHCB_PSC_RESP_CODE		0x15UL
+#define GHCB_PSC_RESP(resp)		((resp) & GENMASK_ULL(11, 0))
+
 /* GHCB format/accessors */
 
 struct ghcb {
@@ -247,3 +260,67 @@ int sev_es_handle_vc(void *ghcb, u64 ghcb_gpa, struct ex_regs *regs)
 
 	return handle_vc_cpuid(ghcb, ghcb_gpa, regs);
 }
+
+void snp_register_ghcb(u64 ghcb_gpa)
+{
+	u64 gfn = ghcb_gpa >> PAGE_SHIFT;
+	u64 resp;
+
+	sev_es_wrmsr_ghcb(GHCB_REG_GPA_REQ(gfn));
+	VMGEXIT();
+
+	resp = sev_es_rdmsr_ghcb();
+	if (GHCB_REG_GPA_RESP(resp) != GHCB_REG_GPA_RESP_CODE ||
+	    GHCB_REG_GPA_RESP_VAL(resp) != gfn)
+		sev_es_terminate(GHCB_TERMINATE_REASON_UNSPEC);
+}
+
+static void snp_psc_request(u64 gfn, int op)
+{
+	u64 resp;
+
+	sev_es_wrmsr_ghcb(GHCB_PSC_REQ(gfn, op));
+	VMGEXIT();
+
+	resp = sev_es_rdmsr_ghcb();
+	if (GHCB_PSC_RESP(resp) != GHCB_PSC_RESP_CODE)
+		sev_es_terminate(GHCB_TERMINATE_REASON_UNSPEC);
+}
+
+void snp_psc_set_shared(u64 gpa)
+{
+	snp_psc_request(gpa >> PAGE_SHIFT, GHCB_PSC_REQ_SHARED);
+}
+
+void snp_psc_set_private(u64 gpa)
+{
+	snp_psc_request(gpa >> PAGE_SHIFT, GHCB_PSC_REQ_PRIVATE);
+}
+
+/* From arch/x86/include/asm/asm.h */
+#ifdef __GCC_ASM_FLAG_OUTPUTS__
+# define CC_SET(c) "\n\t/* output condition code " #c "*/\n"
+# define CC_OUT(c) "=@cc" #c
+#else
+# define CC_SET(c) "\n\tset" #c " %[_cc_" #c "]\n"
+# define CC_OUT(c) [_cc_ ## c] "=qm"
+#endif
+
+int snp_pvalidate(void *ptr, bool rmp_psize, bool validate)
+{
+	uint64_t gva = (uint64_t)ptr;
+	bool no_rmpupdate;
+	int rc;
+
+	/* "pvalidate" mnemonic support in binutils 2.36 and newer */
+	asm volatile(".byte 0xF2, 0x0F, 0x01, 0xFF\n\t"
+		     CC_SET(c)
+		     : CC_OUT(c) (no_rmpupdate), "=a"(rc)
+		     : "a"(gva), "c"(rmp_psize), "d"(validate)
+		     : "memory", "cc");
+
+	if (no_rmpupdate)
+		return PVALIDATE_NO_UPDATE;
+
+	return rc;
+}
-- 
2.25.1

[RFC 15/16] KVM: selftests: add SEV-SNP boot tests

[Michael Roth]

Extend the existing SEV/SEV-ES boot tests to also cover SEV-SNP guests.
Also add a basic test to check validation state of initial guest memory.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../selftests/kvm/include/x86_64/svm_util.h   |  1 +
 .../selftests/kvm/x86_64/sev_all_boot_test.c  | 86 +++++++++++++++----
 2 files changed, 71 insertions(+), 16 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/x86_64/svm_util.h b/tools/testing/selftests/kvm/include/x86_64/svm_util.h
index 4319bb6f4691..6c51fc304ce9 100644
--- a/tools/testing/selftests/kvm/include/x86_64/svm_util.h
+++ b/tools/testing/selftests/kvm/include/x86_64/svm_util.h
@@ -18,6 +18,7 @@
 
 #define SVM_EXIT_CPUID		0x072
 #define SVM_EXIT_VMMCALL	0x081
+#define SVM_EXIT_NOT_VALIDATED	0x404
 
 struct svm_test_data {
 	/* VMCB */
diff --git a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
index 58c57c4c0ec1..3d8048efa25f 100644
--- a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
+++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
@@ -217,6 +217,48 @@ guest_sev_es_code(struct sev_sync_data *sync, uint8_t *shared_buf,
 	guest_test_done(sync);
 }
 
+static void __attribute__((__flatten__))
+guest_sev_snp_code(struct sev_sync_data *sync, uint8_t *shared_buf,
+		   uint8_t *private_buf, uint64_t ghcb_gpa, void *ghcb_gva)
+{
+	uint32_t eax, ebx, ecx, edx, token = 1;
+	uint64_t sev_status;
+	int ret;
+
+	guest_test_start(sync);
+
+again:
+	/* Check CPUID values via GHCB MSR protocol. */
+	eax = 0x8000001f;
+	ecx = 0;
+	cpuid(&eax, &ebx, &ecx, &edx);
+
+	/* Check SEV bit. */
+	SEV_GUEST_ASSERT(sync, token++, eax & (1 << 1));
+	/* Check SEV-ES bit. */
+	SEV_GUEST_ASSERT(sync, token++, eax & (1 << 3));
+
+	if (!ghcb0_gva) {
+		ghcb0_gva = ghcb_gva;
+		ghcb0_gpa = ghcb_gpa;
+		snp_register_ghcb(ghcb0_gpa);
+		/* Check CPUID bits again using GHCB-based protocol. */
+		goto again;
+	}
+
+	/* Check SEV/SEV-ES/SEV-SNP enabled bits (bits 0, 1, and 3, respectively). */
+	sev_status = rdmsr(MSR_AMD64_SEV);
+	SEV_GUEST_ASSERT(sync, token++, (sev_status & 0x7) == 7);
+
+	/* Confirm private data was validated by FW prior to boot. */
+	ret = snp_pvalidate(private_buf, 0, true);
+	SEV_GUEST_ASSERT(sync, token++, ret == PVALIDATE_NO_UPDATE);
+
+	guest_test_common(sync, shared_buf, private_buf);
+
+	guest_test_done(sync);
+}
+
 static void
 setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr,
 		  vm_vaddr_t *shared_vaddr, vm_vaddr_t *private_vaddr)
@@ -244,7 +286,7 @@ setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr,
 	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
 }
 
-static void test_sev(void *guest_code, uint64_t policy)
+static void test_sev(void *guest_code, bool snp, uint64_t policy)
 {
 	vm_vaddr_t sync_vaddr, shared_vaddr, private_vaddr;
 	uint8_t *shared_buf, *private_buf;
@@ -254,7 +296,8 @@ static void test_sev(void *guest_code, uint64_t policy)
 	struct kvm_vm *vm;
 	int i;
 
-	sev = sev_vm_create(policy, TOTAL_PAGES);
+	sev = snp ? sev_snp_vm_create(policy, TOTAL_PAGES)
+		  : sev_vm_create(policy, TOTAL_PAGES);
 	if (!sev)
 		return;
 	vm = sev_get_vm(sev);
@@ -262,7 +305,7 @@ static void test_sev(void *guest_code, uint64_t policy)
 	setup_test_common(sev, guest_code, &sync_vaddr, &shared_vaddr, &private_vaddr);
 
 	/* Set up guest params. */
-	if (policy & SEV_POLICY_ES) {
+	if (snp || (policy & SEV_POLICY_ES)) {
 		vm_vaddr_t ghcb_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0);
 
 		vcpu_args_set(vm, VCPU_ID, 6, sync_vaddr, shared_vaddr, private_vaddr,
@@ -280,34 +323,45 @@ static void test_sev(void *guest_code, uint64_t policy)
 	private_buf = addr_gva2hva(vm, private_vaddr);
 
 	/* Allocations/setup done. Encrypt initial guest payload. */
-	sev_vm_launch(sev);
+	if (snp) {
+		sev_snp_vm_launch(sev);
+	} else {
+		sev_vm_launch(sev);
 
-	/* Dump the initial measurement. A test to actually verify it would be nice. */
-	sev_vm_measure(sev, measurement);
-	pr_info("guest measurement: ");
-	for (i = 0; i < 32; ++i)
-		pr_info("%02x", measurement[i]);
-	pr_info("\n");
+		/* Dump the initial measurement. A test to actually verify it would be nice. */
+		sev_vm_measure(sev, measurement);
+		pr_info("guest measurement: ");
+		for (i = 0; i < 32; ++i)
+			pr_info("%02x", measurement[i]);
+		pr_info("\n");
 
-	sev_vm_launch_finish(sev);
+		sev_vm_launch_finish(sev);
+	}
 
 	/* Guest is ready to run. Do the tests. */
 	check_test_start(vm, sync);
 	check_test_common(vm, sync, shared_buf, private_buf);
 	check_test_done(vm, sync);
 
-	sev_vm_free(sev);
+	if (snp)
+		sev_snp_vm_free(sev);
+	else
+		sev_vm_free(sev);
 }
 
 int main(int argc, char *argv[])
 {
 	/* SEV tests */
-	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
-	test_sev(guest_sev_code, 0);
+	test_sev(guest_sev_code, false, SEV_POLICY_NO_DBG);
+	test_sev(guest_sev_code, false, 0);
 
 	/* SEV-ES tests */
-	test_sev(guest_sev_es_code, SEV_POLICY_ES | SEV_POLICY_NO_DBG);
-	test_sev(guest_sev_es_code, SEV_POLICY_ES);
+	test_sev(guest_sev_es_code, false, SEV_POLICY_ES | SEV_POLICY_NO_DBG);
+	test_sev(guest_sev_es_code, false, SEV_POLICY_ES);
+
+	/* SEV-SNP tests */
+	test_sev(guest_sev_snp_code, true, SNP_POLICY_SMT);
+	test_sev(guest_sev_snp_code, true, SNP_POLICY_SMT | SNP_POLICY_DBG);
 
 	return 0;
 }
-- 
2.25.1

[RFC 16/16] KVM: selftests: add SEV-SNP tests for page-state changes

[Michael Roth]

With SEV-SNP guests memory is marked as private/shared or
validated/un-validated in the RMP table. Transitioning memory between
these states can be done within a guest via pvalidate instructions and
the page-state changes via GHCB protocol. Add a number of tests to
cover various permutations of the operations across shared/private
guest memory.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/.gitignore        |   1 +
 tools/testing/selftests/kvm/Makefile          |   1 +
 .../selftests/kvm/x86_64/sev_snp_psc_test.c   | 378 ++++++++++++++++++
 3 files changed, 380 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 824f100bec2a..cad9ebe7728d 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -39,6 +39,7 @@
 /x86_64/xss_msr_test
 /x86_64/vmx_pmu_msrs_test
 /x86_64/sev_all_boot_test
+/x86_64/sev_snp_psc_test
 /access_tracking_perf_test
 /demand_paging_test
 /dirty_log_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 7b3261cc60a3..b95fb86f12aa 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -73,6 +73,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/vmx_pmu_msrs_test
 TEST_GEN_PROGS_x86_64 += x86_64/xen_shinfo_test
 TEST_GEN_PROGS_x86_64 += x86_64/xen_vmcall_test
 TEST_GEN_PROGS_x86_64 += x86_64/sev_all_boot_test
+TEST_GEN_PROGS_x86_64 += x86_64/sev_snp_psc_test
 TEST_GEN_PROGS_x86_64 += access_tracking_perf_test
 TEST_GEN_PROGS_x86_64 += demand_paging_test
 TEST_GEN_PROGS_x86_64 += dirty_log_test
diff --git a/tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c b/tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c
new file mode 100644
index 000000000000..695abcd14792
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c
@@ -0,0 +1,378 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * SEV-SNP tests for pvalidate and page-state changes.
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+#include "processor.h"
+#include "svm_util.h"
+#include "linux/psp-sev.h"
+#include "sev.h"
+#include "sev_exitlib.h"
+
+#define VCPU_ID			0
+#define PAGE_SHIFT		12
+#define PAGE_SIZE		(1UL << PAGE_SHIFT)
+#define PAGE_STRIDE		64
+
+/* NOTE: private/shared pages must each number at least 4 and be power of 2. */
+
+#define SHARED_PAGES		512
+#define SHARED_VADDR_MIN	0x1000000
+
+#define PRIVATE_PAGES		512
+#define PRIVATE_VADDR_MIN	(SHARED_VADDR_MIN + SHARED_PAGES * PAGE_SIZE)
+
+#define TOTAL_PAGES		(512 + SHARED_PAGES + PRIVATE_PAGES)
+#define LINEAR_MAP_GVA		(PRIVATE_VADDR_MIN + PRIVATE_PAGES * PAGE_SIZE)
+
+struct pageTableEntry {
+	uint64_t present:1;
+	uint64_t ignored_11_01:11;
+	uint64_t pfn:40;
+	uint64_t ignored_63_52:12;
+};
+
+/* Globals for use by #VC handler and helpers. */
+static int page_not_validated_count;
+static struct sev_sync_data *guest_sync;
+static uint8_t enc_bit;
+
+static void fill_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
+{
+	int i, j;
+
+	for (i = 0; i < pages; i++)
+		for (j = 0; j < PAGE_SIZE; j += stride)
+			buf[i * PAGE_SIZE + j] = val;
+}
+
+static bool check_buf_nostop(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
+{
+	bool matches = true;
+	int i, j;
+
+	for (i = 0; i < pages; i++)
+		for (j = 0; j < PAGE_SIZE; j += stride)
+			if (buf[i * PAGE_SIZE + j] != val)
+				matches = false;
+	return matches;
+}
+
+static bool check_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
+{
+	int i, j;
+
+	for (i = 0; i < pages; i++)
+		for (j = 0; j < PAGE_SIZE; j += stride)
+			if (buf[i * PAGE_SIZE + j] != val)
+				return false;
+
+	return true;
+}
+
+static void vc_handler(struct ex_regs *regs)
+{
+	int ret;
+
+	if (regs->error_code == SVM_EXIT_NOT_VALIDATED) {
+		unsigned long gva;
+
+		page_not_validated_count++;
+
+		asm volatile("mov %%cr2,%0" : "=r" (gva));
+		ret = snp_pvalidate((void *)gva, 0, true);
+		SEV_GUEST_ASSERT(guest_sync, 9001, !ret);
+
+		return;
+	}
+
+	ret = sev_es_handle_vc(NULL, 0, regs);
+	SEV_GUEST_ASSERT(guest_sync, 20000 + regs->error_code, !ret);
+}
+
+#define gpa_mask(gpa) (gpa & ~(1ULL << enc_bit))
+#define gfn_mask(gfn) (gfn & ~((1ULL << enc_bit) >> PAGE_SHIFT))
+#define va(gpa) ((void *)(LINEAR_MAP_GVA + (gpa & ~(1ULL << enc_bit))))
+#define gfn2va(gfn) va(gfn_mask(gfn) * PAGE_SIZE)
+
+static void set_pte_bit(void *ptr, uint8_t pos, bool enable)
+{
+	struct pageTableEntry *pml4e, *pdpe, *pde, *pte;
+	uint16_t index[4];
+	uint64_t *pte_val;
+	uint64_t gva = (uint64_t)ptr;
+
+	index[0] = (gva >> 12) & 0x1FFU;
+	index[1] = (gva >> 21) & 0x1FFU;
+	index[2] = (gva >> 30) & 0x1FFU;
+	index[3] = (gva >> 39) & 0x1FFU;
+
+	pml4e = (struct pageTableEntry *)va(gpa_mask(get_cr3()));
+	SEV_GUEST_ASSERT(guest_sync, 1001, pml4e[index[3]].present);
+
+	pdpe = (struct pageTableEntry *)gfn2va(pml4e[index[3]].pfn);
+	SEV_GUEST_ASSERT(guest_sync, 1002, pdpe[index[2]].present);
+
+	pde = (struct pageTableEntry *)gfn2va(pdpe[index[2]].pfn);
+	SEV_GUEST_ASSERT(guest_sync, 1003, pde[index[1]].present);
+
+	pte = (struct pageTableEntry *)gfn2va(pde[index[1]].pfn);
+	SEV_GUEST_ASSERT(guest_sync, 1004, pte[index[0]].present);
+
+	pte_val = (uint64_t *)&pte[index[0]];
+	if (enable)
+		*pte_val |= (1UL << pos);
+	else
+		*pte_val &= ~(1UL << pos);
+
+	asm volatile("invlpg (%0)" ::"r" (gva) : "memory");
+}
+
+static void guest_test_psc(uint64_t shared_buf_gpa, uint8_t *shared_buf,
+			   uint64_t private_buf_gpa, uint8_t *private_buf)
+{
+	bool success;
+	int rc, i;
+
+	sev_guest_sync(guest_sync, 100, 0);
+
+	/* Flip 1st half of private pages to shared and verify VMM can read them. */
+	for (i = 0; i < (PRIVATE_PAGES / 2); i++) {
+		rc = snp_pvalidate(&private_buf[i * PAGE_SIZE], 0, false);
+		SEV_GUEST_ASSERT(guest_sync, 101, !rc);
+		snp_psc_set_shared(private_buf_gpa + i * PAGE_SIZE);
+		set_pte_bit(&private_buf[i * PAGE_SIZE], enc_bit, false);
+	}
+	fill_buf(private_buf, PRIVATE_PAGES / 2, PAGE_STRIDE, 0x43);
+
+	sev_guest_sync(guest_sync, 200, 0);
+
+	/*
+	 * Flip 2nd half of private pages to shared and hand them to the VMM.
+	 *
+	 * This time leave the C-bit set, which should cause a 0x404
+	 * (PAGE_NOT_VALIDATED) #VC when guest later attempts to access each
+	 * page.
+	 */
+	for (i = PRIVATE_PAGES / 2; i < PRIVATE_PAGES; i++) {
+		rc = snp_pvalidate(&private_buf[i * PAGE_SIZE], 0, false);
+		if (rc)
+			sev_guest_abort(guest_sync, rc, 0);
+		snp_psc_set_shared(private_buf_gpa + i * PAGE_SIZE);
+	}
+
+	sev_guest_sync(guest_sync, 300, 0);
+
+	/*
+	 * VMM has filled up the newly-shared pages, but C-bit is still set, so
+	 * verify the contents still show up as encrypted, and make sure to
+	 * access each to verify #VC records the PAGE_NOT_VALIDATED exceptions.
+	 */
+	WRITE_ONCE(page_not_validated_count, 0);
+	success = check_buf_nostop(&private_buf[(PRIVATE_PAGES / 2) * PAGE_SIZE],
+				   PRIVATE_PAGES / 2, PAGE_STRIDE, 0x44);
+	SEV_GUEST_ASSERT(guest_sync, 301, !success);
+	SEV_GUEST_ASSERT(guest_sync, 302,
+			 READ_ONCE(page_not_validated_count) == (PRIVATE_PAGES / 2));
+
+	/* Now flip the C-bit off and verify the VMM-provided values are intact. */
+	for (i = PRIVATE_PAGES / 2; i < PRIVATE_PAGES; i++)
+		set_pte_bit(&private_buf[i * PAGE_SIZE], enc_bit, false);
+	success = check_buf(&private_buf[(PRIVATE_PAGES / 2) * PAGE_SIZE],
+			    PRIVATE_PAGES / 2, PAGE_STRIDE, 0x44);
+	SEV_GUEST_ASSERT(guest_sync, 303, success);
+
+	/* Flip the 1st half back to private pages. */
+	for (i = 0; i < (PRIVATE_PAGES / 2); i++) {
+		snp_psc_set_private(private_buf_gpa + i * PAGE_SIZE);
+		set_pte_bit(&private_buf[i * PAGE_SIZE], enc_bit, true);
+		rc = snp_pvalidate(&private_buf[i * PAGE_SIZE], 0, true);
+		SEV_GUEST_ASSERT(guest_sync, 304, !rc);
+	}
+	/* Pages are private again, write over them with new encrypted data. */
+	fill_buf(private_buf, PRIVATE_PAGES / 2, PAGE_STRIDE, 0x45);
+
+	sev_guest_sync(guest_sync, 400, 0);
+
+	/*
+	 * Take some private pages and flip the C-bit off. Subsequent access
+	 * should cause an RMP fault, which should lead to the VMM doing a
+	 * PSC to shared on our behalf.
+	 */
+	for (i = 0; i < (PRIVATE_PAGES / 4); i++)
+		set_pte_bit(&private_buf[i * PAGE_SIZE], enc_bit, false);
+	fill_buf(private_buf, PRIVATE_PAGES / 4, PAGE_STRIDE, 0x46);
+
+	sev_guest_sync(guest_sync, 500, 0);
+
+	/* Flip all even-numbered shared pages to private. */
+	for (i = 0; i < SHARED_PAGES; i++) {
+		if ((i % 2) != 0)
+			continue;
+
+		snp_psc_set_private(shared_buf_gpa + i * PAGE_SIZE);
+		set_pte_bit(&shared_buf[i * PAGE_SIZE], enc_bit, true);
+		rc = snp_pvalidate(&shared_buf[i * PAGE_SIZE], 0, true);
+		SEV_GUEST_ASSERT(guest_sync, 501, !rc);
+	}
+
+	/* Write across the entire range and hand it back to VMM to verify. */
+	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x47);
+
+	sev_guest_sync(guest_sync, 600, 0);
+}
+
+static void check_test_psc(struct kvm_vm *vm, struct sev_sync_data *sync,
+			   uint8_t *shared_buf, uint8_t *private_buf)
+{
+	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+	bool success;
+	int i;
+
+	/* Initial check-in for PSC tests. */
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 100);
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 200);
+
+	/* 1st half of private buffer should be shared now, check contents. */
+	success = check_buf(private_buf, PRIVATE_PAGES / 2, PAGE_STRIDE, 0x43);
+	TEST_ASSERT(success, "Unexpected contents in newly-shared buffer.");
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 300);
+
+	/* 2nd half of private buffer should be shared now, write to it. */
+	fill_buf(&private_buf[(PRIVATE_PAGES / 2) * PAGE_SIZE],
+		 PRIVATE_PAGES / 2, PAGE_STRIDE, 0x44);
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 400);
+
+	/* 1st half of private buffer should no longer be shared. Verify. */
+	success = check_buf(private_buf, PRIVATE_PAGES / 2, PAGE_STRIDE, 0x45);
+	TEST_ASSERT(!success, "Unexpected contents in newly-private buffer.");
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 500);
+
+	/* 1st quarter of private buffer should be shared again. Verify. */
+	success = check_buf(private_buf, PRIVATE_PAGES / 4, PAGE_STRIDE, 0x46);
+	TEST_ASSERT(success, "Unexpected contents in newly-shared buffer.");
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 600);
+
+	/* Verify even-numbered pages in shared_buf are now private. */
+	for (i = 0; i < SHARED_PAGES; i++) {
+		success = check_buf(&shared_buf[i * PAGE_SIZE], 1, PAGE_STRIDE, 0x47);
+		if ((i % 2) == 0)
+			TEST_ASSERT(!success, "Private buffer contains plain-text.");
+		else
+			TEST_ASSERT(success, "Shared buffer contains cipher-text.");
+	}
+}
+
+static void __attribute__((__flatten__))
+guest_code(struct sev_sync_data *sync, uint64_t shared_buf_gpa, uint8_t *shared_buf,
+	   uint64_t private_buf_gpa, uint8_t *private_buf)
+{
+	uint32_t eax, ebx, ecx, edx;
+
+	/* Initial check-in. */
+	guest_sync = sync;
+	sev_guest_sync(guest_sync, 1, 0);
+
+	/* Get encryption bit via CPUID. */
+	eax = 0x8000001f;
+	ecx = 0;
+	cpuid(&eax, &ebx, &ecx, &edx);
+	enc_bit = ebx & 0x3F;
+
+	/* Do the tests. */
+	guest_test_psc(shared_buf_gpa, shared_buf, private_buf_gpa, private_buf);
+
+	sev_guest_done(guest_sync, 10000, 0);
+}
+
+int main(int argc, char *argv[])
+{
+	vm_vaddr_t shared_vaddr, private_vaddr, sync_vaddr;
+	uint8_t *shared_buf, *private_buf;
+	struct sev_sync_data *sync;
+	struct kvm_run *run;
+	struct sev_vm *sev;
+	struct kvm_vm *vm;
+
+	/* Create VM and main memslot/region. */
+	sev = sev_snp_vm_create(SNP_POLICY_SMT, TOTAL_PAGES);
+	if (!sev)
+		exit(KSFT_SKIP);
+	vm = sev_get_vm(sev);
+
+	/* Set up VCPU and #VC handler. */
+	vm_vcpu_add_default(vm, VCPU_ID, guest_code);
+	kvm_vm_elf_load(vm, program_invocation_name);
+	vm_init_descriptor_tables(vm);
+	vm_install_exception_handler(vm, 29, vc_handler);
+	vcpu_init_descriptor_tables(vm, VCPU_ID);
+
+	/* Set up shared page for sync buffer. */
+	sync_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0);
+	sync = addr_gva2hva(vm, sync_vaddr);
+
+	/* Set up additional buffer for reserved shared memory. */
+	shared_vaddr = vm_vaddr_alloc_shared(vm, SHARED_PAGES * PAGE_SIZE,
+					     SHARED_VADDR_MIN);
+	shared_buf = addr_gva2hva(vm, shared_vaddr);
+	memset(shared_buf, 0, SHARED_PAGES * PAGE_SIZE);
+
+	/* Set up additional buffer for reserved private memory. */
+	private_vaddr = vm_vaddr_alloc(vm, PRIVATE_PAGES * PAGE_SIZE,
+				       PRIVATE_VADDR_MIN);
+	private_buf = addr_gva2hva(vm, private_vaddr);
+	memset(private_buf, 0, PRIVATE_PAGES * PAGE_SIZE);
+
+	/*
+	 * Create a linear mapping of all guest memory. This will map all pages
+	 * as encrypted, which is okay in this case, because the linear mapping
+	 * will only be used to access page tables, which are always treated
+	 * as encrypted.
+	 */
+	virt_map(vm, LINEAR_MAP_GVA, 1UL << sev_get_enc_bit(sev), TOTAL_PAGES);
+
+	/* Set up guest params. */
+	vcpu_args_set(vm, VCPU_ID, 5, sync_vaddr,
+		      addr_gva2gpa(vm, shared_vaddr), shared_vaddr,
+		      addr_gva2gpa(vm, private_vaddr), private_vaddr);
+
+	/* Encrypt initial guest payload and prepare to run it. */
+	sev_snp_vm_launch(sev);
+
+	/* Initial guest check-in. */
+	run = vcpu_state(vm, VCPU_ID);
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 1);
+
+	/* Do the tests. */
+	check_test_psc(vm, sync, shared_buf, private_buf);
+
+	/* Wait for guest to finish up. */
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_done(run, sync, 10000);
+
+	sev_snp_vm_free(sev);
+
+	return 0;
+}
-- 
2.25.1

[RFC 04/16] KVM: selftests: add library for creating/interacting with SEV guests

[Michael Roth]

Add interfaces to allow tests to create/manage SEV guests. The
additional state associated with these guests is encapsulated in a new
struct sev_vm, which is a light wrapper around struct kvm_vm. These
VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
under the covers to configure and sync up with the core kvm_util
library on what should/shouldn't be treated as encrypted memory.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/Makefile          |   1 +
 .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
 tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
 3 files changed, 366 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 5832f510a16c..c7a5e1c69e0c 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -35,6 +35,7 @@ endif
 
 LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
 LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
+LIBKVM_x86_64 += lib/x86_64/sev.c
 LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
 LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
 
diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
new file mode 100644
index 000000000000..d2f41b131ecc
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Helpers used for SEV guests
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+#ifndef SELFTEST_KVM_SEV_H
+#define SELFTEST_KVM_SEV_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "kvm_util.h"
+
+#define SEV_DEV_PATH		"/dev/sev"
+#define SEV_FW_REQ_VER_MAJOR	1
+#define SEV_FW_REQ_VER_MINOR	30
+
+#define SEV_POLICY_NO_DBG	(1UL << 0)
+#define SEV_POLICY_ES		(1UL << 2)
+
+#define SEV_GUEST_ASSERT(sync, token, _cond) do {	\
+	if (!(_cond))					\
+		sev_guest_abort(sync, token, 0);	\
+} while (0)
+
+enum {
+	SEV_GSTATE_UNINIT = 0,
+	SEV_GSTATE_LUPDATE,
+	SEV_GSTATE_LSECRET,
+	SEV_GSTATE_RUNNING,
+};
+
+struct sev_sync_data {
+	uint32_t token;
+	bool pending;
+	bool done;
+	bool aborted;
+	uint64_t info;
+};
+
+struct sev_vm;
+
+void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info);
+void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info);
+void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info);
+
+void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token);
+void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token);
+
+void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data);
+struct kvm_vm *sev_get_vm(struct sev_vm *sev);
+uint8_t sev_get_enc_bit(struct sev_vm *sev);
+
+struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages);
+void sev_vm_free(struct sev_vm *sev);
+void sev_vm_launch(struct sev_vm *sev);
+void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
+void sev_vm_launch_finish(struct sev_vm *sev);
+
+#endif /* SELFTEST_KVM_SEV_H */
diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
new file mode 100644
index 000000000000..adda3b396566
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
@@ -0,0 +1,303 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Helpers used for SEV guests
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "kvm_util.h"
+#include "linux/psp-sev.h"
+#include "processor.h"
+#include "sev.h"
+
+#define PAGE_SHIFT		12
+#define PAGE_SIZE		(1UL << PAGE_SHIFT)
+
+struct sev_vm {
+	struct kvm_vm *vm;
+	int fd;
+	int enc_bit;
+	uint32_t sev_policy;
+};
+
+/* Helpers for coordinating between guests and test harness. */
+
+void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info)
+{
+	sync->token = token;
+	sync->info = info;
+	sync->pending = true;
+
+	asm volatile("hlt" : : : "memory");
+}
+
+void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
+{
+	while (true) {
+		sync->done = true;
+		sev_guest_sync(sync, token, info);
+	}
+}
+
+void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info)
+{
+	while (true) {
+		sync->aborted = true;
+		sev_guest_sync(sync, token, info);
+	}
+}
+
+void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token)
+{
+	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
+		    "unexpected exit reason: %u (%s)",
+		    run->exit_reason, exit_reason_str(run->exit_reason));
+	TEST_ASSERT(sync->token == token,
+		    "unexpected guest token, expected %d, got: %d", token,
+		    sync->token);
+	TEST_ASSERT(!sync->done, "unexpected guest state");
+	TEST_ASSERT(!sync->aborted, "unexpected guest state");
+	sync->pending = false;
+}
+
+void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token)
+{
+	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
+		    "unexpected exit reason: %u (%s)",
+		    run->exit_reason, exit_reason_str(run->exit_reason));
+	TEST_ASSERT(sync->token == token,
+		    "unexpected guest token, expected %d, got: %d", token,
+		    sync->token);
+	TEST_ASSERT(sync->done, "unexpected guest state");
+	TEST_ASSERT(!sync->aborted, "unexpected guest state");
+	sync->pending = false;
+}
+
+/* Common SEV helpers/accessors. */
+
+struct kvm_vm *sev_get_vm(struct sev_vm *sev)
+{
+	return sev->vm;
+}
+
+uint8_t sev_get_enc_bit(struct sev_vm *sev)
+{
+	return sev->enc_bit;
+}
+
+void sev_ioctl(int sev_fd, int cmd, void *data)
+{
+	int ret;
+	struct sev_issue_cmd arg;
+
+	arg.cmd = cmd;
+	arg.data = (unsigned long)data;
+	ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg);
+	TEST_ASSERT(ret == 0,
+		    "SEV ioctl %d failed, error: %d, fw_error: %d",
+		    cmd, ret, arg.error);
+}
+
+void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
+{
+	struct kvm_sev_cmd arg = {0};
+	int ret;
+
+	arg.id = cmd;
+	arg.sev_fd = sev->fd;
+	arg.data = (__u64)data;
+
+	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_OP, &arg);
+	TEST_ASSERT(ret == 0,
+		    "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d",
+		    cmd, ret, errno, strerror(errno), arg.error);
+}
+
+/* Local helpers. */
+
+static void
+sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)
+{
+	struct kvm_enc_region range = {0};
+	int ret;
+
+	pr_debug("register_user_range: hva: %p, size: %lu\n", hva, size);
+
+	range.addr = (__u64)hva;
+	range.size = size;
+
+	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_REG_REGION, &range);
+	TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno);
+}
+
+static void
+sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
+{
+	struct kvm_sev_launch_update_data ksev_update_data = {0};
+
+	pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
+
+	ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
+	ksev_update_data.len = size;
+
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
+}
+
+static void sev_encrypt(struct sev_vm *sev)
+{
+	struct sparsebit *enc_phy_pages;
+	struct kvm_vm *vm = sev->vm;
+	sparsebit_idx_t pg = 0;
+	vm_paddr_t gpa_start;
+	uint64_t memory_size;
+
+	/* Only memslot 0 supported for now. */
+	enc_phy_pages = vm_get_encrypted_phy_pages(sev->vm, 0, &gpa_start, &memory_size);
+	TEST_ASSERT(enc_phy_pages, "Unable to retrieve encrypted pages bitmap");
+	while (pg < (memory_size / vm_get_page_size(vm))) {
+		sparsebit_idx_t pg_cnt;
+
+		if (sparsebit_is_clear(enc_phy_pages, pg)) {
+			pg = sparsebit_next_set(enc_phy_pages, pg);
+			if (!pg)
+				break;
+		}
+
+		pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg;
+		if (pg_cnt <= 0)
+			pg_cnt = 1;
+
+		sev_encrypt_phy_range(sev,
+				      gpa_start + pg * vm_get_page_size(vm),
+				      pg_cnt * vm_get_page_size(vm));
+		pg += pg_cnt;
+	}
+
+	sparsebit_free(&enc_phy_pages);
+}
+
+/* SEV VM implementation. */
+
+static struct sev_vm *sev_common_create(struct kvm_vm *vm)
+{
+	struct sev_user_data_status sev_status = {0};
+	uint32_t eax, ebx, ecx, edx;
+	struct sev_vm *sev;
+	int sev_fd;
+
+	sev_fd = open(SEV_DEV_PATH, O_RDWR);
+	if (sev_fd < 0) {
+		pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n",
+			SEV_DEV_PATH, sev_fd);
+		return NULL;
+	}
+
+	sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status);
+
+	if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR ||
+	      (sev_status.api_major == SEV_FW_REQ_VER_MAJOR &&
+	       sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) {
+		pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n",
+			sev_status.api_major, sev_status.api_minor, sev_status.build,
+			SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR);
+		return NULL;
+	}
+
+	sev = calloc(1, sizeof(*sev));
+	sev->fd = sev_fd;
+	sev->vm = vm;
+
+	/* Get encryption bit via CPUID. */
+	eax = 0x8000001f;
+	ecx = 0;
+	cpuid(&eax, &ebx, &ecx, &edx);
+	sev->enc_bit = ebx & 0x3F;
+
+	return sev;
+}
+
+static void sev_common_free(struct sev_vm *sev)
+{
+	close(sev->fd);
+	free(sev);
+}
+
+struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
+{
+	struct sev_vm *sev;
+	struct kvm_vm *vm;
+
+	/* Need to handle memslots after init, and after setting memcrypt. */
+	vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
+	sev = sev_common_create(vm);
+	if (!sev)
+		return NULL;
+	sev->sev_policy = policy;
+
+	kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
+
+	vm_set_memory_encryption(vm, true, true, sev->enc_bit);
+	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
+	sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
+
+	pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
+		sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
+
+	return sev;
+}
+
+void sev_vm_free(struct sev_vm *sev)
+{
+	kvm_vm_free(sev->vm);
+	sev_common_free(sev);
+}
+
+void sev_vm_launch(struct sev_vm *sev)
+{
+	struct kvm_sev_launch_start ksev_launch_start = {0};
+	struct kvm_sev_guest_status ksev_status = {0};
+
+	ksev_launch_start.policy = sev->sev_policy;
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start);
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
+	TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy.");
+	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE,
+		    "Unexpected guest state: %d", ksev_status.state);
+
+	sev_encrypt(sev);
+}
+
+void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
+{
+	struct kvm_sev_launch_measure ksev_launch_measure = {0};
+	struct kvm_sev_guest_status ksev_guest_status = {0};
+
+	ksev_launch_measure.len = 256;
+	ksev_launch_measure.uaddr = (__u64)measurement;
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure);
+
+	/* Measurement causes a state transition, check that. */
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status);
+	TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET,
+		    "Unexpected guest state: %d", ksev_guest_status.state);
+}
+
+void sev_vm_launch_finish(struct sev_vm *sev)
+{
+	struct kvm_sev_guest_status ksev_status = {0};
+
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
+	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE ||
+		    ksev_status.state == SEV_GSTATE_LSECRET,
+		    "Unexpected guest state: %d", ksev_status.state);
+
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL);
+
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
+	TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
+		    "Unexpected guest state: %d", ksev_status.state);
+}
-- 
2.25.1

Re: [RFC 04/16] KVM: selftests: add library for creating/interacting with SEV guests

[Michael Roth]

On Wed, Oct 06, 2021 at 03:28:05PM -0500, Michael Roth wrote:
> Add interfaces to allow tests to create/manage SEV guests. The
> additional state associated with these guests is encapsulated in a new
> struct sev_vm, which is a light wrapper around struct kvm_vm. These
> VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
> under the covers to configure and sync up with the core kvm_util
> library on what should/shouldn't be treated as encrypted memory.
> 
> Signed-off-by: Michael Roth <michael.roth@amd.com>

Please ignore this patch, it is a dupe of 06/16. Some patches got caught in our
spam filter and I messed up the numbering when resending this. Hopefully now
all the patches are present.

[RFC 04/16] KVM: selftests: set CPUID before setting sregs in vcpu creation

[Michael Roth]

Recent kernels have checks to ensure the GPA values in special-purpose
registers like CR3 are within the maximum physical address range and
don't overlap with anything in the upper/reserved range. In the case of
SEV kselftest guests booting directly into 64-bit mode, CR3 needs to be
initialized to the GPA of the page table root, with the encryption bit
set. The kernel accounts for this encryption bit by removing it from
reserved bit range when the guest advertises the bit position via
KVM_SET_CPUID*, but kselftests currently call KVM_SET_SREGS as part of
vm_vcpu_add_default(), *prior* to vCPU creation, so there's no
opportunity to call KVM_SET_CPUID* in advance. As a result,
KVM_SET_SREGS will return an error in these cases.

Address this by moving vcpu_set_cpuid() (which calls KVM_SET_CPUID*)
ahead of vcpu_setup() (which calls KVM_SET_SREGS).

While there, address a typo in the assertion that triggers when
KVM_SET_SREGS fails.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/lib/kvm_util.c         | 2 +-
 tools/testing/selftests/kvm/lib/x86_64/processor.c | 4 +---
 2 files changed, 2 insertions(+), 4 deletions(-)

diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index ef88fdc7e46b..646cffd86d09 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1906,7 +1906,7 @@ void vcpu_sregs_get(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
 void vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
 {
 	int ret = _vcpu_sregs_set(vm, vcpuid, sregs);
-	TEST_ASSERT(ret == 0, "KVM_RUN IOCTL failed, "
+	TEST_ASSERT(ret == 0, "KVM_SET_SREGS IOCTL failed, "
 		"rc: %i errno: %i", ret, errno);
 }
 
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 0bbd88fe1127..1ab4c20f5d12 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -660,6 +660,7 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
 
 	/* Create VCPU */
 	vm_vcpu_add(vm, vcpuid);
+	vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
 	vcpu_setup(vm, vcpuid);
 
 	/* Setup guest general purpose registers */
@@ -672,9 +673,6 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
 	/* Setup the MP state */
 	mp_state.mp_state = 0;
 	vcpu_set_mp_state(vm, vcpuid, &mp_state);
-
-	/* Setup supported CPUIDs */
-	vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
 }
 
 /*
-- 
2.25.1

Re: [RFC 04/16] KVM: selftests: set CPUID before setting sregs in vcpu creation

[Nathan Tempelman]

On Wed, Oct 6, 2021 at 1:39 PM Michael Roth <michael.roth@amd.com> wrote:
>
> Recent kernels have checks to ensure the GPA values in special-purpose
> registers like CR3 are within the maximum physical address range and
> don't overlap with anything in the upper/reserved range. In the case of
> SEV kselftest guests booting directly into 64-bit mode, CR3 needs to be
> initialized to the GPA of the page table root, with the encryption bit
> set. The kernel accounts for this encryption bit by removing it from
> reserved bit range when the guest advertises the bit position via
> KVM_SET_CPUID*, but kselftests currently call KVM_SET_SREGS as part of
> vm_vcpu_add_default(), *prior* to vCPU creation, so there's no
> opportunity to call KVM_SET_CPUID* in advance. As a result,
> KVM_SET_SREGS will return an error in these cases.
>
> Address this by moving vcpu_set_cpuid() (which calls KVM_SET_CPUID*)
> ahead of vcpu_setup() (which calls KVM_SET_SREGS).
>
> While there, address a typo in the assertion that triggers when
> KVM_SET_SREGS fails.
>
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>  tools/testing/selftests/kvm/lib/kvm_util.c         | 2 +-
>  tools/testing/selftests/kvm/lib/x86_64/processor.c | 4 +---
>  2 files changed, 2 insertions(+), 4 deletions(-)
>
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index ef88fdc7e46b..646cffd86d09 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -1906,7 +1906,7 @@ void vcpu_sregs_get(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
>  void vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
>  {
>         int ret = _vcpu_sregs_set(vm, vcpuid, sregs);
> -       TEST_ASSERT(ret == 0, "KVM_RUN IOCTL failed, "
> +       TEST_ASSERT(ret == 0, "KVM_SET_SREGS IOCTL failed, "
>                 "rc: %i errno: %i", ret, errno);
>  }
>
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index 0bbd88fe1127..1ab4c20f5d12 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -660,6 +660,7 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
>
>         /* Create VCPU */
>         vm_vcpu_add(vm, vcpuid);
> +       vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
>         vcpu_setup(vm, vcpuid);
>
>         /* Setup guest general purpose registers */
> @@ -672,9 +673,6 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
>         /* Setup the MP state */
>         mp_state.mp_state = 0;
>         vcpu_set_mp_state(vm, vcpuid, &mp_state);
> -
> -       /* Setup supported CPUIDs */
> -       vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
>  }
>
>  /*
> --
> 2.25.1
>

Good catch.
Reviewed-by: Nathan Tempelman <natet@google.com>

Re: [RFC 04/16] KVM: selftests: set CPUID before setting sregs in vcpu creation

[Krish Sadhukhan]

On 10/6/21 1:36 PM, Michael Roth wrote:
> KVM_SET_CPUID*, but kselftests currently call KVM_SET_SREGS as part of
> vm_vcpu_add_default(),*prior*  to vCPU creation, so there's no
> opportunity to call KVM_SET_CPUID* in advance. As a result,
In the current code, I see that KVM_SET_SREGS is called by vcpu_setup() 
which is called after vm_vcpu_add() that calls KVM_CREATE_VCPU. Since 
you mentioned "prior", I wanted to check if the wording was wrong or if 
I missed something.

Re: [RFC 04/16] KVM: selftests: set CPUID before setting sregs in vcpu creation

[Michael Roth]

On Tue, Oct 12, 2021 at 06:45:09PM -0700, Krish Sadhukhan wrote:
> 
> On 10/6/21 1:36 PM, Michael Roth wrote:
> > KVM_SET_CPUID*, but kselftests currently call KVM_SET_SREGS as part of
> > vm_vcpu_add_default(),*prior*  to vCPU creation, so there's no
> > opportunity to call KVM_SET_CPUID* in advance. As a result,
> In the current code, I see that KVM_SET_SREGS is called by vcpu_setup()
> which is called after vm_vcpu_add() that calls KVM_CREATE_VCPU. Since you
> mentioned "prior", I wanted to check if the wording was wrong or if I missed
> something.

Ah, yes, just poorly worded. What I meant to convey is that from the
perspective the test program the vm_vcpu_add* call that creates the vcpu does
the KVM_SET_SREGS, so there's no way to call KVM_SET_CPUID in advance other
than to have vm_vcpu_add* do it as part of creating the vcpu. I get the
wording fixed up on that.

Re: [RFC 04/16] KVM: selftests: set CPUID before setting sregs in vcpu creation

[Paolo Bonzini]

On 06/10/21 22:36, Michael Roth wrote:
> Recent kernels have checks to ensure the GPA values in special-purpose
> registers like CR3 are within the maximum physical address range and
> don't overlap with anything in the upper/reserved range. In the case of
> SEV kselftest guests booting directly into 64-bit mode, CR3 needs to be
> initialized to the GPA of the page table root, with the encryption bit
> set. The kernel accounts for this encryption bit by removing it from
> reserved bit range when the guest advertises the bit position via
> KVM_SET_CPUID*, but kselftests currently call KVM_SET_SREGS as part of
> vm_vcpu_add_default(), *prior* to vCPU creation, so there's no
> opportunity to call KVM_SET_CPUID* in advance. As a result,
> KVM_SET_SREGS will return an error in these cases.
> 
> Address this by moving vcpu_set_cpuid() (which calls KVM_SET_CPUID*)
> ahead of vcpu_setup() (which calls KVM_SET_SREGS).
> 
> While there, address a typo in the assertion that triggers when
> KVM_SET_SREGS fails.
> 
> Suggested-by: Sean Christopherson <seanjc@google.com>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>   tools/testing/selftests/kvm/lib/kvm_util.c         | 2 +-
>   tools/testing/selftests/kvm/lib/x86_64/processor.c | 4 +---
>   2 files changed, 2 insertions(+), 4 deletions(-)
> 
> diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
> index ef88fdc7e46b..646cffd86d09 100644
> --- a/tools/testing/selftests/kvm/lib/kvm_util.c
> +++ b/tools/testing/selftests/kvm/lib/kvm_util.c
> @@ -1906,7 +1906,7 @@ void vcpu_sregs_get(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
>   void vcpu_sregs_set(struct kvm_vm *vm, uint32_t vcpuid, struct kvm_sregs *sregs)
>   {
>   	int ret = _vcpu_sregs_set(vm, vcpuid, sregs);
> -	TEST_ASSERT(ret == 0, "KVM_RUN IOCTL failed, "
> +	TEST_ASSERT(ret == 0, "KVM_SET_SREGS IOCTL failed, "
>   		"rc: %i errno: %i", ret, errno);
>   }
>   
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> index 0bbd88fe1127..1ab4c20f5d12 100644
> --- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
> +++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
> @@ -660,6 +660,7 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
>   
>   	/* Create VCPU */
>   	vm_vcpu_add(vm, vcpuid);
> +	vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
>   	vcpu_setup(vm, vcpuid);
>   
>   	/* Setup guest general purpose registers */
> @@ -672,9 +673,6 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code)
>   	/* Setup the MP state */
>   	mp_state.mp_state = 0;
>   	vcpu_set_mp_state(vm, vcpuid, &mp_state);
> -
> -	/* Setup supported CPUIDs */
> -	vcpu_set_cpuid(vm, vcpuid, kvm_get_supported_cpuid());
>   }
>   
>   /*
> 

Queued, thanks.

Paolo

[RFC 05/16] KVM: selftests: add support for encrypted vm_vaddr_* allocations

[Michael Roth]

The default policy for whether to handle allocations as encrypted or
shared pages is currently determined by vm_phy_pages_alloc(), which in
turn uses the policy defined by vm->memcrypt.enc_by_default.

Test programs may wish to allocate shared vaddrs for things like
sharing memory with the guest. Since enc_by_default will be true in the
case of SEV guests (since it's required in order to have the initial
ELF binary and page table become part of the initial guest payload), an
interface is needed to explicitly request shared pages.

Implement this by splitting the common code out from vm_vaddr_alloc()
and introducing a new vm_vaddr_alloc_shared().

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 .../testing/selftests/kvm/include/kvm_util.h  |  1 +
 tools/testing/selftests/kvm/lib/kvm_util.c    | 23 ++++++++++++++-----
 2 files changed, 18 insertions(+), 6 deletions(-)

diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 4bf686d664cc..d96e89ee4f40 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -143,6 +143,7 @@ void vm_mem_region_move(struct kvm_vm *vm, uint32_t slot, uint64_t new_gpa);
 void vm_mem_region_delete(struct kvm_vm *vm, uint32_t slot);
 void vm_vcpu_add(struct kvm_vm *vm, uint32_t vcpuid);
 vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min);
+vm_vaddr_t vm_vaddr_alloc_shared(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min);
 vm_vaddr_t vm_vaddr_alloc_pages(struct kvm_vm *vm, int nr_pages);
 vm_vaddr_t vm_vaddr_alloc_page(struct kvm_vm *vm);
 
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 646cffd86d09..f6df50012c8d 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -1325,14 +1325,13 @@ static vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz,
 }
 
 /*
- * VM Virtual Address Allocate
+ * VM Virtual Address Allocate Shared/Encrypted
  *
  * Input Args:
  *   vm - Virtual Machine
  *   sz - Size in bytes
  *   vaddr_min - Minimum starting virtual address
- *   data_memslot - Memory region slot for data pages
- *   pgd_memslot - Memory region slot for new virtual translation tables
+ *   encrypt - Whether the region should be handled as encrypted
  *
  * Output Args: None
  *
@@ -1345,13 +1344,15 @@ static vm_vaddr_t vm_vaddr_unused_gap(struct kvm_vm *vm, size_t sz,
  * a unique set of pages, with the minimum real allocation being at least
  * a page.
  */
-vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min)
+static vm_vaddr_t
+_vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min, bool encrypt)
 {
 	uint64_t pages = (sz >> vm->page_shift) + ((sz % vm->page_size) != 0);
 
 	virt_pgd_alloc(vm);
-	vm_paddr_t paddr = vm_phy_pages_alloc(vm, pages,
-					      KVM_UTIL_MIN_PFN * vm->page_size, 0);
+	vm_paddr_t paddr = _vm_phy_pages_alloc(vm, pages,
+					       KVM_UTIL_MIN_PFN * vm->page_size,
+					       0, encrypt);
 
 	/*
 	 * Find an unused range of virtual page addresses of at least
@@ -1372,6 +1373,16 @@ vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min)
 	return vaddr_start;
 }
 
+vm_vaddr_t vm_vaddr_alloc(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min)
+{
+	return _vm_vaddr_alloc(vm, sz, vaddr_min, vm->memcrypt.enc_by_default);
+}
+
+vm_vaddr_t vm_vaddr_alloc_shared(struct kvm_vm *vm, size_t sz, vm_vaddr_t vaddr_min)
+{
+	return _vm_vaddr_alloc(vm, sz, vaddr_min, false);
+}
+
 /*
  * VM Virtual Address Allocate Pages
  *
-- 
2.25.1

[RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Michael Roth]

Add interfaces to allow tests to create/manage SEV guests. The
additional state associated with these guests is encapsulated in a new
struct sev_vm, which is a light wrapper around struct kvm_vm. These
VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
under the covers to configure and sync up with the core kvm_util
library on what should/shouldn't be treated as encrypted memory.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/Makefile          |   1 +
 .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
 tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
 3 files changed, 366 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 5832f510a16c..c7a5e1c69e0c 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -35,6 +35,7 @@ endif
 
 LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
 LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
+LIBKVM_x86_64 += lib/x86_64/sev.c
 LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
 LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
 
diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
new file mode 100644
index 000000000000..d2f41b131ecc
--- /dev/null
+++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
@@ -0,0 +1,62 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Helpers used for SEV guests
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+#ifndef SELFTEST_KVM_SEV_H
+#define SELFTEST_KVM_SEV_H
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "kvm_util.h"
+
+#define SEV_DEV_PATH		"/dev/sev"
+#define SEV_FW_REQ_VER_MAJOR	1
+#define SEV_FW_REQ_VER_MINOR	30
+
+#define SEV_POLICY_NO_DBG	(1UL << 0)
+#define SEV_POLICY_ES		(1UL << 2)
+
+#define SEV_GUEST_ASSERT(sync, token, _cond) do {	\
+	if (!(_cond))					\
+		sev_guest_abort(sync, token, 0);	\
+} while (0)
+
+enum {
+	SEV_GSTATE_UNINIT = 0,
+	SEV_GSTATE_LUPDATE,
+	SEV_GSTATE_LSECRET,
+	SEV_GSTATE_RUNNING,
+};
+
+struct sev_sync_data {
+	uint32_t token;
+	bool pending;
+	bool done;
+	bool aborted;
+	uint64_t info;
+};
+
+struct sev_vm;
+
+void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info);
+void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info);
+void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info);
+
+void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token);
+void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token);
+
+void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data);
+struct kvm_vm *sev_get_vm(struct sev_vm *sev);
+uint8_t sev_get_enc_bit(struct sev_vm *sev);
+
+struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages);
+void sev_vm_free(struct sev_vm *sev);
+void sev_vm_launch(struct sev_vm *sev);
+void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
+void sev_vm_launch_finish(struct sev_vm *sev);
+
+#endif /* SELFTEST_KVM_SEV_H */
diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
new file mode 100644
index 000000000000..adda3b396566
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
@@ -0,0 +1,303 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Helpers used for SEV guests
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+
+#include <stdint.h>
+#include <stdbool.h>
+#include "kvm_util.h"
+#include "linux/psp-sev.h"
+#include "processor.h"
+#include "sev.h"
+
+#define PAGE_SHIFT		12
+#define PAGE_SIZE		(1UL << PAGE_SHIFT)
+
+struct sev_vm {
+	struct kvm_vm *vm;
+	int fd;
+	int enc_bit;
+	uint32_t sev_policy;
+};
+
+/* Helpers for coordinating between guests and test harness. */
+
+void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info)
+{
+	sync->token = token;
+	sync->info = info;
+	sync->pending = true;
+
+	asm volatile("hlt" : : : "memory");
+}
+
+void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
+{
+	while (true) {
+		sync->done = true;
+		sev_guest_sync(sync, token, info);
+	}
+}
+
+void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info)
+{
+	while (true) {
+		sync->aborted = true;
+		sev_guest_sync(sync, token, info);
+	}
+}
+
+void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token)
+{
+	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
+		    "unexpected exit reason: %u (%s)",
+		    run->exit_reason, exit_reason_str(run->exit_reason));
+	TEST_ASSERT(sync->token == token,
+		    "unexpected guest token, expected %d, got: %d", token,
+		    sync->token);
+	TEST_ASSERT(!sync->done, "unexpected guest state");
+	TEST_ASSERT(!sync->aborted, "unexpected guest state");
+	sync->pending = false;
+}
+
+void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
+			  uint32_t token)
+{
+	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
+		    "unexpected exit reason: %u (%s)",
+		    run->exit_reason, exit_reason_str(run->exit_reason));
+	TEST_ASSERT(sync->token == token,
+		    "unexpected guest token, expected %d, got: %d", token,
+		    sync->token);
+	TEST_ASSERT(sync->done, "unexpected guest state");
+	TEST_ASSERT(!sync->aborted, "unexpected guest state");
+	sync->pending = false;
+}
+
+/* Common SEV helpers/accessors. */
+
+struct kvm_vm *sev_get_vm(struct sev_vm *sev)
+{
+	return sev->vm;
+}
+
+uint8_t sev_get_enc_bit(struct sev_vm *sev)
+{
+	return sev->enc_bit;
+}
+
+void sev_ioctl(int sev_fd, int cmd, void *data)
+{
+	int ret;
+	struct sev_issue_cmd arg;
+
+	arg.cmd = cmd;
+	arg.data = (unsigned long)data;
+	ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg);
+	TEST_ASSERT(ret == 0,
+		    "SEV ioctl %d failed, error: %d, fw_error: %d",
+		    cmd, ret, arg.error);
+}
+
+void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
+{
+	struct kvm_sev_cmd arg = {0};
+	int ret;
+
+	arg.id = cmd;
+	arg.sev_fd = sev->fd;
+	arg.data = (__u64)data;
+
+	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_OP, &arg);
+	TEST_ASSERT(ret == 0,
+		    "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d",
+		    cmd, ret, errno, strerror(errno), arg.error);
+}
+
+/* Local helpers. */
+
+static void
+sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)
+{
+	struct kvm_enc_region range = {0};
+	int ret;
+
+	pr_debug("register_user_range: hva: %p, size: %lu\n", hva, size);
+
+	range.addr = (__u64)hva;
+	range.size = size;
+
+	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_REG_REGION, &range);
+	TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno);
+}
+
+static void
+sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
+{
+	struct kvm_sev_launch_update_data ksev_update_data = {0};
+
+	pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
+
+	ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
+	ksev_update_data.len = size;
+
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
+}
+
+static void sev_encrypt(struct sev_vm *sev)
+{
+	struct sparsebit *enc_phy_pages;
+	struct kvm_vm *vm = sev->vm;
+	sparsebit_idx_t pg = 0;
+	vm_paddr_t gpa_start;
+	uint64_t memory_size;
+
+	/* Only memslot 0 supported for now. */
+	enc_phy_pages = vm_get_encrypted_phy_pages(sev->vm, 0, &gpa_start, &memory_size);
+	TEST_ASSERT(enc_phy_pages, "Unable to retrieve encrypted pages bitmap");
+	while (pg < (memory_size / vm_get_page_size(vm))) {
+		sparsebit_idx_t pg_cnt;
+
+		if (sparsebit_is_clear(enc_phy_pages, pg)) {
+			pg = sparsebit_next_set(enc_phy_pages, pg);
+			if (!pg)
+				break;
+		}
+
+		pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg;
+		if (pg_cnt <= 0)
+			pg_cnt = 1;
+
+		sev_encrypt_phy_range(sev,
+				      gpa_start + pg * vm_get_page_size(vm),
+				      pg_cnt * vm_get_page_size(vm));
+		pg += pg_cnt;
+	}
+
+	sparsebit_free(&enc_phy_pages);
+}
+
+/* SEV VM implementation. */
+
+static struct sev_vm *sev_common_create(struct kvm_vm *vm)
+{
+	struct sev_user_data_status sev_status = {0};
+	uint32_t eax, ebx, ecx, edx;
+	struct sev_vm *sev;
+	int sev_fd;
+
+	sev_fd = open(SEV_DEV_PATH, O_RDWR);
+	if (sev_fd < 0) {
+		pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n",
+			SEV_DEV_PATH, sev_fd);
+		return NULL;
+	}
+
+	sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status);
+
+	if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR ||
+	      (sev_status.api_major == SEV_FW_REQ_VER_MAJOR &&
+	       sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) {
+		pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n",
+			sev_status.api_major, sev_status.api_minor, sev_status.build,
+			SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR);
+		return NULL;
+	}
+
+	sev = calloc(1, sizeof(*sev));
+	sev->fd = sev_fd;
+	sev->vm = vm;
+
+	/* Get encryption bit via CPUID. */
+	eax = 0x8000001f;
+	ecx = 0;
+	cpuid(&eax, &ebx, &ecx, &edx);
+	sev->enc_bit = ebx & 0x3F;
+
+	return sev;
+}
+
+static void sev_common_free(struct sev_vm *sev)
+{
+	close(sev->fd);
+	free(sev);
+}
+
+struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
+{
+	struct sev_vm *sev;
+	struct kvm_vm *vm;
+
+	/* Need to handle memslots after init, and after setting memcrypt. */
+	vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
+	sev = sev_common_create(vm);
+	if (!sev)
+		return NULL;
+	sev->sev_policy = policy;
+
+	kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
+
+	vm_set_memory_encryption(vm, true, true, sev->enc_bit);
+	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
+	sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
+
+	pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
+		sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
+
+	return sev;
+}
+
+void sev_vm_free(struct sev_vm *sev)
+{
+	kvm_vm_free(sev->vm);
+	sev_common_free(sev);
+}
+
+void sev_vm_launch(struct sev_vm *sev)
+{
+	struct kvm_sev_launch_start ksev_launch_start = {0};
+	struct kvm_sev_guest_status ksev_status = {0};
+
+	ksev_launch_start.policy = sev->sev_policy;
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start);
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
+	TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy.");
+	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE,
+		    "Unexpected guest state: %d", ksev_status.state);
+
+	sev_encrypt(sev);
+}
+
+void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
+{
+	struct kvm_sev_launch_measure ksev_launch_measure = {0};
+	struct kvm_sev_guest_status ksev_guest_status = {0};
+
+	ksev_launch_measure.len = 256;
+	ksev_launch_measure.uaddr = (__u64)measurement;
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure);
+
+	/* Measurement causes a state transition, check that. */
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status);
+	TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET,
+		    "Unexpected guest state: %d", ksev_guest_status.state);
+}
+
+void sev_vm_launch_finish(struct sev_vm *sev)
+{
+	struct kvm_sev_guest_status ksev_status = {0};
+
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
+	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE ||
+		    ksev_status.state == SEV_GSTATE_LSECRET,
+		    "Unexpected guest state: %d", ksev_status.state);
+
+	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL);
+
+	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
+	TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
+		    "Unexpected guest state: %d", ksev_status.state);
+}
-- 
2.25.1

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Marc Orr]

On Wed, Oct 6, 2021 at 1:40 PM Michael Roth <michael.roth@amd.com> wrote:
>
> Add interfaces to allow tests to create/manage SEV guests. The
> additional state associated with these guests is encapsulated in a new
> struct sev_vm, which is a light wrapper around struct kvm_vm. These
> VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
> under the covers to configure and sync up with the core kvm_util
> library on what should/shouldn't be treated as encrypted memory.
>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>  tools/testing/selftests/kvm/Makefile          |   1 +
>  .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
>  tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
>  3 files changed, 366 insertions(+)
>  create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
>  create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
>
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index 5832f510a16c..c7a5e1c69e0c 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -35,6 +35,7 @@ endif
>
>  LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
>  LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
> +LIBKVM_x86_64 += lib/x86_64/sev.c

Regarding RFC-level feedback: First off, I'm super jazzed with what
I'm seeing so far! (While this is my first review, I've been studying
the patches up through the SEV boot test, i.e., patch #7). One thing
I'm wondering is: the way this is structured is to essentially split
the test cases into non-SEV and SEV. I'm wondering how hard it would
be to add some flag or environment variable to set up pre-existing
tests to run under SEV. Or is this something you all thought about,
and decided that it does not make sense?

Looking at how the guest memory is handled, it seems like it's not far
off from handling SEV transparently across all test cases. I'd think
that we could just default all memory to use the encryption bit, and
then have test cases, such as the test case in patch #7, clear the
encryption bit for shared pages. However, I think the VM creation
would need a bit more refactoring to work with other test cases.

>  LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
>  LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
>
> diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
> new file mode 100644
> index 000000000000..d2f41b131ecc
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
> @@ -0,0 +1,62 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Helpers used for SEV guests
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +#ifndef SELFTEST_KVM_SEV_H
> +#define SELFTEST_KVM_SEV_H
> +
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include "kvm_util.h"
> +
> +#define SEV_DEV_PATH           "/dev/sev"

Not necessary for the initial patches, but eventually, it would be
nice to make this configurable. On the machine I was using to test
this, the sev device appears at `/mnt/devtmpfs/sev`

> +#define SEV_FW_REQ_VER_MAJOR   1
> +#define SEV_FW_REQ_VER_MINOR   30

Where does the requirement for this minimum version come from? Maybe
add a comment?

Edit: Is this for patches later on in the series that exercise SNP? If
so, I think it would be better to add a check like this in the test
itself, rather than globally. I happened to test this on a machine
with a very old PSP FW, 0.22, and the SEV test added in patch #7 seems
to work fine with this ancient PSP FW.

> +
> +#define SEV_POLICY_NO_DBG      (1UL << 0)
> +#define SEV_POLICY_ES          (1UL << 2)
> +
> +#define SEV_GUEST_ASSERT(sync, token, _cond) do {      \
> +       if (!(_cond))                                   \
> +               sev_guest_abort(sync, token, 0);        \
> +} while (0)
> +
> +enum {
> +       SEV_GSTATE_UNINIT = 0,
> +       SEV_GSTATE_LUPDATE,
> +       SEV_GSTATE_LSECRET,
> +       SEV_GSTATE_RUNNING,
> +};
> +
> +struct sev_sync_data {
> +       uint32_t token;
> +       bool pending;
> +       bool done;
> +       bool aborted;
> +       uint64_t info;
> +};

nit: This struct could use some comments. For example, `token` is not
totally self-explanatory. In general, a comment explaining how this
struct is intended to be used by test cases seems useful.

> +
> +struct sev_vm;
> +
> +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +
> +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> +                         uint32_t token);
> +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> +                         uint32_t token);
> +
> +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data);
> +struct kvm_vm *sev_get_vm(struct sev_vm *sev);
> +uint8_t sev_get_enc_bit(struct sev_vm *sev);
> +
> +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages);
> +void sev_vm_free(struct sev_vm *sev);
> +void sev_vm_launch(struct sev_vm *sev);
> +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
> +void sev_vm_launch_finish(struct sev_vm *sev);
> +
> +#endif /* SELFTEST_KVM_SEV_H */
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> new file mode 100644
> index 000000000000..adda3b396566
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> @@ -0,0 +1,303 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Helpers used for SEV guests
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include "kvm_util.h"
> +#include "linux/psp-sev.h"
> +#include "processor.h"
> +#include "sev.h"
> +
> +#define PAGE_SHIFT             12
> +#define PAGE_SIZE              (1UL << PAGE_SHIFT)
> +
> +struct sev_vm {
> +       struct kvm_vm *vm;
> +       int fd;
> +       int enc_bit;
> +       uint32_t sev_policy;
> +};
> +
> +/* Helpers for coordinating between guests and test harness. */
> +
> +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +       sync->token = token;
> +       sync->info = info;
> +       sync->pending = true;
> +
> +       asm volatile("hlt" : : : "memory");
> +}
> +
> +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +       while (true) {
> +               sync->done = true;
> +               sev_guest_sync(sync, token, info);
> +       }
> +}
> +
> +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +       while (true) {
> +               sync->aborted = true;
> +               sev_guest_sync(sync, token, info);
> +       }
> +}

Maybe this should have some logic to make sure it only gets executed
once instead of a while loop. Something like:

void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
{
     static bool abort = false;

     SEV_GUEST_ASSERT(sync, 0xDEADBEEF, !abort);
     abort = true;

     sync->done = true;
     sev_guest_sync(sync, token, info);
}

> +
> +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> +                         uint32_t token)
> +{
> +       TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> +                   "unexpected exit reason: %u (%s)",
> +                   run->exit_reason, exit_reason_str(run->exit_reason));
> +       TEST_ASSERT(sync->token == token,
> +                   "unexpected guest token, expected %d, got: %d", token,
> +                   sync->token);
> +       TEST_ASSERT(!sync->done, "unexpected guest state");
> +       TEST_ASSERT(!sync->aborted, "unexpected guest state");
> +       sync->pending = false;

Check that `pending` is `true` before setting to `false`?

> +}
> +
> +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> +                         uint32_t token)
> +{
> +       TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> +                   "unexpected exit reason: %u (%s)",
> +                   run->exit_reason, exit_reason_str(run->exit_reason));
> +       TEST_ASSERT(sync->token == token,
> +                   "unexpected guest token, expected %d, got: %d", token,
> +                   sync->token);
> +       TEST_ASSERT(sync->done, "unexpected guest state");
> +       TEST_ASSERT(!sync->aborted, "unexpected guest state");
> +       sync->pending = false;
> +}

nit: This function is nearly identical to `sev_check_guest_sync()`,
other than the ASSERT for `sync->done`. Might be worth splitting out a
common static helper or using a single function for both cases, and
distinguishing between them with a function parameter.

> +
> +/* Common SEV helpers/accessors. */
> +
> +struct kvm_vm *sev_get_vm(struct sev_vm *sev)
> +{
> +       return sev->vm;
> +}
> +
> +uint8_t sev_get_enc_bit(struct sev_vm *sev)
> +{
> +       return sev->enc_bit;
> +}
> +
> +void sev_ioctl(int sev_fd, int cmd, void *data)
> +{
> +       int ret;
> +       struct sev_issue_cmd arg;
> +
> +       arg.cmd = cmd;
> +       arg.data = (unsigned long)data;

nit: Should the cast be `(__u64)`, rather than `(unsigned long)`? This
is how `data` is defined in `struct sev_issue_cmd`, and also how the
`data` field is cast in `sev_ioctl`, below.

> +       ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg);
> +       TEST_ASSERT(ret == 0,
> +                   "SEV ioctl %d failed, error: %d, fw_error: %d",
> +                   cmd, ret, arg.error);
> +}
> +
> +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
> +{
> +       struct kvm_sev_cmd arg = {0};
> +       int ret;
> +
> +       arg.id = cmd;
> +       arg.sev_fd = sev->fd;
> +       arg.data = (__u64)data;
> +
> +       ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_OP, &arg);
> +       TEST_ASSERT(ret == 0,
> +                   "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d",
> +                   cmd, ret, errno, strerror(errno), arg.error);

nit: Technically, the `KVM_MEMORY_ENCRYPT_OP ` ioctl failed. The
failure message should reflect this. Maybe something like:

"SEV KVM_MEMORY_ENCRYPT_OP ioctl w/ cmd: %d failed, ..."

> +}
> +
> +/* Local helpers. */
> +
> +static void
> +sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)
> +{
> +       struct kvm_enc_region range = {0};
> +       int ret;
> +
> +       pr_debug("register_user_range: hva: %p, size: %lu\n", hva, size);
> +
> +       range.addr = (__u64)hva;
> +       range.size = size;
> +
> +       ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_REG_REGION, &range);
> +       TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno);
> +}

I don't see any code to call `KVM_MEMORY_ENCRYPT_UNREG_REGION` in this
code. Shouldn't we be calling it to unpin the memory when the test is
done?

> +
> +static void
> +sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
> +{
> +       struct kvm_sev_launch_update_data ksev_update_data = {0};
> +
> +       pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
> +
> +       ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
> +       ksev_update_data.len = size;
> +
> +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
> +}
> +
> +static void sev_encrypt(struct sev_vm *sev)
> +{
> +       struct sparsebit *enc_phy_pages;
> +       struct kvm_vm *vm = sev->vm;
> +       sparsebit_idx_t pg = 0;
> +       vm_paddr_t gpa_start;
> +       uint64_t memory_size;
> +
> +       /* Only memslot 0 supported for now. */
> +       enc_phy_pages = vm_get_encrypted_phy_pages(sev->vm, 0, &gpa_start, &memory_size);
> +       TEST_ASSERT(enc_phy_pages, "Unable to retrieve encrypted pages bitmap");
> +       while (pg < (memory_size / vm_get_page_size(vm))) {
> +               sparsebit_idx_t pg_cnt;
> +
> +               if (sparsebit_is_clear(enc_phy_pages, pg)) {
> +                       pg = sparsebit_next_set(enc_phy_pages, pg);
> +                       if (!pg)
> +                               break;
> +               }
> +
> +               pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg;
> +               if (pg_cnt <= 0)
> +                       pg_cnt = 1;

The `pg_cnt <= 0` case doesn't seem correct. First off, I'd just git
rid of the `<`, because `pg_cnt` is unsigned. Second, the comment
header for `sparsebit_next_clear()` says that a return value of `0`
indicates that no bits following `prev` are cleared. Thus, in this
case, I'd think that `pg_cnt` should be set to `memory_size - pg`. So
maybe something like:

end = sparsebit_next_clear(enc_phy_pages, pg);
if (end == 0)
     end = memory_size;
pg_cnt = end - pg;

> +
> +               sev_encrypt_phy_range(sev,
> +                                     gpa_start + pg * vm_get_page_size(vm),
> +                                     pg_cnt * vm_get_page_size(vm));
> +               pg += pg_cnt;
> +       }
> +
> +       sparsebit_free(&enc_phy_pages);
> +}
> +
> +/* SEV VM implementation. */
> +
> +static struct sev_vm *sev_common_create(struct kvm_vm *vm)
> +{
> +       struct sev_user_data_status sev_status = {0};
> +       uint32_t eax, ebx, ecx, edx;
> +       struct sev_vm *sev;
> +       int sev_fd;
> +
> +       sev_fd = open(SEV_DEV_PATH, O_RDWR);
> +       if (sev_fd < 0) {
> +               pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n",
> +                       SEV_DEV_PATH, sev_fd);
> +               return NULL;
> +       }
> +
> +       sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status);
> +
> +       if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR ||
> +             (sev_status.api_major == SEV_FW_REQ_VER_MAJOR &&
> +              sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) {
> +               pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n",
> +                       sev_status.api_major, sev_status.api_minor, sev_status.build,
> +                       SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR);

nit: If we fail here, we leak `sev_fd`. Should we call `close(sev_fd)` here?

> +               return NULL;
> +       }
> +
> +       sev = calloc(1, sizeof(*sev));
> +       sev->fd = sev_fd;
> +       sev->vm = vm;
> +
> +       /* Get encryption bit via CPUID. */
> +       eax = 0x8000001f;
> +       ecx = 0;
> +       cpuid(&eax, &ebx, &ecx, &edx);
> +       sev->enc_bit = ebx & 0x3F;
> +
> +       return sev;
> +}
> +
> +static void sev_common_free(struct sev_vm *sev)
> +{
> +       close(sev->fd);
> +       free(sev);
> +}
> +
> +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
> +{
> +       struct sev_vm *sev;
> +       struct kvm_vm *vm;
> +
> +       /* Need to handle memslots after init, and after setting memcrypt. */
> +       vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
> +       sev = sev_common_create(vm);
> +       if (!sev)
> +               return NULL;
> +       sev->sev_policy = policy;
> +
> +       kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
> +
> +       vm_set_memory_encryption(vm, true, true, sev->enc_bit);
> +       vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
> +       sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
> +
> +       pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
> +               sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
> +
> +       return sev;
> +}
> +
> +void sev_vm_free(struct sev_vm *sev)
> +{
> +       kvm_vm_free(sev->vm);
> +       sev_common_free(sev);
> +}
> +
> +void sev_vm_launch(struct sev_vm *sev)
> +{
> +       struct kvm_sev_launch_start ksev_launch_start = {0};
> +       struct kvm_sev_guest_status ksev_status = {0};
> +
> +       ksev_launch_start.policy = sev->sev_policy;
> +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start);
> +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +       TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy.");
> +       TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE,
> +                   "Unexpected guest state: %d", ksev_status.state);
> +
> +       sev_encrypt(sev);
> +}
> +
> +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
> +{
> +       struct kvm_sev_launch_measure ksev_launch_measure = {0};
> +       struct kvm_sev_guest_status ksev_guest_status = {0};
> +
> +       ksev_launch_measure.len = 256;
> +       ksev_launch_measure.uaddr = (__u64)measurement;
> +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure);
> +
> +       /* Measurement causes a state transition, check that. */
> +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status);
> +       TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET,
> +                   "Unexpected guest state: %d", ksev_guest_status.state);
> +}
> +
> +void sev_vm_launch_finish(struct sev_vm *sev)
> +{
> +       struct kvm_sev_guest_status ksev_status = {0};
> +
> +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +       TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE ||
> +                   ksev_status.state == SEV_GSTATE_LSECRET,
> +                   "Unexpected guest state: %d", ksev_status.state);
> +
> +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL);
> +
> +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +       TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
> +                   "Unexpected guest state: %d", ksev_status.state);
> +}
> --
> 2.25.1
>

This is phenomenal. I'll try to send feedback on the other patches in
the first batch of 7 sooner rather than later. I haven't looked past
patch #7 yet. Let me know what you think about my first comment, on
whether we can get all pre-existing tests to run under SEV, or that's
a bad idea. I probably haven't given it as much thought as you have.

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Michael Roth]

On Sun, Oct 10, 2021 at 08:17:00PM -0700, Marc Orr wrote:
> On Wed, Oct 6, 2021 at 1:40 PM Michael Roth <michael.roth@amd.com> wrote:
> >
> > Add interfaces to allow tests to create/manage SEV guests. The
> > additional state associated with these guests is encapsulated in a new
> > struct sev_vm, which is a light wrapper around struct kvm_vm. These
> > VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
> > under the covers to configure and sync up with the core kvm_util
> > library on what should/shouldn't be treated as encrypted memory.
> >
> > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > ---
> >  tools/testing/selftests/kvm/Makefile          |   1 +
> >  .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
> >  tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
> >  3 files changed, 366 insertions(+)
> >  create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
> >  create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
> >
> > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> > index 5832f510a16c..c7a5e1c69e0c 100644
> > --- a/tools/testing/selftests/kvm/Makefile
> > +++ b/tools/testing/selftests/kvm/Makefile
> > @@ -35,6 +35,7 @@ endif
> >
> >  LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
> >  LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
> > +LIBKVM_x86_64 += lib/x86_64/sev.c
> 
> Regarding RFC-level feedback: First off, I'm super jazzed with what
> I'm seeing so far! (While this is my first review, I've been studying
> the patches up through the SEV boot test, i.e., patch #7). One thing
> I'm wondering is: the way this is structured is to essentially split
> the test cases into non-SEV and SEV. I'm wondering how hard it would
> be to add some flag or environment variable to set up pre-existing
> tests to run under SEV. Or is this something you all thought about,
> and decided that it does not make sense?
> 
> Looking at how the guest memory is handled, it seems like it's not far
> off from handling SEV transparently across all test cases. I'd think
> that we could just default all memory to use the encryption bit, and
> then have test cases, such as the test case in patch #7, clear the
> encryption bit for shared pages. However, I think the VM creation
> would need a bit more refactoring to work with other test cases.

I think it's possible, but there's a few missing pieces:

1) As you indicated, existing tests which rely on vm_create(),
   vm_create_default(), vm_create_default_with_vcpus(), etc. would either
   need to be updated with whatever new interface provides this 'use-sev'
   flag, or it would need to happen underneath the covers based on said
   environment variable/global/etc. There's also the question of where
   to hook in the sev_vm_launch_start() hooks. Maybe the first time a
   vcpu_run() is issued? Or maybe some explict call each test will need
   to be updated to call just prior to initial execution.

2) Many of the existing tests use the GUESY_SYNC/ucall stuff to handle
   synchronization between host userspace and guest kernel, which relies on
   guests issuing PIO instructions to particular port addresses to cause an
   exit back to host userspace, with various parameters passed via register
   arguments.

   - For SEV this would almost work as-is, but some tests might rely on
     things like memory addresses being passed in this way so would need
     to audit the code and mark that memory as shared where needed.

   - For SEV-ES/SEV-SNP, there's a bit more work since:

     - The registers will not be accessible through the existing
       KVM_GET_REGS mechanism. It may be possible to set some flag/hook to
       set/access arguments through some other mechanism like a shared
       buffer for certain VM types though.

     - Additionally, the #VC handler only supports CPUID currently, and
       leverages that fact to avoid doing any significant instruction
       decoding. Instead the SEV tests use HLT instructions to handle exits
       to host userspace, which may not work for some tests. So unless
       there's some other mechanism that SEV/non-SEV tests could utilize
       rather that PIO, the #VC handler would need to support PIO, which
       would be nice to have either way, but would likely involve
       pulling in the intruction decoder library used in the kernel, or
       some subset/re-implementation of it at least.

3) Similar to SEV-ES/SEV-SNP requirements for 1), tests which generate
   PIO/MMIO and other NAE events would need appropriate support for those
   events in the #VC handler. Nice-to-have either way, but not sure atm
   how much it would be to implement all of that. Also any tests relying
   on things like KVM_GET_REGS/KVM_GET_SREGS are non-starters.

Maybe with 1) and 2) in place, some tests can start incrementally being
'whitelisted' to run under SEV without needing to support anything and
everything right off the bat. Might also be good to see how the TDX stuff
settles since there may be similar considerations there as well.

> 
> >  LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
> >  LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
> >
> > diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
> > new file mode 100644
> > index 000000000000..d2f41b131ecc
> > --- /dev/null
> > +++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
> > @@ -0,0 +1,62 @@
> > +/* SPDX-License-Identifier: GPL-2.0-only */
> > +/*
> > + * Helpers used for SEV guests
> > + *
> > + * Copyright (C) 2021 Advanced Micro Devices
> > + */
> > +#ifndef SELFTEST_KVM_SEV_H
> > +#define SELFTEST_KVM_SEV_H
> > +
> > +#include <stdint.h>
> > +#include <stdbool.h>
> > +#include "kvm_util.h"
> > +
> > +#define SEV_DEV_PATH           "/dev/sev"
> 
> Not necessary for the initial patches, but eventually, it would be
> nice to make this configurable. On the machine I was using to test
> this, the sev device appears at `/mnt/devtmpfs/sev`

Hmm, don't see any use of getenv() currently, so I guess maybe a
compile-time option would be the preferred approach. I'll take a look at
that.

> 
> > +#define SEV_FW_REQ_VER_MAJOR   1
> > +#define SEV_FW_REQ_VER_MINOR   30
> 
> Where does the requirement for this minimum version come from? Maybe
> add a comment?
> 
> Edit: Is this for patches later on in the series that exercise SNP? If
> so, I think it would be better to add a check like this in the test
> itself, rather than globally. I happened to test this on a machine
> with a very old PSP FW, 0.22, and the SEV test added in patch #7 seems
> to work fine with this ancient PSP FW.

Ah, yes, this was mostly for SNP support. I'll implement a separate minimum
version for SEV/SEV-ES.

> 
> > +
> > +#define SEV_POLICY_NO_DBG      (1UL << 0)
> > +#define SEV_POLICY_ES          (1UL << 2)
> > +
> > +#define SEV_GUEST_ASSERT(sync, token, _cond) do {      \
> > +       if (!(_cond))                                   \
> > +               sev_guest_abort(sync, token, 0);        \
> > +} while (0)
> > +
> > +enum {
> > +       SEV_GSTATE_UNINIT = 0,
> > +       SEV_GSTATE_LUPDATE,
> > +       SEV_GSTATE_LSECRET,
> > +       SEV_GSTATE_RUNNING,
> > +};
> > +
> > +struct sev_sync_data {
> > +       uint32_t token;
> > +       bool pending;
> > +       bool done;
> > +       bool aborted;
> > +       uint64_t info;
> > +};
> 
> nit: This struct could use some comments. For example, `token` is not
> totally self-explanatory. In general, a comment explaining how this
> struct is intended to be used by test cases seems useful.

Will do.

> 
> > +
> > +struct sev_vm;
> > +
> > +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> > +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> > +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> > +
> > +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> > +                         uint32_t token);
> > +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> > +                         uint32_t token);
> > +
> > +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data);
> > +struct kvm_vm *sev_get_vm(struct sev_vm *sev);
> > +uint8_t sev_get_enc_bit(struct sev_vm *sev);
> > +
> > +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages);
> > +void sev_vm_free(struct sev_vm *sev);
> > +void sev_vm_launch(struct sev_vm *sev);
> > +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
> > +void sev_vm_launch_finish(struct sev_vm *sev);
> > +
> > +#endif /* SELFTEST_KVM_SEV_H */
> > diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> > new file mode 100644
> > index 000000000000..adda3b396566
> > --- /dev/null
> > +++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> > @@ -0,0 +1,303 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Helpers used for SEV guests
> > + *
> > + * Copyright (C) 2021 Advanced Micro Devices
> > + */
> > +
> > +#include <stdint.h>
> > +#include <stdbool.h>
> > +#include "kvm_util.h"
> > +#include "linux/psp-sev.h"
> > +#include "processor.h"
> > +#include "sev.h"
> > +
> > +#define PAGE_SHIFT             12
> > +#define PAGE_SIZE              (1UL << PAGE_SHIFT)
> > +
> > +struct sev_vm {
> > +       struct kvm_vm *vm;
> > +       int fd;
> > +       int enc_bit;
> > +       uint32_t sev_policy;
> > +};
> > +
> > +/* Helpers for coordinating between guests and test harness. */
> > +
> > +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> > +{
> > +       sync->token = token;
> > +       sync->info = info;
> > +       sync->pending = true;
> > +
> > +       asm volatile("hlt" : : : "memory");
> > +}
> > +
> > +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> > +{
> > +       while (true) {
> > +               sync->done = true;
> > +               sev_guest_sync(sync, token, info);
> > +       }
> > +}
> > +
> > +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> > +{
> > +       while (true) {
> > +               sync->aborted = true;
> > +               sev_guest_sync(sync, token, info);
> > +       }
> > +}
> 
> Maybe this should have some logic to make sure it only gets executed
> once instead of a while loop. Something like:
> 
> void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> {
>      static bool abort = false;
> 
>      SEV_GUEST_ASSERT(sync, 0xDEADBEEF, !abort);
>      abort = true;
> 
>      sync->done = true;
>      sev_guest_sync(sync, token, info);
> }

That makes sense.

> 
> > +
> > +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> > +                         uint32_t token)
> > +{
> > +       TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> > +                   "unexpected exit reason: %u (%s)",
> > +                   run->exit_reason, exit_reason_str(run->exit_reason));
> > +       TEST_ASSERT(sync->token == token,
> > +                   "unexpected guest token, expected %d, got: %d", token,
> > +                   sync->token);
> > +       TEST_ASSERT(!sync->done, "unexpected guest state");
> > +       TEST_ASSERT(!sync->aborted, "unexpected guest state");
> > +       sync->pending = false;
> 
> Check that `pending` is `true` before setting to `false`?

Yes, that should be the case.

> 
> > +}
> > +
> > +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> > +                         uint32_t token)
> > +{
> > +       TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> > +                   "unexpected exit reason: %u (%s)",
> > +                   run->exit_reason, exit_reason_str(run->exit_reason));
> > +       TEST_ASSERT(sync->token == token,
> > +                   "unexpected guest token, expected %d, got: %d", token,
> > +                   sync->token);
> > +       TEST_ASSERT(sync->done, "unexpected guest state");
> > +       TEST_ASSERT(!sync->aborted, "unexpected guest state");
> > +       sync->pending = false;
> > +}
> 
> nit: This function is nearly identical to `sev_check_guest_sync()`,
> other than the ASSERT for `sync->done`. Might be worth splitting out a
> common static helper or using a single function for both cases, and
> distinguishing between them with a function parameter.

Will do.

> 
> > +
> > +/* Common SEV helpers/accessors. */
> > +
> > +struct kvm_vm *sev_get_vm(struct sev_vm *sev)
> > +{
> > +       return sev->vm;
> > +}
> > +
> > +uint8_t sev_get_enc_bit(struct sev_vm *sev)
> > +{
> > +       return sev->enc_bit;
> > +}
> > +
> > +void sev_ioctl(int sev_fd, int cmd, void *data)
> > +{
> > +       int ret;
> > +       struct sev_issue_cmd arg;
> > +
> > +       arg.cmd = cmd;
> > +       arg.data = (unsigned long)data;
> 
> nit: Should the cast be `(__u64)`, rather than `(unsigned long)`? This
> is how `data` is defined in `struct sev_issue_cmd`, and also how the
> `data` field is cast in `sev_ioctl`, below.
> 
> > +       ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg);
> > +       TEST_ASSERT(ret == 0,
> > +                   "SEV ioctl %d failed, error: %d, fw_error: %d",
> > +                   cmd, ret, arg.error);
> > +}
> > +
> > +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
> > +{
> > +       struct kvm_sev_cmd arg = {0};
> > +       int ret;
> > +
> > +       arg.id = cmd;
> > +       arg.sev_fd = sev->fd;
> > +       arg.data = (__u64)data;
> > +
> > +       ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_OP, &arg);
> > +       TEST_ASSERT(ret == 0,
> > +                   "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d",
> > +                   cmd, ret, errno, strerror(errno), arg.error);
> 
> nit: Technically, the `KVM_MEMORY_ENCRYPT_OP ` ioctl failed. The
> failure message should reflect this. Maybe something like:
> 
> "SEV KVM_MEMORY_ENCRYPT_OP ioctl w/ cmd: %d failed, ..."
> 
> > +}
> > +
> > +/* Local helpers. */
> > +
> > +static void
> > +sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)
> > +{
> > +       struct kvm_enc_region range = {0};
> > +       int ret;
> > +
> > +       pr_debug("register_user_range: hva: %p, size: %lu\n", hva, size);
> > +
> > +       range.addr = (__u64)hva;
> > +       range.size = size;
> > +
> > +       ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_REG_REGION, &range);
> > +       TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno);
> > +}
> 
> I don't see any code to call `KVM_MEMORY_ENCRYPT_UNREG_REGION` in this
> code. Shouldn't we be calling it to unpin the memory when the test is
> done?

Yes, I should probably do that in sev_vm_free() for the main memslot at
least.

> 
> > +
> > +static void
> > +sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
> > +{
> > +       struct kvm_sev_launch_update_data ksev_update_data = {0};
> > +
> > +       pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
> > +
> > +       ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
> > +       ksev_update_data.len = size;
> > +
> > +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
> > +}
> > +
> > +static void sev_encrypt(struct sev_vm *sev)
> > +{
> > +       struct sparsebit *enc_phy_pages;
> > +       struct kvm_vm *vm = sev->vm;
> > +       sparsebit_idx_t pg = 0;
> > +       vm_paddr_t gpa_start;
> > +       uint64_t memory_size;
> > +
> > +       /* Only memslot 0 supported for now. */
> > +       enc_phy_pages = vm_get_encrypted_phy_pages(sev->vm, 0, &gpa_start, &memory_size);
> > +       TEST_ASSERT(enc_phy_pages, "Unable to retrieve encrypted pages bitmap");
> > +       while (pg < (memory_size / vm_get_page_size(vm))) {
> > +               sparsebit_idx_t pg_cnt;
> > +
> > +               if (sparsebit_is_clear(enc_phy_pages, pg)) {
> > +                       pg = sparsebit_next_set(enc_phy_pages, pg);
> > +                       if (!pg)
> > +                               break;
> > +               }
> > +
> > +               pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg;
> > +               if (pg_cnt <= 0)
> > +                       pg_cnt = 1;
> 
> The `pg_cnt <= 0` case doesn't seem correct. First off, I'd just git
> rid of the `<`, because `pg_cnt` is unsigned. Second, the comment
> header for `sparsebit_next_clear()` says that a return value of `0`
> indicates that no bits following `prev` are cleared. Thus, in this
> case, I'd think that `pg_cnt` should be set to `memory_size - pg`. So
> maybe something like:

Ah, yes I think I was assuming I'd only hit the pg_cnt <= 0 case if I
was looking at the last page, but it could also be hit for any number of
contiguous pages at the end of the bitmap.

> 
> end = sparsebit_next_clear(enc_phy_pages, pg);
> if (end == 0)
>      end = memory_size;
> pg_cnt = end - pg;

That should do the trick, thanks!

> 
> > +
> > +               sev_encrypt_phy_range(sev,
> > +                                     gpa_start + pg * vm_get_page_size(vm),
> > +                                     pg_cnt * vm_get_page_size(vm));
> > +               pg += pg_cnt;
> > +       }
> > +
> > +       sparsebit_free(&enc_phy_pages);
> > +}
> > +
> > +/* SEV VM implementation. */
> > +
> > +static struct sev_vm *sev_common_create(struct kvm_vm *vm)
> > +{
> > +       struct sev_user_data_status sev_status = {0};
> > +       uint32_t eax, ebx, ecx, edx;
> > +       struct sev_vm *sev;
> > +       int sev_fd;
> > +
> > +       sev_fd = open(SEV_DEV_PATH, O_RDWR);
> > +       if (sev_fd < 0) {
> > +               pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n",
> > +                       SEV_DEV_PATH, sev_fd);
> > +               return NULL;
> > +       }
> > +
> > +       sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status);
> > +
> > +       if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR ||
> > +             (sev_status.api_major == SEV_FW_REQ_VER_MAJOR &&
> > +              sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) {
> > +               pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n",
> > +                       sev_status.api_major, sev_status.api_minor, sev_status.build,
> > +                       SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR);
> 
> nit: If we fail here, we leak `sev_fd`. Should we call `close(sev_fd)` here?
> 
> > +               return NULL;
> > +       }
> > +
> > +       sev = calloc(1, sizeof(*sev));
> > +       sev->fd = sev_fd;
> > +       sev->vm = vm;
> > +
> > +       /* Get encryption bit via CPUID. */
> > +       eax = 0x8000001f;
> > +       ecx = 0;
> > +       cpuid(&eax, &ebx, &ecx, &edx);
> > +       sev->enc_bit = ebx & 0x3F;
> > +
> > +       return sev;
> > +}
> > +
> > +static void sev_common_free(struct sev_vm *sev)
> > +{
> > +       close(sev->fd);
> > +       free(sev);
> > +}
> > +
> > +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
> > +{
> > +       struct sev_vm *sev;
> > +       struct kvm_vm *vm;
> > +
> > +       /* Need to handle memslots after init, and after setting memcrypt. */
> > +       vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
> > +       sev = sev_common_create(vm);
> > +       if (!sev)
> > +               return NULL;
> > +       sev->sev_policy = policy;
> > +
> > +       kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
> > +
> > +       vm_set_memory_encryption(vm, true, true, sev->enc_bit);
> > +       vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
> > +       sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
> > +
> > +       pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
> > +               sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
> > +
> > +       return sev;
> > +}
> > +
> > +void sev_vm_free(struct sev_vm *sev)
> > +{
> > +       kvm_vm_free(sev->vm);
> > +       sev_common_free(sev);
> > +}
> > +
> > +void sev_vm_launch(struct sev_vm *sev)
> > +{
> > +       struct kvm_sev_launch_start ksev_launch_start = {0};
> > +       struct kvm_sev_guest_status ksev_status = {0};
> > +
> > +       ksev_launch_start.policy = sev->sev_policy;
> > +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start);
> > +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> > +       TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy.");
> > +       TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE,
> > +                   "Unexpected guest state: %d", ksev_status.state);
> > +
> > +       sev_encrypt(sev);
> > +}
> > +
> > +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
> > +{
> > +       struct kvm_sev_launch_measure ksev_launch_measure = {0};
> > +       struct kvm_sev_guest_status ksev_guest_status = {0};
> > +
> > +       ksev_launch_measure.len = 256;
> > +       ksev_launch_measure.uaddr = (__u64)measurement;
> > +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure);
> > +
> > +       /* Measurement causes a state transition, check that. */
> > +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status);
> > +       TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET,
> > +                   "Unexpected guest state: %d", ksev_guest_status.state);
> > +}
> > +
> > +void sev_vm_launch_finish(struct sev_vm *sev)
> > +{
> > +       struct kvm_sev_guest_status ksev_status = {0};
> > +
> > +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> > +       TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE ||
> > +                   ksev_status.state == SEV_GSTATE_LSECRET,
> > +                   "Unexpected guest state: %d", ksev_status.state);
> > +
> > +       kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL);
> > +
> > +       kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> > +       TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
> > +                   "Unexpected guest state: %d", ksev_status.state);
> > +}
> > --
> > 2.25.1
> >
> 
> This is phenomenal. I'll try to send feedback on the other patches in
> the first batch of 7 sooner rather than later. I haven't looked past
> patch #7 yet. Let me know what you think about my first comment, on
> whether we can get all pre-existing tests to run under SEV, or that's
> a bad idea. I probably haven't given it as much thought as you have.

Thanks for looking! I think it would be great if we could get to a point
where all the SEV/CoCo stuff can happen transparently, but might take some
time to get all the groundwork in place, and likely some churn in the
affected test cases.

-Mike

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Michael Roth]

On Mon, Oct 11, 2021 at 08:15:37PM -0500, Michael Roth wrote:
> On Sun, Oct 10, 2021 at 08:17:00PM -0700, Marc Orr wrote:
> > On Wed, Oct 6, 2021 at 1:40 PM Michael Roth <michael.roth@amd.com> wrote:
> > >
> > > Add interfaces to allow tests to create/manage SEV guests. The
> > > additional state associated with these guests is encapsulated in a new
> > > struct sev_vm, which is a light wrapper around struct kvm_vm. These
> > > VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
> > > under the covers to configure and sync up with the core kvm_util
> > > library on what should/shouldn't be treated as encrypted memory.
> > >
> > > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > > ---
> > >  tools/testing/selftests/kvm/Makefile          |   1 +
> > >  .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
> > >  tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
> > >  3 files changed, 366 insertions(+)
> > >  create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
> > >  create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
> > >
> > > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> > > index 5832f510a16c..c7a5e1c69e0c 100644
> > > --- a/tools/testing/selftests/kvm/Makefile
> > > +++ b/tools/testing/selftests/kvm/Makefile
> > > @@ -35,6 +35,7 @@ endif
> > >
> > >  LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
> > >  LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
> > > +LIBKVM_x86_64 += lib/x86_64/sev.c
> > 
> > Regarding RFC-level feedback: First off, I'm super jazzed with what
> > I'm seeing so far! (While this is my first review, I've been studying
> > the patches up through the SEV boot test, i.e., patch #7). One thing
> > I'm wondering is: the way this is structured is to essentially split
> > the test cases into non-SEV and SEV. I'm wondering how hard it would
> > be to add some flag or environment variable to set up pre-existing
> > tests to run under SEV. Or is this something you all thought about,
> > and decided that it does not make sense?
> > 
> > Looking at how the guest memory is handled, it seems like it's not far
> > off from handling SEV transparently across all test cases. I'd think
> > that we could just default all memory to use the encryption bit, and
> > then have test cases, such as the test case in patch #7, clear the
> > encryption bit for shared pages. However, I think the VM creation
> > would need a bit more refactoring to work with other test cases.
> 
> I think it's possible, but there's a few missing pieces:
> 
> 1) As you indicated, existing tests which rely on vm_create(),
>    vm_create_default(), vm_create_default_with_vcpus(), etc. would either
>    need to be updated with whatever new interface provides this 'use-sev'
>    flag, or it would need to happen underneath the covers based on said
>    environment variable/global/etc. There's also the question of where
>    to hook in the sev_vm_launch_start() hooks. Maybe the first time a
>    vcpu_run() is issued? Or maybe some explict call each test will need
>    to be updated to call just prior to initial execution.
> 
> 2) Many of the existing tests use the GUESY_SYNC/ucall stuff to handle
>    synchronization between host userspace and guest kernel, which relies on
>    guests issuing PIO instructions to particular port addresses to cause an
>    exit back to host userspace, with various parameters passed via register
>    arguments.
> 
>    - For SEV this would almost work as-is, but some tests might rely on
>      things like memory addresses being passed in this way so would need
>      to audit the code and mark that memory as shared where needed.
> 
>    - For SEV-ES/SEV-SNP, there's a bit more work since:
> 
>      - The registers will not be accessible through the existing
>        KVM_GET_REGS mechanism. It may be possible to set some flag/hook to
>        set/access arguments through some other mechanism like a shared
>        buffer for certain VM types though.
> 
>      - Additionally, the #VC handler only supports CPUID currently, and
>        leverages that fact to avoid doing any significant instruction
>        decoding. Instead the SEV tests use HLT instructions to handle exits
>        to host userspace, which may not work for some tests. So unless
>        there's some other mechanism that SEV/non-SEV tests could utilize
>        rather that PIO, the #VC handler would need to support PIO, which
>        would be nice to have either way, but would likely involve
>        pulling in the intruction decoder library used in the kernel, or
>        some subset/re-implementation of it at least.
> 
> 3) Similar to SEV-ES/SEV-SNP requirements for 1), tests which generate
>    PIO/MMIO and other NAE events would need appropriate support for those
>    events in the #VC handler. Nice-to-have either way, but not sure atm
>    how much it would be to implement all of that. Also any tests relying
>    on things like KVM_GET_REGS/KVM_GET_SREGS are non-starters.

One more I should mention:

4) After encryption, the page table is no longer usable for translations by
   stuff like addr_gva2gpa(), so tests would either need to be
   audited/updated to do these translations upfront and only rely on
   cached/stored values thereafter, or perhaps a "shadow" copy could be
   maintained by kvm_util so the translations will continue to work
   after encryption.

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Paolo Bonzini]

On 12/10/21 14:55, Michael Roth wrote:
> One more I should mention:
> 
> 4) After encryption, the page table is no longer usable for translations by
>     stuff like addr_gva2gpa(), so tests would either need to be
>     audited/updated to do these translations upfront and only rely on
>     cached/stored values thereafter, or perhaps a "shadow" copy could be
>     maintained by kvm_util so the translations will continue to work
>     after encryption.

Yeah, this is a big one.  Considering that a lot of the selftests are 
for specific bugs, the benefit in running them with SEV is relatively 
low.  That said, there could be some simple tests where it makes sense, 
so it'd be nice to plan a little ahead so that it isn't _too_ difficult.

Paolo

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Mingwei Zhang]

>
> >
> > > +#define SEV_FW_REQ_VER_MAJOR   1
> > > +#define SEV_FW_REQ_VER_MINOR   30
> >
> > Where does the requirement for this minimum version come from? Maybe
> > add a comment?
> >
> > Edit: Is this for patches later on in the series that exercise SNP? If
> > so, I think it would be better to add a check like this in the test
> > itself, rather than globally. I happened to test this on a machine
> > with a very old PSP FW, 0.22, and the SEV test added in patch #7 seems
> > to work fine with this ancient PSP FW.
>
> Ah, yes, this was mostly for SNP support. I'll implement a separate minimum
> version for SEV/SEV-ES.
>

I want to ask the same thing, I tried to run the sev selftest today
and I was blocked by this minimum version number... BTW: I suspect if
I want to update the SEV firmware I have to update the BIOS myself?
So, it would be good to know what is the actual minimum for SEV.

In addition, maybe that's side effect, I see a warning when building the kernel:

"module ccp.ko requires firmware amd/amd_sev_fam19h_model0xh.sbin"

Maybe I need some hints from you? Or maybe it is just harmless. I did
double checked and it looks like I was using either
amd_sev_fam17h_model3xh.sbin or amd_sev_fam17h_model0xh.sbin

Thanks.
-Mingwei

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Tom Lendacky]

On 11/4/21 12:25 AM, Mingwei Zhang wrote:
>>
>>>
>>>> +#define SEV_FW_REQ_VER_MAJOR   1
>>>> +#define SEV_FW_REQ_VER_MINOR   30
>>>
>>> Where does the requirement for this minimum version come from? Maybe
>>> add a comment?
>>>
>>> Edit: Is this for patches later on in the series that exercise SNP? If
>>> so, I think it would be better to add a check like this in the test
>>> itself, rather than globally. I happened to test this on a machine
>>> with a very old PSP FW, 0.22, and the SEV test added in patch #7 seems
>>> to work fine with this ancient PSP FW.
>>
>> Ah, yes, this was mostly for SNP support. I'll implement a separate minimum
>> version for SEV/SEV-ES.
>>
> 
> I want to ask the same thing, I tried to run the sev selftest today
> and I was blocked by this minimum version number... BTW: I suspect if
> I want to update the SEV firmware I have to update the BIOS myself?

The SEV firmware is updatable at module load time through the
DOWNLOAD_FIRMWARE command.

> So, it would be good to know what is the actual minimum for SEV.
> 
> In addition, maybe that's side effect, I see a warning when building the kernel:
> 
> "module ccp.ko requires firmware amd/amd_sev_fam19h_model0xh.sbin"

The firmware images reside (typically) in /lib/firmware/amd/. There is a
new version for fam19h that you can copy into that directory at:

https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/tree/amd

or

https://developer.amd.com/sev/ under the Links & Downloads section (Note,
if retrieved from here you will/may need to rename the .sbin file to match
the name mentioned above).

> 
> Maybe I need some hints from you? Or maybe it is just harmless. I did
> double checked and it looks like I was using either
> amd_sev_fam17h_model3xh.sbin or amd_sev_fam17h_model0xh.sbin

If you're on a fam19h machine, the fam17h builds won't be used.

Thanks,
Tom

> 
> Thanks.
> -Mingwei
> 

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Krish Sadhukhan]

On 10/6/21 1:37 PM, Michael Roth wrote:
> Add interfaces to allow tests to create/manage SEV guests. The
> additional state associated with these guests is encapsulated in a new
> struct sev_vm, which is a light wrapper around struct kvm_vm. These
> VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
> under the covers to configure and sync up with the core kvm_util
> library on what should/shouldn't be treated as encrypted memory.
>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>   tools/testing/selftests/kvm/Makefile          |   1 +
>   .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
>   tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
>   3 files changed, 366 insertions(+)
>   create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
>   create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
>
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index 5832f510a16c..c7a5e1c69e0c 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -35,6 +35,7 @@ endif
>   
>   LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
>   LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
> +LIBKVM_x86_64 += lib/x86_64/sev.c
>   LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
>   LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
>   
> diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
> new file mode 100644
> index 000000000000..d2f41b131ecc
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
> @@ -0,0 +1,62 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Helpers used for SEV guests
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +#ifndef SELFTEST_KVM_SEV_H
> +#define SELFTEST_KVM_SEV_H
> +
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include "kvm_util.h"
> +
> +#define SEV_DEV_PATH		"/dev/sev"
> +#define SEV_FW_REQ_VER_MAJOR	1
> +#define SEV_FW_REQ_VER_MINOR	30
> +
> +#define SEV_POLICY_NO_DBG	(1UL << 0)
> +#define SEV_POLICY_ES		(1UL << 2)
> +
> +#define SEV_GUEST_ASSERT(sync, token, _cond) do {	\
> +	if (!(_cond))					\
> +		sev_guest_abort(sync, token, 0);	\
> +} while (0)
> +
> +enum {
> +	SEV_GSTATE_UNINIT = 0,
> +	SEV_GSTATE_LUPDATE,
> +	SEV_GSTATE_LSECRET,
> +	SEV_GSTATE_RUNNING,
> +};
> +
> +struct sev_sync_data {
> +	uint32_t token;
> +	bool pending;
> +	bool done;
> +	bool aborted;
> +	uint64_t info;
> +};
> +
> +struct sev_vm;
> +
> +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +
> +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token);
> +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token);
> +
> +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data);
> +struct kvm_vm *sev_get_vm(struct sev_vm *sev);
> +uint8_t sev_get_enc_bit(struct sev_vm *sev);
> +
> +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages);
> +void sev_vm_free(struct sev_vm *sev);
> +void sev_vm_launch(struct sev_vm *sev);
> +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
> +void sev_vm_launch_finish(struct sev_vm *sev);
> +
> +#endif /* SELFTEST_KVM_SEV_H */
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> new file mode 100644
> index 000000000000..adda3b396566
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> @@ -0,0 +1,303 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Helpers used for SEV guests
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include "kvm_util.h"
> +#include "linux/psp-sev.h"
> +#include "processor.h"
> +#include "sev.h"
> +
> +#define PAGE_SHIFT		12
> +#define PAGE_SIZE		(1UL << PAGE_SHIFT)
> +
> +struct sev_vm {
> +	struct kvm_vm *vm;
> +	int fd;
> +	int enc_bit;
> +	uint32_t sev_policy;
> +};
> +
> +/* Helpers for coordinating between guests and test harness. */
> +
> +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +	sync->token = token;
> +	sync->info = info;
> +	sync->pending = true;
> +
> +	asm volatile("hlt" : : : "memory");
> +}
> +
> +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +	while (true) {
> +		sync->done = true;
> +		sev_guest_sync(sync, token, info);
> +	}
> +}
> +
> +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +	while (true) {
> +		sync->aborted = true;
> +		sev_guest_sync(sync, token, info);
> +	}
> +}
> +
> +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token)
> +{
> +	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> +		    "unexpected exit reason: %u (%s)",
> +		    run->exit_reason, exit_reason_str(run->exit_reason));
> +	TEST_ASSERT(sync->token == token,
> +		    "unexpected guest token, expected %d, got: %d", token,
> +		    sync->token);
> +	TEST_ASSERT(!sync->done, "unexpected guest state");
> +	TEST_ASSERT(!sync->aborted, "unexpected guest state");
> +	sync->pending = false;
> +}
> +
> +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token)
> +{
> +	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> +		    "unexpected exit reason: %u (%s)",
> +		    run->exit_reason, exit_reason_str(run->exit_reason));
> +	TEST_ASSERT(sync->token == token,
> +		    "unexpected guest token, expected %d, got: %d", token,
> +		    sync->token);
> +	TEST_ASSERT(sync->done, "unexpected guest state");
> +	TEST_ASSERT(!sync->aborted, "unexpected guest state");
> +	sync->pending = false;
> +}
> +
> +/* Common SEV helpers/accessors. */
> +
> +struct kvm_vm *sev_get_vm(struct sev_vm *sev)
> +{
> +	return sev->vm;
> +}
> +
> +uint8_t sev_get_enc_bit(struct sev_vm *sev)
> +{
> +	return sev->enc_bit;
> +}
> +
> +void sev_ioctl(int sev_fd, int cmd, void *data)
> +{
> +	int ret;
> +	struct sev_issue_cmd arg;
> +
> +	arg.cmd = cmd;
> +	arg.data = (unsigned long)data;
> +	ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg);
> +	TEST_ASSERT(ret == 0,
> +		    "SEV ioctl %d failed, error: %d, fw_error: %d",
> +		    cmd, ret, arg.error);
> +}
> +
> +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
> +{
> +	struct kvm_sev_cmd arg = {0};
> +	int ret;
> +
> +	arg.id = cmd;
> +	arg.sev_fd = sev->fd;
> +	arg.data = (__u64)data;
> +
> +	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_OP, &arg);
> +	TEST_ASSERT(ret == 0,
> +		    "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d",
> +		    cmd, ret, errno, strerror(errno), arg.error);
> +}
> +
> +/* Local helpers. */
> +
> +static void
> +sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)


Since 'region' is used in every naming, it's better to call it 
sev_register_user_region or sev_register_userspace_region for the sake 
of consistency.

> +{
> +	struct kvm_enc_region range = {0};
> +	int ret;
> +
> +	pr_debug("register_user_range: hva: %p, size: %lu\n", hva, size);
> +
> +	range.addr = (__u64)hva;
> +	range.size = size;
> +
> +	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_REG_REGION, &range);
> +	TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno);
> +}
> +
> +static void
> +sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
> +{
> +	struct kvm_sev_launch_update_data ksev_update_data = {0};
> +
> +	pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
> +
> +	ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
> +	ksev_update_data.len = size;
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
> +}
> +
> +static void sev_encrypt(struct sev_vm *sev)
> +{
> +	struct sparsebit *enc_phy_pages;
> +	struct kvm_vm *vm = sev->vm;
> +	sparsebit_idx_t pg = 0;
> +	vm_paddr_t gpa_start;
> +	uint64_t memory_size;
> +
> +	/* Only memslot 0 supported for now. */
> +	enc_phy_pages = vm_get_encrypted_phy_pages(sev->vm, 0, &gpa_start, &memory_size);


vm_get_encrypted_phy_pages() allocates a duplicate sparsebit. I am 
wondering if it is possible for the function to just give a pointer to 
'region->encrypted_phy_pages' so the allocation and freeing of memory 
can be avoided.

> +	TEST_ASSERT(enc_phy_pages, "Unable to retrieve encrypted pages bitmap");
> +	while (pg < (memory_size / vm_get_page_size(vm))) {
> +		sparsebit_idx_t pg_cnt;
> +
> +		if (sparsebit_is_clear(enc_phy_pages, pg)) {
> +			pg = sparsebit_next_set(enc_phy_pages, pg);
> +			if (!pg)
> +				break;
> +		}
> +
> +		pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg;
> +		if (pg_cnt <= 0)
> +			pg_cnt = 1;
> +
> +		sev_encrypt_phy_range(sev,
> +				      gpa_start + pg * vm_get_page_size(vm),
> +				      pg_cnt * vm_get_page_size(vm));
> +		pg += pg_cnt;
> +	}
> +
> +	sparsebit_free(&enc_phy_pages);
> +}
> +
> +/* SEV VM implementation. */
> +
> +static struct sev_vm *sev_common_create(struct kvm_vm *vm)


Can there be a better name like, sev_vm_alloc because it's essentially 
allocating and initializing a sev_vm data structure.

> +{
> +	struct sev_user_data_status sev_status = {0};
> +	uint32_t eax, ebx, ecx, edx;
> +	struct sev_vm *sev;
> +	int sev_fd;
> +
> +	sev_fd = open(SEV_DEV_PATH, O_RDWR);
> +	if (sev_fd < 0) {
> +		pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n",
> +			SEV_DEV_PATH, sev_fd);
> +		return NULL;
> +	}
> +
> +	sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status);
> +
> +	if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR ||
> +	      (sev_status.api_major == SEV_FW_REQ_VER_MAJOR &&
> +	       sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) {
> +		pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n",
> +			sev_status.api_major, sev_status.api_minor, sev_status.build,
> +			SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR);
> +		return NULL;
> +	}
> +
> +	sev = calloc(1, sizeof(*sev));
> +	sev->fd = sev_fd;
> +	sev->vm = vm;
> +
> +	/* Get encryption bit via CPUID. */
> +	eax = 0x8000001f;
> +	ecx = 0;
> +	cpuid(&eax, &ebx, &ecx, &edx);
> +	sev->enc_bit = ebx & 0x3F;
> +
> +	return sev;
> +}
> +
> +static void sev_common_free(struct sev_vm *sev)
> +{
> +	close(sev->fd);
> +	free(sev);
> +}
> +
> +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
> +{
> +	struct sev_vm *sev;
> +	struct kvm_vm *vm;
> +
> +	/* Need to handle memslots after init, and after setting memcrypt. */
> +	vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
> +	sev = sev_common_create(vm);
> +	if (!sev)
> +		return NULL;
> +	sev->sev_policy = policy;
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
> +
> +	vm_set_memory_encryption(vm, true, true, sev->enc_bit);
> +	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
> +	sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
> +
> +	pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
> +		sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
> +
> +	return sev;
> +}
> +
> +void sev_vm_free(struct sev_vm *sev)
> +{
> +	kvm_vm_free(sev->vm);
> +	sev_common_free(sev);
> +}
> +
> +void sev_vm_launch(struct sev_vm *sev)
> +{
> +	struct kvm_sev_launch_start ksev_launch_start = {0};
> +	struct kvm_sev_guest_status ksev_status = {0};
> +
> +	ksev_launch_start.policy = sev->sev_policy;
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start);
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +	TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy.");
> +	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE,
> +		    "Unexpected guest state: %d", ksev_status.state);
> +
> +	sev_encrypt(sev);
> +}
> +
> +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
> +{
> +	struct kvm_sev_launch_measure ksev_launch_measure = {0};
> +	struct kvm_sev_guest_status ksev_guest_status = {0};
> +
> +	ksev_launch_measure.len = 256;
> +	ksev_launch_measure.uaddr = (__u64)measurement;
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure);
> +
> +	/* Measurement causes a state transition, check that. */
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status);
> +	TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET,
> +		    "Unexpected guest state: %d", ksev_guest_status.state);
> +}
> +
> +void sev_vm_launch_finish(struct sev_vm *sev)
> +{
> +	struct kvm_sev_guest_status ksev_status = {0};
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE ||
> +		    ksev_status.state == SEV_GSTATE_LSECRET,
> +		    "Unexpected guest state: %d", ksev_status.state);
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL);
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +	TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
> +		    "Unexpected guest state: %d", ksev_status.state);
> +}

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Krish Sadhukhan]

On 10/6/21 1:37 PM, Michael Roth wrote:
> Add interfaces to allow tests to create/manage SEV guests. The
> additional state associated with these guests is encapsulated in a new
> struct sev_vm, which is a light wrapper around struct kvm_vm. These
> VMs will use vm_set_memory_encryption() and vm_get_encrypted_phy_pages()
> under the covers to configure and sync up with the core kvm_util
> library on what should/shouldn't be treated as encrypted memory.
>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>   tools/testing/selftests/kvm/Makefile          |   1 +
>   .../selftests/kvm/include/x86_64/sev.h        |  62 ++++
>   tools/testing/selftests/kvm/lib/x86_64/sev.c  | 303 ++++++++++++++++++
>   3 files changed, 366 insertions(+)
>   create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
>   create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
>
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index 5832f510a16c..c7a5e1c69e0c 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -35,6 +35,7 @@ endif
>   
>   LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/rbtree.c lib/sparsebit.c lib/test_util.c lib/guest_modes.c lib/perf_test_util.c
>   LIBKVM_x86_64 = lib/x86_64/apic.c lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/svm.c lib/x86_64/ucall.c lib/x86_64/handlers.S
> +LIBKVM_x86_64 += lib/x86_64/sev.c
>   LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c lib/aarch64/handlers.S
>   LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c lib/s390x/diag318_test_handler.c
>   
> diff --git a/tools/testing/selftests/kvm/include/x86_64/sev.h b/tools/testing/selftests/kvm/include/x86_64/sev.h
> new file mode 100644
> index 000000000000..d2f41b131ecc
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/include/x86_64/sev.h
> @@ -0,0 +1,62 @@
> +/* SPDX-License-Identifier: GPL-2.0-only */
> +/*
> + * Helpers used for SEV guests
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +#ifndef SELFTEST_KVM_SEV_H
> +#define SELFTEST_KVM_SEV_H
> +
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include "kvm_util.h"
> +
> +#define SEV_DEV_PATH		"/dev/sev"
> +#define SEV_FW_REQ_VER_MAJOR	1
> +#define SEV_FW_REQ_VER_MINOR	30
> +
> +#define SEV_POLICY_NO_DBG	(1UL << 0)
> +#define SEV_POLICY_ES		(1UL << 2)
> +
> +#define SEV_GUEST_ASSERT(sync, token, _cond) do {	\
> +	if (!(_cond))					\
> +		sev_guest_abort(sync, token, 0);	\
> +} while (0)
> +
> +enum {
> +	SEV_GSTATE_UNINIT = 0,
> +	SEV_GSTATE_LUPDATE,
> +	SEV_GSTATE_LSECRET,
> +	SEV_GSTATE_RUNNING,
> +};
> +
> +struct sev_sync_data {
> +	uint32_t token;
> +	bool pending;
> +	bool done;
> +	bool aborted;


Instead of having three different members, 'pending', done' and 'abort', 
and their corresponding functions, is it possible to use a single member 
and a single function with #defines for the three states ? This may be 
better if we need to add more sync states in the future.

> +	uint64_t info;
> +};
> +
> +struct sev_vm;
> +
> +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info);
> +
> +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token);
> +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token);
> +
> +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data);
> +struct kvm_vm *sev_get_vm(struct sev_vm *sev);
> +uint8_t sev_get_enc_bit(struct sev_vm *sev);
> +
> +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages);
> +void sev_vm_free(struct sev_vm *sev);
> +void sev_vm_launch(struct sev_vm *sev);
> +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement);
> +void sev_vm_launch_finish(struct sev_vm *sev);
> +
> +#endif /* SELFTEST_KVM_SEV_H */
> diff --git a/tools/testing/selftests/kvm/lib/x86_64/sev.c b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> new file mode 100644
> index 000000000000..adda3b396566
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/lib/x86_64/sev.c
> @@ -0,0 +1,303 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Helpers used for SEV guests
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +
> +#include <stdint.h>
> +#include <stdbool.h>
> +#include "kvm_util.h"
> +#include "linux/psp-sev.h"
> +#include "processor.h"
> +#include "sev.h"
> +
> +#define PAGE_SHIFT		12
> +#define PAGE_SIZE		(1UL << PAGE_SHIFT)
> +
> +struct sev_vm {
> +	struct kvm_vm *vm;
> +	int fd;
> +	int enc_bit;
> +	uint32_t sev_policy;
> +};
> +
> +/* Helpers for coordinating between guests and test harness. */
> +
> +void sev_guest_sync(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +	sync->token = token;
> +	sync->info = info;
> +	sync->pending = true;
> +
> +	asm volatile("hlt" : : : "memory");
> +}
> +
> +void sev_guest_done(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +	while (true) {
> +		sync->done = true;
> +		sev_guest_sync(sync, token, info);
> +	}
> +}
> +
> +void sev_guest_abort(struct sev_sync_data *sync, uint32_t token, uint64_t info)
> +{
> +	while (true) {
> +		sync->aborted = true;
> +		sev_guest_sync(sync, token, info);
> +	}
> +}
> +
> +void sev_check_guest_sync(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token)
> +{
> +	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> +		    "unexpected exit reason: %u (%s)",
> +		    run->exit_reason, exit_reason_str(run->exit_reason));
> +	TEST_ASSERT(sync->token == token,
> +		    "unexpected guest token, expected %d, got: %d", token,
> +		    sync->token);
> +	TEST_ASSERT(!sync->done, "unexpected guest state");
> +	TEST_ASSERT(!sync->aborted, "unexpected guest state");
> +	sync->pending = false;
> +}
> +
> +void sev_check_guest_done(struct kvm_run *run, struct sev_sync_data *sync,
> +			  uint32_t token)
> +{
> +	TEST_ASSERT(run->exit_reason == KVM_EXIT_HLT,
> +		    "unexpected exit reason: %u (%s)",
> +		    run->exit_reason, exit_reason_str(run->exit_reason));
> +	TEST_ASSERT(sync->token == token,
> +		    "unexpected guest token, expected %d, got: %d", token,
> +		    sync->token);
> +	TEST_ASSERT(sync->done, "unexpected guest state");
> +	TEST_ASSERT(!sync->aborted, "unexpected guest state");
> +	sync->pending = false;
> +}
> +
> +/* Common SEV helpers/accessors. */
> +
> +struct kvm_vm *sev_get_vm(struct sev_vm *sev)
> +{
> +	return sev->vm;
> +}
> +
> +uint8_t sev_get_enc_bit(struct sev_vm *sev)
> +{
> +	return sev->enc_bit;
> +}
> +
> +void sev_ioctl(int sev_fd, int cmd, void *data)
> +{
> +	int ret;
> +	struct sev_issue_cmd arg;
> +
> +	arg.cmd = cmd;
> +	arg.data = (unsigned long)data;
> +	ret = ioctl(sev_fd, SEV_ISSUE_CMD, &arg);
> +	TEST_ASSERT(ret == 0,
> +		    "SEV ioctl %d failed, error: %d, fw_error: %d",
> +		    cmd, ret, arg.error);
> +}
> +
> +void kvm_sev_ioctl(struct sev_vm *sev, int cmd, void *data)
> +{
> +	struct kvm_sev_cmd arg = {0};
> +	int ret;
> +
> +	arg.id = cmd;
> +	arg.sev_fd = sev->fd;
> +	arg.data = (__u64)data;
> +
> +	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_OP, &arg);
> +	TEST_ASSERT(ret == 0,
> +		    "SEV KVM ioctl %d failed, rc: %i errno: %i (%s), fw_error: %d",
> +		    cmd, ret, errno, strerror(errno), arg.error);
> +}
> +
> +/* Local helpers. */
> +
> +static void
> +sev_register_user_range(struct sev_vm *sev, void *hva, uint64_t size)
> +{
> +	struct kvm_enc_region range = {0};
> +	int ret;
> +
> +	pr_debug("register_user_range: hva: %p, size: %lu\n", hva, size);
> +
> +	range.addr = (__u64)hva;
> +	range.size = size;
> +
> +	ret = ioctl(vm_get_fd(sev->vm), KVM_MEMORY_ENCRYPT_REG_REGION, &range);
> +	TEST_ASSERT(ret == 0, "failed to register user range, errno: %i\n", errno);
> +}
> +
> +static void
> +sev_encrypt_phy_range(struct sev_vm *sev, vm_paddr_t gpa, uint64_t size)
> +{
> +	struct kvm_sev_launch_update_data ksev_update_data = {0};
> +
> +	pr_debug("encrypt_phy_range: addr: 0x%lx, size: %lu\n", gpa, size);
> +
> +	ksev_update_data.uaddr = (__u64)addr_gpa2hva(sev->vm, gpa);
> +	ksev_update_data.len = size;
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_UPDATE_DATA, &ksev_update_data);
> +}
> +
> +static void sev_encrypt(struct sev_vm *sev)
> +{
> +	struct sparsebit *enc_phy_pages;
> +	struct kvm_vm *vm = sev->vm;
> +	sparsebit_idx_t pg = 0;
> +	vm_paddr_t gpa_start;
> +	uint64_t memory_size;
> +
> +	/* Only memslot 0 supported for now. */
> +	enc_phy_pages = vm_get_encrypted_phy_pages(sev->vm, 0, &gpa_start, &memory_size);
> +	TEST_ASSERT(enc_phy_pages, "Unable to retrieve encrypted pages bitmap");
> +	while (pg < (memory_size / vm_get_page_size(vm))) {
> +		sparsebit_idx_t pg_cnt;
> +
> +		if (sparsebit_is_clear(enc_phy_pages, pg)) {
> +			pg = sparsebit_next_set(enc_phy_pages, pg);
> +			if (!pg)
> +				break;
> +		}
> +
> +		pg_cnt = sparsebit_next_clear(enc_phy_pages, pg) - pg;
> +		if (pg_cnt <= 0)
> +			pg_cnt = 1;
> +
> +		sev_encrypt_phy_range(sev,
> +				      gpa_start + pg * vm_get_page_size(vm),
> +				      pg_cnt * vm_get_page_size(vm));
> +		pg += pg_cnt;
> +	}
> +
> +	sparsebit_free(&enc_phy_pages);
> +}
> +
> +/* SEV VM implementation. */
> +
> +static struct sev_vm *sev_common_create(struct kvm_vm *vm)
> +{
> +	struct sev_user_data_status sev_status = {0};
> +	uint32_t eax, ebx, ecx, edx;
> +	struct sev_vm *sev;
> +	int sev_fd;
> +
> +	sev_fd = open(SEV_DEV_PATH, O_RDWR);
> +	if (sev_fd < 0) {
> +		pr_info("Failed to open SEV device, path: %s, error: %d, skipping test.\n",
> +			SEV_DEV_PATH, sev_fd);
> +		return NULL;
> +	}
> +
> +	sev_ioctl(sev_fd, SEV_PLATFORM_STATUS, &sev_status);
> +
> +	if (!(sev_status.api_major > SEV_FW_REQ_VER_MAJOR ||
> +	      (sev_status.api_major == SEV_FW_REQ_VER_MAJOR &&
> +	       sev_status.api_minor >= SEV_FW_REQ_VER_MINOR))) {
> +		pr_info("SEV FW version too old. Have API %d.%d (build: %d), need %d.%d, skipping test.\n",
> +			sev_status.api_major, sev_status.api_minor, sev_status.build,
> +			SEV_FW_REQ_VER_MAJOR, SEV_FW_REQ_VER_MINOR);
> +		return NULL;
> +	}
> +
> +	sev = calloc(1, sizeof(*sev));
> +	sev->fd = sev_fd;
> +	sev->vm = vm;
> +
> +	/* Get encryption bit via CPUID. */
> +	eax = 0x8000001f;
> +	ecx = 0;
> +	cpuid(&eax, &ebx, &ecx, &edx);
> +	sev->enc_bit = ebx & 0x3F;
> +
> +	return sev;
> +}
> +
> +static void sev_common_free(struct sev_vm *sev)
> +{
> +	close(sev->fd);
> +	free(sev);
> +}
> +
> +struct sev_vm *sev_vm_create(uint32_t policy, uint64_t npages)
> +{
> +	struct sev_vm *sev;
> +	struct kvm_vm *vm;
> +
> +	/* Need to handle memslots after init, and after setting memcrypt. */
> +	vm = vm_create(VM_MODE_DEFAULT, 0, O_RDWR);
> +	sev = sev_common_create(vm);
> +	if (!sev)
> +		return NULL;
> +	sev->sev_policy = policy;
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_INIT, NULL);
> +
> +	vm_set_memory_encryption(vm, true, true, sev->enc_bit);
> +	vm_userspace_mem_region_add(vm, VM_MEM_SRC_ANONYMOUS, 0, 0, npages, 0);
> +	sev_register_user_range(sev, addr_gpa2hva(vm, 0), npages * vm_get_page_size(vm));
> +
> +	pr_info("SEV guest created, policy: 0x%x, size: %lu KB\n",
> +		sev->sev_policy, npages * vm_get_page_size(vm) / 1024);
> +
> +	return sev;
> +}
> +
> +void sev_vm_free(struct sev_vm *sev)
> +{
> +	kvm_vm_free(sev->vm);
> +	sev_common_free(sev);
> +}
> +
> +void sev_vm_launch(struct sev_vm *sev)
> +{
> +	struct kvm_sev_launch_start ksev_launch_start = {0};
> +	struct kvm_sev_guest_status ksev_status = {0};
> +
> +	ksev_launch_start.policy = sev->sev_policy;
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_START, &ksev_launch_start);
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +	TEST_ASSERT(ksev_status.policy == sev->sev_policy, "Incorrect guest policy.");
> +	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE,
> +		    "Unexpected guest state: %d", ksev_status.state);
> +
> +	sev_encrypt(sev);
> +}
> +
> +void sev_vm_measure(struct sev_vm *sev, uint8_t *measurement)
> +{
> +	struct kvm_sev_launch_measure ksev_launch_measure = {0};
> +	struct kvm_sev_guest_status ksev_guest_status = {0};
> +
> +	ksev_launch_measure.len = 256;
> +	ksev_launch_measure.uaddr = (__u64)measurement;
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_MEASURE, &ksev_launch_measure);
> +
> +	/* Measurement causes a state transition, check that. */
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_guest_status);
> +	TEST_ASSERT(ksev_guest_status.state == SEV_GSTATE_LSECRET,
> +		    "Unexpected guest state: %d", ksev_guest_status.state);
> +}
> +
> +void sev_vm_launch_finish(struct sev_vm *sev)

Just like you named it after the command LAUNCH_FINISH, it's better to 
name the other functions based on the command they are executing, for 
the sake of consistency:

     sev_vm_launch_measure,    sev_vm_launch_start

> +{
> +	struct kvm_sev_guest_status ksev_status = {0};
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +	TEST_ASSERT(ksev_status.state == SEV_GSTATE_LUPDATE ||
> +		    ksev_status.state == SEV_GSTATE_LSECRET,
> +		    "Unexpected guest state: %d", ksev_status.state);
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_LAUNCH_FINISH, NULL);
> +
> +	kvm_sev_ioctl(sev, KVM_SEV_GUEST_STATUS, &ksev_status);
> +	TEST_ASSERT(ksev_status.state == SEV_GSTATE_RUNNING,
> +		    "Unexpected guest state: %d", ksev_status.state);
> +}

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Paolo Bonzini]

On 06/10/21 22:37, Michael Roth wrote:
> +struct sev_sync_data {
> +	uint32_t token;
> +	bool pending;
> +	bool done;
> +	bool aborted;
> +	uint64_t info;
> +};
> +

Please add a comment explaining roughly the design and what the fields 
are for.  Maybe the bools can be replaced by an enum { DONE, ABORT, 
SYNC, RUNNING } (running is for pending==false)?

Also, for the part that you can feel free to ignore: this seems to be 
similar to the ucall mechanism.  Is it possible to implement the ucall 
interface in terms of this one (or vice versa)?

One idea could be to:

- move ucall to the main lib/ directory

- make it use a struct of function pointers, whose default 
implementation would be in the existing lib/ARCH/ucall.c files

- add a function to register the struct for the desired implementation

- make sev.c register its own implementation

Thanks,

Paolo

Re: [RFC 06/16] KVM: selftests: add library for creating/interacting with SEV guests

[Michael Roth]

On Thu, Oct 21, 2021 at 05:39:34PM +0200, Paolo Bonzini wrote:
> On 06/10/21 22:37, Michael Roth wrote:
> > +struct sev_sync_data {
> > +	uint32_t token;
> > +	bool pending;
> > +	bool done;
> > +	bool aborted;
> > +	uint64_t info;
> > +};
> > +
> 
> Please add a comment explaining roughly the design and what the fields are
> for.  Maybe the bools can be replaced by an enum { DONE, ABORT, SYNC,
> RUNNING } (running is for pending==false)?

That makes sense. And SYNC is basically pending==true.

Though since it would be the test code calling sev_check_guest_sync() that
sets pending to true after each sync, "RUNNABLE" might be a better name
since whether it's actually running depends on a separate call to
vcpu_run().

> 
> Also, for the part that you can feel free to ignore: this seems to be
> similar to the ucall mechanism.  Is it possible to implement the ucall
> interface in terms of this one (or vice versa)?
> 
> One idea could be to:
> 
> - move ucall to the main lib/ directory
> 
> - make it use a struct of function pointers, whose default implementation
> would be in the existing lib/ARCH/ucall.c files
> 
> - add a function to register the struct for the desired implementation
> 
> - make sev.c register its own implementation

That seems doable. We'd also need to register an opaque pointer that, in the
case of SEV, would be for the shared page used for syncing. The guest would
also need the pointers for the ops/opaque, but ucall_init() could
additionally set some globals to provide the GVAs for them in the guest
environment.

Will look at that for the next spin.

> 
> Thanks,
> 
> Paolo
> 

[RFC 07/16] KVM: selftests: add SEV boot tests

[Michael Roth]

A common aspect of booting SEV guests is checking related CPUID/MSR
bits and accessing shared/private memory. Add a basic test to cover
this.

This test will be expanded to cover basic boot of SEV-ES and SEV-SNP in
subsequent patches.

Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 tools/testing/selftests/kvm/.gitignore        |   1 +
 tools/testing/selftests/kvm/Makefile          |   1 +
 .../selftests/kvm/x86_64/sev_all_boot_test.c  | 252 ++++++++++++++++++
 3 files changed, 254 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c

diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
index 0709af0144c8..824f100bec2a 100644
--- a/tools/testing/selftests/kvm/.gitignore
+++ b/tools/testing/selftests/kvm/.gitignore
@@ -38,6 +38,7 @@
 /x86_64/xen_vmcall_test
 /x86_64/xss_msr_test
 /x86_64/vmx_pmu_msrs_test
+/x86_64/sev_all_boot_test
 /access_tracking_perf_test
 /demand_paging_test
 /dirty_log_test
diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index c7a5e1c69e0c..aa8901bdbd22 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -72,6 +72,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/tsc_msrs_test
 TEST_GEN_PROGS_x86_64 += x86_64/vmx_pmu_msrs_test
 TEST_GEN_PROGS_x86_64 += x86_64/xen_shinfo_test
 TEST_GEN_PROGS_x86_64 += x86_64/xen_vmcall_test
+TEST_GEN_PROGS_x86_64 += x86_64/sev_all_boot_test
 TEST_GEN_PROGS_x86_64 += access_tracking_perf_test
 TEST_GEN_PROGS_x86_64 += demand_paging_test
 TEST_GEN_PROGS_x86_64 += dirty_log_test
diff --git a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
new file mode 100644
index 000000000000..8df7143ac17d
--- /dev/null
+++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
@@ -0,0 +1,252 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Basic SEV boot tests.
+ *
+ * Copyright (C) 2021 Advanced Micro Devices
+ */
+#define _GNU_SOURCE /* for program_invocation_short_name */
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+
+#include "kvm_util.h"
+#include "processor.h"
+#include "svm_util.h"
+#include "linux/psp-sev.h"
+#include "sev.h"
+
+#define VCPU_ID			2
+#define PAGE_SIZE		4096
+#define PAGE_STRIDE		32
+
+#define SHARED_PAGES		8192
+#define SHARED_VADDR_MIN	0x1000000
+
+#define PRIVATE_PAGES		2048
+#define PRIVATE_VADDR_MIN	(SHARED_VADDR_MIN + SHARED_PAGES * PAGE_SIZE)
+
+#define TOTAL_PAGES		(512 + SHARED_PAGES + PRIVATE_PAGES)
+
+static void fill_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
+{
+	int i, j;
+
+	for (i = 0; i < pages; i++)
+		for (j = 0; j < PAGE_SIZE; j += stride)
+			buf[i * PAGE_SIZE + j] = val;
+}
+
+static bool check_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
+{
+	int i, j;
+
+	for (i = 0; i < pages; i++)
+		for (j = 0; j < PAGE_SIZE; j += stride)
+			if (buf[i * PAGE_SIZE + j] != val)
+				return false;
+
+	return true;
+}
+
+static void guest_test_start(struct sev_sync_data *sync)
+{
+	/* Initial guest check-in. */
+	sev_guest_sync(sync, 1, 0);
+}
+
+static void check_test_start(struct kvm_vm *vm, struct sev_sync_data *sync)
+{
+	struct kvm_run *run;
+
+	run = vcpu_state(vm, VCPU_ID);
+	vcpu_run(vm, VCPU_ID);
+
+	/* Initial guest check-in. */
+	sev_check_guest_sync(run, sync, 1);
+}
+
+static void
+guest_test_common(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf)
+{
+	bool success;
+
+	/* Initial check-in for common. */
+	sev_guest_sync(sync, 100, 0);
+
+	/* Ensure initial shared pages are intact. */
+	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
+	SEV_GUEST_ASSERT(sync, 103, success);
+
+	/* Ensure initial private pages are intact/encrypted. */
+	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
+	SEV_GUEST_ASSERT(sync, 104, success);
+
+	/* Ensure host userspace can't read newly-written encrypted data. */
+	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
+
+	sev_guest_sync(sync, 200, 0);
+
+	/* Ensure guest can read newly-written shared data from host. */
+	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
+	SEV_GUEST_ASSERT(sync, 201, success);
+
+	/* Ensure host can read newly-written shared data from guest. */
+	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
+
+	sev_guest_sync(sync, 300, 0);
+}
+
+static void
+check_test_common(struct kvm_vm *vm, struct sev_sync_data *sync,
+		  uint8_t *shared_buf, uint8_t *private_buf)
+{
+	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+	bool success;
+
+	/* Initial guest check-in. */
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 100);
+
+	/* Ensure initial private pages are intact/encrypted. */
+	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
+	TEST_ASSERT(!success, "Initial guest memory not encrypted!");
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 200);
+
+	/* Ensure host userspace can't read newly-written encrypted data. */
+	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
+	TEST_ASSERT(!success, "Modified guest memory not encrypted!");
+
+	/* Ensure guest can read newly-written shared data from host. */
+	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_sync(run, sync, 300);
+
+	/* Ensure host can read newly-written shared data from guest. */
+	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
+	TEST_ASSERT(success, "Host can't read shared guest memory!");
+}
+
+static void
+guest_test_done(struct sev_sync_data *sync)
+{
+	sev_guest_done(sync, 10000, 0);
+}
+
+static void
+check_test_done(struct kvm_vm *vm, struct sev_sync_data *sync)
+{
+	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
+
+	vcpu_run(vm, VCPU_ID);
+	sev_check_guest_done(run, sync, 10000);
+}
+
+static void __attribute__((__flatten__))
+guest_sev_code(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf)
+{
+	uint32_t eax, ebx, ecx, edx;
+	uint64_t sev_status;
+
+	guest_test_start(sync);
+
+	/* Check SEV CPUID bit. */
+	eax = 0x8000001f;
+	ecx = 0;
+	cpuid(&eax, &ebx, &ecx, &edx);
+	SEV_GUEST_ASSERT(sync, 2, eax & (1 << 1));
+
+	/* Check SEV MSR bit. */
+	sev_status = rdmsr(MSR_AMD64_SEV);
+	SEV_GUEST_ASSERT(sync, 3, (sev_status & 0x1) == 1);
+
+	guest_test_common(sync, shared_buf, private_buf);
+
+	guest_test_done(sync);
+}
+
+static void
+setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr,
+		  vm_vaddr_t *shared_vaddr, vm_vaddr_t *private_vaddr)
+{
+	struct kvm_vm *vm = sev_get_vm(sev);
+	uint8_t *shared_buf, *private_buf;
+
+	/* Set up VCPU and initial guest kernel. */
+	vm_vcpu_add_default(vm, VCPU_ID, guest_code);
+	kvm_vm_elf_load(vm, program_invocation_name);
+
+	/* Set up shared sync buffer. */
+	*sync_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0);
+
+	/* Set up buffer for reserved shared memory. */
+	*shared_vaddr = vm_vaddr_alloc_shared(vm, SHARED_PAGES * PAGE_SIZE,
+					      SHARED_VADDR_MIN);
+	shared_buf = addr_gva2hva(vm, *shared_vaddr);
+	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
+
+	/* Set up buffer for reserved private memory. */
+	*private_vaddr = vm_vaddr_alloc(vm, PRIVATE_PAGES * PAGE_SIZE,
+					PRIVATE_VADDR_MIN);
+	private_buf = addr_gva2hva(vm, *private_vaddr);
+	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
+}
+
+static void test_sev(void *guest_code, uint64_t policy)
+{
+	vm_vaddr_t sync_vaddr, shared_vaddr, private_vaddr;
+	uint8_t *shared_buf, *private_buf;
+	struct sev_sync_data *sync;
+	uint8_t measurement[512];
+	struct sev_vm *sev;
+	struct kvm_vm *vm;
+	int i;
+
+	sev = sev_vm_create(policy, TOTAL_PAGES);
+	if (!sev)
+		return;
+	vm = sev_get_vm(sev);
+
+	setup_test_common(sev, guest_code, &sync_vaddr, &shared_vaddr, &private_vaddr);
+
+	/* Set up guest params. */
+	vcpu_args_set(vm, VCPU_ID, 4, sync_vaddr, shared_vaddr, private_vaddr);
+
+	sync = addr_gva2hva(vm, sync_vaddr);
+	shared_buf = addr_gva2hva(vm, shared_vaddr);
+	private_buf = addr_gva2hva(vm, private_vaddr);
+
+	/* Allocations/setup done. Encrypt initial guest payload. */
+	sev_vm_launch(sev);
+
+	/* Dump the initial measurement. A test to actually verify it would be nice. */
+	sev_vm_measure(sev, measurement);
+	pr_info("guest measurement: ");
+	for (i = 0; i < 32; ++i)
+		pr_info("%02x", measurement[i]);
+	pr_info("\n");
+
+	sev_vm_launch_finish(sev);
+
+	/* Guest is ready to run. Do the tests. */
+	check_test_start(vm, sync);
+	check_test_common(vm, sync, shared_buf, private_buf);
+	check_test_done(vm, sync);
+
+	sev_vm_free(sev);
+}
+
+int main(int argc, char *argv[])
+{
+	/* SEV tests */
+	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
+	test_sev(guest_sev_code, 0);
+
+	return 0;
+}
-- 
2.25.1

Re: [RFC 07/16] KVM: selftests: add SEV boot tests

[Krish Sadhukhan]

On 10/6/21 1:37 PM, Michael Roth wrote:
> A common aspect of booting SEV guests is checking related CPUID/MSR
> bits and accessing shared/private memory. Add a basic test to cover
> this.
>
> This test will be expanded to cover basic boot of SEV-ES and SEV-SNP in
> subsequent patches.
>
> Signed-off-by: Michael Roth <michael.roth@amd.com>
> ---
>   tools/testing/selftests/kvm/.gitignore        |   1 +
>   tools/testing/selftests/kvm/Makefile          |   1 +
>   .../selftests/kvm/x86_64/sev_all_boot_test.c  | 252 ++++++++++++++++++
>   3 files changed, 254 insertions(+)
>   create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
>
> diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
> index 0709af0144c8..824f100bec2a 100644
> --- a/tools/testing/selftests/kvm/.gitignore
> +++ b/tools/testing/selftests/kvm/.gitignore
> @@ -38,6 +38,7 @@
>   /x86_64/xen_vmcall_test
>   /x86_64/xss_msr_test
>   /x86_64/vmx_pmu_msrs_test
> +/x86_64/sev_all_boot_test
>   /access_tracking_perf_test
>   /demand_paging_test
>   /dirty_log_test
> diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> index c7a5e1c69e0c..aa8901bdbd22 100644
> --- a/tools/testing/selftests/kvm/Makefile
> +++ b/tools/testing/selftests/kvm/Makefile
> @@ -72,6 +72,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/tsc_msrs_test
>   TEST_GEN_PROGS_x86_64 += x86_64/vmx_pmu_msrs_test
>   TEST_GEN_PROGS_x86_64 += x86_64/xen_shinfo_test
>   TEST_GEN_PROGS_x86_64 += x86_64/xen_vmcall_test
> +TEST_GEN_PROGS_x86_64 += x86_64/sev_all_boot_test
>   TEST_GEN_PROGS_x86_64 += access_tracking_perf_test
>   TEST_GEN_PROGS_x86_64 += demand_paging_test
>   TEST_GEN_PROGS_x86_64 += dirty_log_test
> diff --git a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
> new file mode 100644
> index 000000000000..8df7143ac17d
> --- /dev/null
> +++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
> @@ -0,0 +1,252 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Basic SEV boot tests.
> + *
> + * Copyright (C) 2021 Advanced Micro Devices
> + */
> +#define _GNU_SOURCE /* for program_invocation_short_name */
> +#include <fcntl.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <sys/ioctl.h>
> +
> +#include "test_util.h"
> +
> +#include "kvm_util.h"
> +#include "processor.h"
> +#include "svm_util.h"
> +#include "linux/psp-sev.h"
> +#include "sev.h"
> +
> +#define VCPU_ID			2
> +#define PAGE_SIZE		4096
> +#define PAGE_STRIDE		32
> +
> +#define SHARED_PAGES		8192
> +#define SHARED_VADDR_MIN	0x1000000
> +
> +#define PRIVATE_PAGES		2048
> +#define PRIVATE_VADDR_MIN	(SHARED_VADDR_MIN + SHARED_PAGES * PAGE_SIZE)
> +
> +#define TOTAL_PAGES		(512 + SHARED_PAGES + PRIVATE_PAGES)
> +
> +static void fill_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
> +{
> +	int i, j;
> +
> +	for (i = 0; i < pages; i++)
> +		for (j = 0; j < PAGE_SIZE; j += stride)
> +			buf[i * PAGE_SIZE + j] = val;
> +}
> +
> +static bool check_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
> +{
> +	int i, j;
> +
> +	for (i = 0; i < pages; i++)
> +		for (j = 0; j < PAGE_SIZE; j += stride)
> +			if (buf[i * PAGE_SIZE + j] != val)
> +				return false;
> +
> +	return true;
> +}
> +
> +static void guest_test_start(struct sev_sync_data *sync)
> +{
> +	/* Initial guest check-in. */
> +	sev_guest_sync(sync, 1, 0);
> +}
> +
> +static void check_test_start(struct kvm_vm *vm, struct sev_sync_data *sync)
> +{
> +	struct kvm_run *run;
> +
> +	run = vcpu_state(vm, VCPU_ID);
> +	vcpu_run(vm, VCPU_ID);
> +
> +	/* Initial guest check-in. */
> +	sev_check_guest_sync(run, sync, 1);
> +}
> +
> +static void
> +guest_test_common(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf)
> +{
> +	bool success;
> +
> +	/* Initial check-in for common. */
> +	sev_guest_sync(sync, 100, 0);
> +
> +	/* Ensure initial shared pages are intact. */
> +	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
> +	SEV_GUEST_ASSERT(sync, 103, success);
> +
> +	/* Ensure initial private pages are intact/encrypted. */
> +	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
> +	SEV_GUEST_ASSERT(sync, 104, success);
> +
> +	/* Ensure host userspace can't read newly-written encrypted data. */
> +	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
> +
> +	sev_guest_sync(sync, 200, 0);
> +
> +	/* Ensure guest can read newly-written shared data from host. */
> +	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
> +	SEV_GUEST_ASSERT(sync, 201, success);
> +
> +	/* Ensure host can read newly-written shared data from guest. */
> +	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
> +
> +	sev_guest_sync(sync, 300, 0);
> +}
> +
> +static void
> +check_test_common(struct kvm_vm *vm, struct sev_sync_data *sync,
> +		  uint8_t *shared_buf, uint8_t *private_buf)
> +{
> +	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
> +	bool success;
> +
> +	/* Initial guest check-in. */
> +	vcpu_run(vm, VCPU_ID);
> +	sev_check_guest_sync(run, sync, 100);
> +
> +	/* Ensure initial private pages are intact/encrypted. */
> +	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
> +	TEST_ASSERT(!success, "Initial guest memory not encrypted!");
> +
> +	vcpu_run(vm, VCPU_ID);
> +	sev_check_guest_sync(run, sync, 200);
> +
> +	/* Ensure host userspace can't read newly-written encrypted data. */
> +	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
> +	TEST_ASSERT(!success, "Modified guest memory not encrypted!");
> +
> +	/* Ensure guest can read newly-written shared data from host. */
> +	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
> +
> +	vcpu_run(vm, VCPU_ID);
> +	sev_check_guest_sync(run, sync, 300);
> +
> +	/* Ensure host can read newly-written shared data from guest. */
> +	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
> +	TEST_ASSERT(success, "Host can't read shared guest memory!");
> +}
> +
> +static void
> +guest_test_done(struct sev_sync_data *sync)
> +{
> +	sev_guest_done(sync, 10000, 0);
> +}
> +
> +static void
> +check_test_done(struct kvm_vm *vm, struct sev_sync_data *sync)
> +{
> +	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
> +
> +	vcpu_run(vm, VCPU_ID);
> +	sev_check_guest_done(run, sync, 10000);
> +}
> +
> +static void __attribute__((__flatten__))
> +guest_sev_code(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf)
> +{
> +	uint32_t eax, ebx, ecx, edx;
> +	uint64_t sev_status;
> +
> +	guest_test_start(sync);
> +
> +	/* Check SEV CPUID bit. */
> +	eax = 0x8000001f;
> +	ecx = 0;
> +	cpuid(&eax, &ebx, &ecx, &edx);
> +	SEV_GUEST_ASSERT(sync, 2, eax & (1 << 1));
> +
> +	/* Check SEV MSR bit. */
> +	sev_status = rdmsr(MSR_AMD64_SEV);
> +	SEV_GUEST_ASSERT(sync, 3, (sev_status & 0x1) == 1);
> +
Is there any need to do the cpuid and MSR tests every time the guest 
code is executed ?
> +	guest_test_common(sync, shared_buf, private_buf);
> +
> +	guest_test_done(sync);
> +}
> +
> +static void
> +setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr,
> +		  vm_vaddr_t *shared_vaddr, vm_vaddr_t *private_vaddr)
> +{
> +	struct kvm_vm *vm = sev_get_vm(sev);
> +	uint8_t *shared_buf, *private_buf;
> +
> +	/* Set up VCPU and initial guest kernel. */
> +	vm_vcpu_add_default(vm, VCPU_ID, guest_code);
> +	kvm_vm_elf_load(vm, program_invocation_name);
> +
> +	/* Set up shared sync buffer. */
> +	*sync_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0);
> +
> +	/* Set up buffer for reserved shared memory. */
> +	*shared_vaddr = vm_vaddr_alloc_shared(vm, SHARED_PAGES * PAGE_SIZE,
> +					      SHARED_VADDR_MIN);
> +	shared_buf = addr_gva2hva(vm, *shared_vaddr);
> +	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
> +
> +	/* Set up buffer for reserved private memory. */
> +	*private_vaddr = vm_vaddr_alloc(vm, PRIVATE_PAGES * PAGE_SIZE,
> +					PRIVATE_VADDR_MIN);
> +	private_buf = addr_gva2hva(vm, *private_vaddr);
> +	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
> +}
> +
> +static void test_sev(void *guest_code, uint64_t policy)
> +{
> +	vm_vaddr_t sync_vaddr, shared_vaddr, private_vaddr;
> +	uint8_t *shared_buf, *private_buf;
> +	struct sev_sync_data *sync;
> +	uint8_t measurement[512];
> +	struct sev_vm *sev;
> +	struct kvm_vm *vm;
> +	int i;
> +
> +	sev = sev_vm_create(policy, TOTAL_PAGES);
> +	if (!sev)
> +		return;
> +	vm = sev_get_vm(sev);
> +
> +	setup_test_common(sev, guest_code, &sync_vaddr, &shared_vaddr, &private_vaddr);
> +
> +	/* Set up guest params. */
> +	vcpu_args_set(vm, VCPU_ID, 4, sync_vaddr, shared_vaddr, private_vaddr);
> +
> +	sync = addr_gva2hva(vm, sync_vaddr);
> +	shared_buf = addr_gva2hva(vm, shared_vaddr);
> +	private_buf = addr_gva2hva(vm, private_vaddr);
> +
> +	/* Allocations/setup done. Encrypt initial guest payload. */
> +	sev_vm_launch(sev);
> +
> +	/* Dump the initial measurement. A test to actually verify it would be nice. */
> +	sev_vm_measure(sev, measurement);
> +	pr_info("guest measurement: ");
> +	for (i = 0; i < 32; ++i)
> +		pr_info("%02x", measurement[i]);
> +	pr_info("\n");
> +
> +	sev_vm_launch_finish(sev);
Since the above section of this function is actually setup code and is 
not running the test yet, it is best placed in a setup function. My 
suggestion is that you place the above section into a function called 
setup_test_common() and within that function you further separate out 
the SEV-related setup into a function called setup_test_sev() or 
something similar. Then call the top-level setup function from within 
main().
> +
> +	/* Guest is ready to run. Do the tests. */
> +	check_test_start(vm, sync);
> +	check_test_common(vm, sync, shared_buf, private_buf);
> +	check_test_done(vm, sync);

These function names can be better. These functions are not just 
checking the result, they are actually running the guest code. So, may 
be, calling them 'test_start, test_common and test_done are better. I 
would just collapse them and place their code in test_sev() only if you 
separate the out the setup code as I suggested above.

> +
> +	sev_vm_free(sev);
> +}
> +
> +int main(int argc, char *argv[])
> +{
> +	/* SEV tests */
> +	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
> +	test_sev(guest_sev_code, 0);
> +
> +	return 0;
> +}

Re: [RFC 07/16] KVM: selftests: add SEV boot tests

[Michael Roth]

On Fri, Oct 15, 2021 at 07:55:53PM -0700, Krish Sadhukhan wrote:
> 
> On 10/6/21 1:37 PM, Michael Roth wrote:
> > A common aspect of booting SEV guests is checking related CPUID/MSR
> > bits and accessing shared/private memory. Add a basic test to cover
> > this.
> > 
> > This test will be expanded to cover basic boot of SEV-ES and SEV-SNP in
> > subsequent patches.
> > 
> > Signed-off-by: Michael Roth <michael.roth@amd.com>
> > ---
> >   tools/testing/selftests/kvm/.gitignore        |   1 +
> >   tools/testing/selftests/kvm/Makefile          |   1 +
> >   .../selftests/kvm/x86_64/sev_all_boot_test.c  | 252 ++++++++++++++++++
> >   3 files changed, 254 insertions(+)
> >   create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
> > 
> > diff --git a/tools/testing/selftests/kvm/.gitignore b/tools/testing/selftests/kvm/.gitignore
> > index 0709af0144c8..824f100bec2a 100644
> > --- a/tools/testing/selftests/kvm/.gitignore
> > +++ b/tools/testing/selftests/kvm/.gitignore
> > @@ -38,6 +38,7 @@
> >   /x86_64/xen_vmcall_test
> >   /x86_64/xss_msr_test
> >   /x86_64/vmx_pmu_msrs_test
> > +/x86_64/sev_all_boot_test
> >   /access_tracking_perf_test
> >   /demand_paging_test
> >   /dirty_log_test
> > diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
> > index c7a5e1c69e0c..aa8901bdbd22 100644
> > --- a/tools/testing/selftests/kvm/Makefile
> > +++ b/tools/testing/selftests/kvm/Makefile
> > @@ -72,6 +72,7 @@ TEST_GEN_PROGS_x86_64 += x86_64/tsc_msrs_test
> >   TEST_GEN_PROGS_x86_64 += x86_64/vmx_pmu_msrs_test
> >   TEST_GEN_PROGS_x86_64 += x86_64/xen_shinfo_test
> >   TEST_GEN_PROGS_x86_64 += x86_64/xen_vmcall_test
> > +TEST_GEN_PROGS_x86_64 += x86_64/sev_all_boot_test
> >   TEST_GEN_PROGS_x86_64 += access_tracking_perf_test
> >   TEST_GEN_PROGS_x86_64 += demand_paging_test
> >   TEST_GEN_PROGS_x86_64 += dirty_log_test
> > diff --git a/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
> > new file mode 100644
> > index 000000000000..8df7143ac17d
> > --- /dev/null
> > +++ b/tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
> > @@ -0,0 +1,252 @@
> > +// SPDX-License-Identifier: GPL-2.0-only
> > +/*
> > + * Basic SEV boot tests.
> > + *
> > + * Copyright (C) 2021 Advanced Micro Devices
> > + */
> > +#define _GNU_SOURCE /* for program_invocation_short_name */
> > +#include <fcntl.h>
> > +#include <stdio.h>
> > +#include <stdlib.h>
> > +#include <string.h>
> > +#include <sys/ioctl.h>
> > +
> > +#include "test_util.h"
> > +
> > +#include "kvm_util.h"
> > +#include "processor.h"
> > +#include "svm_util.h"
> > +#include "linux/psp-sev.h"
> > +#include "sev.h"
> > +
> > +#define VCPU_ID			2
> > +#define PAGE_SIZE		4096
> > +#define PAGE_STRIDE		32
> > +
> > +#define SHARED_PAGES		8192
> > +#define SHARED_VADDR_MIN	0x1000000
> > +
> > +#define PRIVATE_PAGES		2048
> > +#define PRIVATE_VADDR_MIN	(SHARED_VADDR_MIN + SHARED_PAGES * PAGE_SIZE)
> > +
> > +#define TOTAL_PAGES		(512 + SHARED_PAGES + PRIVATE_PAGES)
> > +
> > +static void fill_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
> > +{
> > +	int i, j;
> > +
> > +	for (i = 0; i < pages; i++)
> > +		for (j = 0; j < PAGE_SIZE; j += stride)
> > +			buf[i * PAGE_SIZE + j] = val;
> > +}
> > +
> > +static bool check_buf(uint8_t *buf, size_t pages, size_t stride, uint8_t val)
> > +{
> > +	int i, j;
> > +
> > +	for (i = 0; i < pages; i++)
> > +		for (j = 0; j < PAGE_SIZE; j += stride)
> > +			if (buf[i * PAGE_SIZE + j] != val)
> > +				return false;
> > +
> > +	return true;
> > +}
> > +
> > +static void guest_test_start(struct sev_sync_data *sync)
> > +{
> > +	/* Initial guest check-in. */
> > +	sev_guest_sync(sync, 1, 0);
> > +}
> > +
> > +static void check_test_start(struct kvm_vm *vm, struct sev_sync_data *sync)
> > +{
> > +	struct kvm_run *run;
> > +
> > +	run = vcpu_state(vm, VCPU_ID);
> > +	vcpu_run(vm, VCPU_ID);
> > +
> > +	/* Initial guest check-in. */
> > +	sev_check_guest_sync(run, sync, 1);
> > +}
> > +
> > +static void
> > +guest_test_common(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf)
> > +{
> > +	bool success;
> > +
> > +	/* Initial check-in for common. */
> > +	sev_guest_sync(sync, 100, 0);
> > +
> > +	/* Ensure initial shared pages are intact. */
> > +	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
> > +	SEV_GUEST_ASSERT(sync, 103, success);
> > +
> > +	/* Ensure initial private pages are intact/encrypted. */
> > +	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
> > +	SEV_GUEST_ASSERT(sync, 104, success);
> > +
> > +	/* Ensure host userspace can't read newly-written encrypted data. */
> > +	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
> > +
> > +	sev_guest_sync(sync, 200, 0);
> > +
> > +	/* Ensure guest can read newly-written shared data from host. */
> > +	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
> > +	SEV_GUEST_ASSERT(sync, 201, success);
> > +
> > +	/* Ensure host can read newly-written shared data from guest. */
> > +	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
> > +
> > +	sev_guest_sync(sync, 300, 0);
> > +}
> > +
> > +static void
> > +check_test_common(struct kvm_vm *vm, struct sev_sync_data *sync,
> > +		  uint8_t *shared_buf, uint8_t *private_buf)
> > +{
> > +	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
> > +	bool success;
> > +
> > +	/* Initial guest check-in. */
> > +	vcpu_run(vm, VCPU_ID);
> > +	sev_check_guest_sync(run, sync, 100);
> > +
> > +	/* Ensure initial private pages are intact/encrypted. */
> > +	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
> > +	TEST_ASSERT(!success, "Initial guest memory not encrypted!");
> > +
> > +	vcpu_run(vm, VCPU_ID);
> > +	sev_check_guest_sync(run, sync, 200);
> > +
> > +	/* Ensure host userspace can't read newly-written encrypted data. */
> > +	success = check_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x43);
> > +	TEST_ASSERT(!success, "Modified guest memory not encrypted!");
> > +
> > +	/* Ensure guest can read newly-written shared data from host. */
> > +	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x44);
> > +
> > +	vcpu_run(vm, VCPU_ID);
> > +	sev_check_guest_sync(run, sync, 300);
> > +
> > +	/* Ensure host can read newly-written shared data from guest. */
> > +	success = check_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x45);
> > +	TEST_ASSERT(success, "Host can't read shared guest memory!");
> > +}
> > +
> > +static void
> > +guest_test_done(struct sev_sync_data *sync)
> > +{
> > +	sev_guest_done(sync, 10000, 0);
> > +}
> > +
> > +static void
> > +check_test_done(struct kvm_vm *vm, struct sev_sync_data *sync)
> > +{
> > +	struct kvm_run *run = vcpu_state(vm, VCPU_ID);
> > +
> > +	vcpu_run(vm, VCPU_ID);
> > +	sev_check_guest_done(run, sync, 10000);
> > +}
> > +
> > +static void __attribute__((__flatten__))
> > +guest_sev_code(struct sev_sync_data *sync, uint8_t *shared_buf, uint8_t *private_buf)
> > +{
> > +	uint32_t eax, ebx, ecx, edx;
> > +	uint64_t sev_status;
> > +
> > +	guest_test_start(sync);
> > +
> > +	/* Check SEV CPUID bit. */
> > +	eax = 0x8000001f;
> > +	ecx = 0;
> > +	cpuid(&eax, &ebx, &ecx, &edx);
> > +	SEV_GUEST_ASSERT(sync, 2, eax & (1 << 1));
> > +
> > +	/* Check SEV MSR bit. */
> > +	sev_status = rdmsr(MSR_AMD64_SEV);
> > +	SEV_GUEST_ASSERT(sync, 3, (sev_status & 0x1) == 1);
> > +
> Is there any need to do the cpuid and MSR tests every time the guest code is
> executed ?

It seems like a good sanity check that KVM is setting the expected bits
(via KVM_GET_SUPPORTED_CPUID) for SEV guests. This is also a fairly
common example of the sort of things a guest would do during boot to
detect/initialize SEV-related functionality.

It becomes a little more useful for the SEV-ES/SEV-SNP tests, where cpuid
instructions cause a #VC exception, which in turn leads to a VMGExit and
exercises the host KVM's handling of host-guest communiction via GHCB
MSR/GHCB page.

> > +	guest_test_common(sync, shared_buf, private_buf);
> > +
> > +	guest_test_done(sync);
> > +}
> > +
> > +static void
> > +setup_test_common(struct sev_vm *sev, void *guest_code, vm_vaddr_t *sync_vaddr,
> > +		  vm_vaddr_t *shared_vaddr, vm_vaddr_t *private_vaddr)
> > +{
> > +	struct kvm_vm *vm = sev_get_vm(sev);
> > +	uint8_t *shared_buf, *private_buf;
> > +
> > +	/* Set up VCPU and initial guest kernel. */
> > +	vm_vcpu_add_default(vm, VCPU_ID, guest_code);
> > +	kvm_vm_elf_load(vm, program_invocation_name);
> > +
> > +	/* Set up shared sync buffer. */
> > +	*sync_vaddr = vm_vaddr_alloc_shared(vm, PAGE_SIZE, 0);
> > +
> > +	/* Set up buffer for reserved shared memory. */
> > +	*shared_vaddr = vm_vaddr_alloc_shared(vm, SHARED_PAGES * PAGE_SIZE,
> > +					      SHARED_VADDR_MIN);
> > +	shared_buf = addr_gva2hva(vm, *shared_vaddr);
> > +	fill_buf(shared_buf, SHARED_PAGES, PAGE_STRIDE, 0x41);
> > +
> > +	/* Set up buffer for reserved private memory. */
> > +	*private_vaddr = vm_vaddr_alloc(vm, PRIVATE_PAGES * PAGE_SIZE,
> > +					PRIVATE_VADDR_MIN);
> > +	private_buf = addr_gva2hva(vm, *private_vaddr);
> > +	fill_buf(private_buf, PRIVATE_PAGES, PAGE_STRIDE, 0x42);
> > +}
> > +
> > +static void test_sev(void *guest_code, uint64_t policy)
> > +{
> > +	vm_vaddr_t sync_vaddr, shared_vaddr, private_vaddr;
> > +	uint8_t *shared_buf, *private_buf;
> > +	struct sev_sync_data *sync;
> > +	uint8_t measurement[512];
> > +	struct sev_vm *sev;
> > +	struct kvm_vm *vm;
> > +	int i;
> > +
> > +	sev = sev_vm_create(policy, TOTAL_PAGES);
> > +	if (!sev)
> > +		return;
> > +	vm = sev_get_vm(sev);
> > +
> > +	setup_test_common(sev, guest_code, &sync_vaddr, &shared_vaddr, &private_vaddr);
> > +
> > +	/* Set up guest params. */
> > +	vcpu_args_set(vm, VCPU_ID, 4, sync_vaddr, shared_vaddr, private_vaddr);
> > +
> > +	sync = addr_gva2hva(vm, sync_vaddr);
> > +	shared_buf = addr_gva2hva(vm, shared_vaddr);
> > +	private_buf = addr_gva2hva(vm, private_vaddr);
> > +
> > +	/* Allocations/setup done. Encrypt initial guest payload. */
> > +	sev_vm_launch(sev);
> > +
> > +	/* Dump the initial measurement. A test to actually verify it would be nice. */
> > +	sev_vm_measure(sev, measurement);
> > +	pr_info("guest measurement: ");
> > +	for (i = 0; i < 32; ++i)
> > +		pr_info("%02x", measurement[i]);
> > +	pr_info("\n");
> > +
> > +	sev_vm_launch_finish(sev);
> Since the above section of this function is actually setup code and is not
> running the test yet, it is best placed in a setup function. My suggestion
> is that you place the above section into a function called
> setup_test_common() and within that function you further separate out the
> SEV-related setup into a function called setup_test_sev() or something
> similar. Then call the top-level setup function from within main().

That makes sense. I'll try to rework this according to your suggestions.

> > +
> > +	/* Guest is ready to run. Do the tests. */
> > +	check_test_start(vm, sync);
> > +	check_test_common(vm, sync, shared_buf, private_buf);
> > +	check_test_done(vm, sync);
> 
> These function names can be better. These functions are not just checking
> the result, they are actually running the guest code. So, may be, calling
> them 'test_start, test_common and test_done are better. I would just

Will do.

> collapse them and place their code in test_sev() only if you separate the
> out the setup code as I suggested above.

Hmm, I did it that way because in the guest_{sev,sev_es,sev_snp}_code
routines there are some type-specific checks that happen before
guest_test_done(), so it made sense to have that in a separate routine,
and seemed more readable to then also have check_test_done() separate to
pair with it. But I'll see if I can rework that a bit.

> 
> > +
> > +	sev_vm_free(sev);
> > +}
> > +
> > +int main(int argc, char *argv[])
> > +{
> > +	/* SEV tests */
> > +	test_sev(guest_sev_code, SEV_POLICY_NO_DBG);
> > +	test_sev(guest_sev_code, 0);
> > +
> > +	return 0;
> > +}

[RFC 08/16] KVM: SVM: include CR3 in initial VMSA state for SEV-ES guests

[Michael Roth]

Normally guests will set up CR3 themselves, but some guests, such as
kselftests, and potentially CONFIG_PVH guests, rely on being booted
with paging enabled and CR3 initialized to a pre-allocated page table.

Currently CR3 updates via KVM_SET_SREGS* are not loaded into the guest
VMCB until just prior to entering the guest. For SEV-ES/SEV-SNP, this
is too late, since it will have switched over to using the VMSA page
prior to that point, with the VMSA CR3 copied from the VMCB initial
CR3 value: 0.

Address this by sync'ing the CR3 value into the VMCB save area
immediately when KVM_SET_SREGS* is issued so it will find it's way into
the initial VMSA.

Suggested-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Michael Roth <michael.roth@amd.com>
---
 arch/x86/include/asm/kvm-x86-ops.h |  1 +
 arch/x86/include/asm/kvm_host.h    |  1 +
 arch/x86/kvm/svm/svm.c             | 22 ++++++++++++++++++++++
 arch/x86/kvm/vmx/vmx.c             |  8 ++++++++
 arch/x86/kvm/x86.c                 |  3 +--
 5 files changed, 33 insertions(+), 2 deletions(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 3d25a86840db..653659e20614 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -35,6 +35,7 @@ KVM_X86_OP(get_cpl)
 KVM_X86_OP(set_segment)
 KVM_X86_OP_NULL(get_cs_db_l_bits)
 KVM_X86_OP(set_cr0)
+KVM_X86_OP(set_cr3)
 KVM_X86_OP(is_valid_cr4)
 KVM_X86_OP(set_cr4)
 KVM_X86_OP(set_efer)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 09ec1ff5bd83..232e997acae6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1324,6 +1324,7 @@ struct kvm_x86_ops {
 			    struct kvm_segment *var, int seg);
 	void (*get_cs_db_l_bits)(struct kvm_vcpu *vcpu, int *db, int *l);
 	void (*set_cr0)(struct kvm_vcpu *vcpu, unsigned long cr0);
+	void (*set_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3);
 	bool (*is_valid_cr4)(struct kvm_vcpu *vcpu, unsigned long cr0);
 	void (*set_cr4)(struct kvm_vcpu *vcpu, unsigned long cr4);
 	int (*set_efer)(struct kvm_vcpu *vcpu, u64 efer);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 7e19f5f6d0d8..2c3bc7a667c8 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1716,6 +1716,27 @@ static void svm_set_gdt(struct kvm_vcpu *vcpu, struct desc_ptr *dt)
 	vmcb_mark_dirty(svm->vmcb, VMCB_DT);
 }
 
+static void svm_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
+{
+	struct vcpu_svm *svm = to_svm(vcpu);
+
+	vcpu->arch.cr3 = cr3;
+	kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
+
+	/*
+	 * For guests that don't set guest_state_protected, the cr3 update is
+	 * handled via kvm_mmu_load() while entering the guest. For guests
+	 * that do (SEV-ES/SEV-SNP), the cr3 update needs to be written to
+	 * VMCB save area now, since the save area will become the initial
+	 * contents of the VMSA, and future VMCB save area updates won't be
+	 * seen.
+	 */
+	if (sev_es_guest(vcpu->kvm)) {
+		svm->vmcb->save.cr3 = cr3;
+		vmcb_mark_dirty(svm->vmcb, VMCB_CR);
+	}
+}
+
 void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -4564,6 +4585,7 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
 	.get_cpl = svm_get_cpl,
 	.get_cs_db_l_bits = kvm_get_cs_db_l_bits,
 	.set_cr0 = svm_set_cr0,
+	.set_cr3 = svm_set_cr3,
 	.is_valid_cr4 = svm_is_valid_cr4,
 	.set_cr4 = svm_set_cr4,
 	.set_efer = svm_set_efer,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index fada1055f325..4f233d0b05bf 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -3130,6 +3130,13 @@ static void vmx_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
 		vmcs_writel(GUEST_CR3, guest_cr3);
 }
 
+
+void vmx_set_cr3(struct kvm_vcpu *vcpu, unsigned long cr3)
+{
+	vcpu->arch.cr3 = cr3;
+	kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
+}
+
 static bool vmx_is_valid_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
 {
 	/*
@@ -7578,6 +7585,7 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
 	.get_cpl = vmx_get_cpl,
 	.get_cs_db_l_bits = vmx_get_cs_db_l_bits,
 	.set_cr0 = vmx_set_cr0,
+	.set_cr3 = vmx_set_cr3,
 	.is_valid_cr4 = vmx_is_valid_cr4,
 	.set_cr4 = vmx_set_cr4,
 	.set_efer = vmx_set_efer,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index c1a2dd0024b2..d724fa185bef 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10400,8 +10400,7 @@ static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs,
 
 	vcpu->arch.cr2 = sregs->cr2;
 	*mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
-	vcpu->arch.cr3 = sregs->cr3;
-	kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
+	static_call(kvm_x86_set_cr3)(vcpu, sregs->cr3);
 
 	kvm_set_cr8(vcpu, sregs->cr8);
 
-- 
2.25.1

Re: [RFC 08/16] KVM: SVM: include CR3 in initial VMSA state for SEV-ES guests

[Paolo Bonzini]

On 06/10/21 22:37, Michael Roth wrote:
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index c1a2dd0024b2..d724fa185bef 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -10400,8 +10400,7 @@ static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs,
>   
>   	vcpu->arch.cr2 = sregs->cr2;
>   	*mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
> -	vcpu->arch.cr3 = sregs->cr3;
> -	kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
> +	static_call(kvm_x86_set_cr3)(vcpu, sregs->cr3);
>   
>   	kvm_set_cr8(vcpu, sregs->cr8);
>   
> 

Can you instead make the hook "post_set_sregs", and keep these two lines 
in __set_sregs_common?

Thanks,

Paolo

Re: [RFC 08/16] KVM: SVM: include CR3 in initial VMSA state for SEV-ES guests

[Michael Roth]

On Thu, Oct 21, 2021 at 06:43:34PM +0200, Paolo Bonzini wrote:
> On 06/10/21 22:37, Michael Roth wrote:
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index c1a2dd0024b2..d724fa185bef 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -10400,8 +10400,7 @@ static int __set_sregs_common(struct kvm_vcpu *vcpu, struct kvm_sregs *sregs,
> >   	vcpu->arch.cr2 = sregs->cr2;
> >   	*mmu_reset_needed |= kvm_read_cr3(vcpu) != sregs->cr3;
> > -	vcpu->arch.cr3 = sregs->cr3;
> > -	kvm_register_mark_available(vcpu, VCPU_EXREG_CR3);
> > +	static_call(kvm_x86_set_cr3)(vcpu, sregs->cr3);
> >   	kvm_set_cr8(vcpu, sregs->cr8);
> > 
> 
> Can you instead make the hook "post_set_sregs", and keep these two lines in
> __set_sregs_common?

Makes sense. Will do.

> 
> Thanks,
> 
> Paolo
> 

Re: [RFC 00/16] KVM: selftests: Add tests for SEV, SEV-ES, and SEV-SNP guests

[Paolo Bonzini]

On 06/10/21 01:44, Michael Roth wrote:
> These patches and are also available at:
> 
>    https://github.com/mdroth/linux/commits/sev-selftests-rfc1
> 
> They are based on top of v5 of Brijesh's SEV-SNP hypervisor patches[1]
> to allow for SEV-SNP testing and provide some context for the overall
> design, but the SEV/SEV-ES patches can be carved out into a separate
> series as needed.
> 
> == OVERVIEW ==
> 
> This series introduces a set of memory encryption-related parameter/hooks
> in the core kselftest library, then uses the hooks to implement a small
> library for creating/managing SEV, SEV-ES, SEV-SNP guests. This library
> is then used to implement a basic boot/memory test that's run for all
> variants of SEV/SEV-ES/SEV-SNP guest types, as well as a set of SEV-SNP
> tests that cover various permutations of pvalidate/page-state changes.
> 
> - Patches 1-7 implement SEV boot tests and should run against existing
>    kernels
> - Patch 8 is a KVM changes that's required to allow SEV-ES/SEV-SNP
>    guests to boot with an externally generated page table, and is a
>    host kernel prequisite for the remaining patches in the series.
> - Patches 9-12 extend the boot tests to cover SEV-ES
> - Patches 13-16 extend the boot testst to cover SEV-SNP, and introduce
>    an additional test for page-state changes.

Hi Mike,

this SEV/SEV-ES testing (both your series and kvm-unit-tests) is good 
stuff. :)  If you fix up patches 1-12, I will commit them pretty much 
straight away.  The only thing that possibly needs some thought is the 
integration with ucall.

Thanks,

Paolo

> Any review/comments are greatly appreciated!
> 
> [1] https://lore.kernel.org/linux-mm/20210820155918.7518-1-brijesh.singh@amd.com/
> 
> ----------------------------------------------------------------
> Michael Roth (16):
>        KVM: selftests: move vm_phy_pages_alloc() earlier in file
>        KVM: selftests: add hooks for managing encrypted guest memory
>        KVM: selftests: handle encryption bits in page tables
>        KVM: selftests: set CPUID before setting sregs in vcpu creation
>        KVM: selftests: add support for encrypted vm_vaddr_* allocations
>        KVM: selftests: add library for creating/interacting with SEV guests
>        KVM: selftests: add SEV boot tests
>        KVM: SVM: include CR3 in initial VMSA state for SEV-ES guests
>        KVM: selftests: account for error code in #VC exception frame
>        KVM: selftests: add support for creating SEV-ES guests
>        KVM: selftests: add library for handling SEV-ES-related exits
>        KVM: selftests: add SEV-ES boot tests
>        KVM: selftests: add support for creating SEV-SNP guests
>        KVM: selftests: add helpers for SEV-SNP-related instructions/exits
>        KVM: selftests: add SEV-SNP boot tests
>        KVM: selftests: add SEV-SNP tests for page-state changes
> 
>   arch/x86/include/asm/kvm-x86-ops.h                 |   1 +
>   arch/x86/include/asm/kvm_host.h                    |   1 +
>   arch/x86/kvm/svm/svm.c                             |  22 ++
>   arch/x86/kvm/vmx/vmx.c                             |   8 +
>   arch/x86/kvm/x86.c                                 |   3 +-
>   tools/testing/selftests/kvm/.gitignore             |   2 +
>   tools/testing/selftests/kvm/Makefile               |   3 +
>   tools/testing/selftests/kvm/include/kvm_util.h     |   8 +
>   tools/testing/selftests/kvm/include/x86_64/sev.h   |  70 ++++
>   .../selftests/kvm/include/x86_64/sev_exitlib.h     |  20 ++
>   tools/testing/selftests/kvm/include/x86_64/svm.h   |  35 ++
>   .../selftests/kvm/include/x86_64/svm_util.h        |   2 +
>   tools/testing/selftests/kvm/lib/kvm_util.c         | 249 +++++++++-----
>   .../testing/selftests/kvm/lib/kvm_util_internal.h  |  10 +
>   tools/testing/selftests/kvm/lib/x86_64/handlers.S  |   4 +-
>   tools/testing/selftests/kvm/lib/x86_64/processor.c |  30 +-
>   tools/testing/selftests/kvm/lib/x86_64/sev.c       | 381 +++++++++++++++++++++
>   .../testing/selftests/kvm/lib/x86_64/sev_exitlib.c | 326 ++++++++++++++++++
>   .../selftests/kvm/x86_64/sev_all_boot_test.c       | 367 ++++++++++++++++++++
>   .../selftests/kvm/x86_64/sev_snp_psc_test.c        | 378 ++++++++++++++++++++
>   20 files changed, 1820 insertions(+), 100 deletions(-)
>   create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
>   create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
>   create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
>   create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
>   create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
>   create mode 100644 tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c
> 
> 
> 

Re: [RFC 00/16] KVM: selftests: Add tests for SEV, SEV-ES, and SEV-SNP guests

[Michael Roth]

On Thu, Oct 21, 2021 at 06:48:24PM +0200, Paolo Bonzini wrote:
> On 06/10/21 01:44, Michael Roth wrote:
> > These patches and are also available at:
> > 
> >    https://github.com/mdroth/linux/commits/sev-selftests-rfc1
> > 
> > They are based on top of v5 of Brijesh's SEV-SNP hypervisor patches[1]
> > to allow for SEV-SNP testing and provide some context for the overall
> > design, but the SEV/SEV-ES patches can be carved out into a separate
> > series as needed.
> > 
> > == OVERVIEW ==
> > 
> > This series introduces a set of memory encryption-related parameter/hooks
> > in the core kselftest library, then uses the hooks to implement a small
> > library for creating/managing SEV, SEV-ES, SEV-SNP guests. This library
> > is then used to implement a basic boot/memory test that's run for all
> > variants of SEV/SEV-ES/SEV-SNP guest types, as well as a set of SEV-SNP
> > tests that cover various permutations of pvalidate/page-state changes.
> > 
> > - Patches 1-7 implement SEV boot tests and should run against existing
> >    kernels
> > - Patch 8 is a KVM changes that's required to allow SEV-ES/SEV-SNP
> >    guests to boot with an externally generated page table, and is a
> >    host kernel prequisite for the remaining patches in the series.
> > - Patches 9-12 extend the boot tests to cover SEV-ES
> > - Patches 13-16 extend the boot testst to cover SEV-SNP, and introduce
> >    an additional test for page-state changes.
> 
> Hi Mike,
> 
> this SEV/SEV-ES testing (both your series and kvm-unit-tests) is good stuff.
> :)  If you fix up patches 1-12, I will commit them pretty much straight
> away.  The only thing that possibly needs some thought is the integration
> with ucall.

Hi Paolo,

Glad to hear :) For v2 I'll work on getting SEV/SEV-ES broken out into a
separate series with all the review comments addressed. Still a little
unsure about the best way to address some things in patch #3, but
outlined a tentative plan that hopefully seems reasonable. Can re-visit
in v2 as well.

Thanks!

-Mike

> 
> Thanks,
> 
> Paolo
> 
> > Any review/comments are greatly appreciated!
> > 
> > [1] https://lore.kernel.org/linux-mm/20210820155918.7518-1-brijesh.singh@amd.com/
> > 
> > ----------------------------------------------------------------
> > Michael Roth (16):
> >        KVM: selftests: move vm_phy_pages_alloc() earlier in file
> >        KVM: selftests: add hooks for managing encrypted guest memory
> >        KVM: selftests: handle encryption bits in page tables
> >        KVM: selftests: set CPUID before setting sregs in vcpu creation
> >        KVM: selftests: add support for encrypted vm_vaddr_* allocations
> >        KVM: selftests: add library for creating/interacting with SEV guests
> >        KVM: selftests: add SEV boot tests
> >        KVM: SVM: include CR3 in initial VMSA state for SEV-ES guests
> >        KVM: selftests: account for error code in #VC exception frame
> >        KVM: selftests: add support for creating SEV-ES guests
> >        KVM: selftests: add library for handling SEV-ES-related exits
> >        KVM: selftests: add SEV-ES boot tests
> >        KVM: selftests: add support for creating SEV-SNP guests
> >        KVM: selftests: add helpers for SEV-SNP-related instructions/exits
> >        KVM: selftests: add SEV-SNP boot tests
> >        KVM: selftests: add SEV-SNP tests for page-state changes
> > 
> >   arch/x86/include/asm/kvm-x86-ops.h                 |   1 +
> >   arch/x86/include/asm/kvm_host.h                    |   1 +
> >   arch/x86/kvm/svm/svm.c                             |  22 ++
> >   arch/x86/kvm/vmx/vmx.c                             |   8 +
> >   arch/x86/kvm/x86.c                                 |   3 +-
> >   tools/testing/selftests/kvm/.gitignore             |   2 +
> >   tools/testing/selftests/kvm/Makefile               |   3 +
> >   tools/testing/selftests/kvm/include/kvm_util.h     |   8 +
> >   tools/testing/selftests/kvm/include/x86_64/sev.h   |  70 ++++
> >   .../selftests/kvm/include/x86_64/sev_exitlib.h     |  20 ++
> >   tools/testing/selftests/kvm/include/x86_64/svm.h   |  35 ++
> >   .../selftests/kvm/include/x86_64/svm_util.h        |   2 +
> >   tools/testing/selftests/kvm/lib/kvm_util.c         | 249 +++++++++-----
> >   .../testing/selftests/kvm/lib/kvm_util_internal.h  |  10 +
> >   tools/testing/selftests/kvm/lib/x86_64/handlers.S  |   4 +-
> >   tools/testing/selftests/kvm/lib/x86_64/processor.c |  30 +-
> >   tools/testing/selftests/kvm/lib/x86_64/sev.c       | 381 +++++++++++++++++++++
> >   .../testing/selftests/kvm/lib/x86_64/sev_exitlib.c | 326 ++++++++++++++++++
> >   .../selftests/kvm/x86_64/sev_all_boot_test.c       | 367 ++++++++++++++++++++
> >   .../selftests/kvm/x86_64/sev_snp_psc_test.c        | 378 ++++++++++++++++++++
> >   20 files changed, 1820 insertions(+), 100 deletions(-)
> >   create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev.h
> >   create mode 100644 tools/testing/selftests/kvm/include/x86_64/sev_exitlib.h
> >   create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev.c
> >   create mode 100644 tools/testing/selftests/kvm/lib/x86_64/sev_exitlib.c
> >   create mode 100644 tools/testing/selftests/kvm/x86_64/sev_all_boot_test.c
> >   create mode 100644 tools/testing/selftests/kvm/x86_64/sev_snp_psc_test.c
> > 
> > 
> > 
> 

Re: [RFC 00/16] KVM: selftests: Add tests for SEV, SEV-ES, and SEV-SNP guests

[Paolo Bonzini]

On 25/10/21 06:27, Michael Roth wrote:
> 
> Glad to hear:)  For v2 I'll work on getting SEV/SEV-ES broken out into a
> separate series with all the review comments addressed. Still a little
> unsure about the best way to address some things in patch #3, but
> outlined a tentative plan that hopefully seems reasonable. Can re-visit
> in v2 as well.

Sounds good, all I can do is point out things that seem "weird", but 
nothing beats the experience of actually working with the code.

Paolo