[PATCH v3 0/4] KVM: selftests: Introduce VM_MODE_PXXV48_4K

[PATCH v3 0/4] KVM: selftests: Introduce VM_MODE_PXXV48_4K

[Peter Xu]

v3:
- pick r-b
- refine DEBUG macro [Drew]

v2:
- pick r-bs
- rebased to master
- fix pa width detect, check cpuid(1):edx.PAE(bit 6)
- fix arm compilation issue [Drew]
- fix indents issues and ways to define macros [Drew]
- provide functions for fetching cpu pa/va bits [Drew]

This series originates from "[PATCH] KVM: selftests: Detect max PA
width from cpuid" [1] and one of Drew's comments - instead of keeping
the hackish line to overwrite guest_pa_bits all the time, this series
introduced the new mode VM_MODE_PXXV48_4K for x86_64 platform.

The major issue is that even all the x86_64 kvm selftests are
currently using the guest mode VM_MODE_P52V48_4K, many x86_64 hosts
are not using 52 bits PA (and in most cases, far less).  If with luck
we could be having 48 bits hosts, but it's more adhoc (I've observed 3
x86_64 systems, they are having different PA width of 36, 39, 48).  I
am not sure whether this is happening to the other archs as well, but
it probably makes sense to bring the x86_64 tests to the real world on
always using the correct PA bits.

A side effect of this series is that it will also fix the crash we've
encountered on Xeon E3-1220 as mentioned [1] due to the
differenciation of PA width.

With [1], we've observed AMD host issues when with NPT=off.  However a
funny fact is that after I reworked into this series, the tests can
instead pass on both NPT=on/off.  It could be that the series changes
vm->pa_bits or other fields so something was affected.  I didn't dig
more on that though, considering we should not lose anything.

[1] https://lkml.org/lkml/2019/8/26/141

Peter Xu (4):
  KVM: selftests: Move vm type into _vm_create() internally
  KVM: selftests: Create VM earlier for dirty log test
  KVM: selftests: Introduce VM_MODE_PXXV48_4K
  KVM: selftests: Remove duplicate guest mode handling

 tools/testing/selftests/kvm/dirty_log_test.c  | 79 +++++--------------
 .../testing/selftests/kvm/include/kvm_util.h  | 18 ++++-
 .../selftests/kvm/include/x86_64/processor.h  |  3 +
 .../selftests/kvm/lib/aarch64/processor.c     |  3 +
 tools/testing/selftests/kvm/lib/kvm_util.c    | 67 ++++++++++++----
 .../selftests/kvm/lib/x86_64/processor.c      | 30 ++++++-
 6 files changed, 121 insertions(+), 79 deletions(-)

-- 
2.21.0

[PATCH v3 1/4] KVM: selftests: Move vm type into _vm_create() internally

[Peter Xu]

Rather than passing the vm type from the top level to the end of vm
creation, let's simply keep that as an internal of kvm_vm struct and
decide the type in _vm_create().  Several reasons for doing this:

- The vm type is only decided by physical address width and currently
  only used in aarch64, so we've got enough information as long as
  we're passing vm_guest_mode into _vm_create(),

- This removes a loop dependency between the vm->type and creation of
  vms.  That's why now we need to parse vm_guest_mode twice sometimes,
  once in run_test() and then again in _vm_create().  The follow up
  patches will move on to clean up that as well so we can have a
  single place to decide guest machine types and so.

Note that this patch will slightly change the behavior of aarch64
tests in that previously most vm_create() callers will directly pass
in type==0 into _vm_create() but now the type will depend on
vm_guest_mode, however it shouldn't affect any user because all
vm_create() users of aarch64 will be using VM_MODE_DEFAULT guest
mode (which is VM_MODE_P40V48_4K) so at last type will still be zero.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 tools/testing/selftests/kvm/dirty_log_test.c  | 13 +++---------
 .../testing/selftests/kvm/include/kvm_util.h  |  3 +--
 tools/testing/selftests/kvm/lib/kvm_util.c    | 21 ++++++++++++-------
 3 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index ceb52b952637..135cba5c6d0d 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -216,14 +216,12 @@ static void vm_dirty_log_verify(unsigned long *bmap)
 }
 
 static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid,
-				uint64_t extra_mem_pages, void *guest_code,
-				unsigned long type)
+				uint64_t extra_mem_pages, void *guest_code)
 {
 	struct kvm_vm *vm;
 	uint64_t extra_pg_pages = extra_mem_pages / 512 * 2;
 
-	vm = _vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages,
-			O_RDWR, type);
+	vm = _vm_create(mode, DEFAULT_GUEST_PHY_PAGES + extra_pg_pages, O_RDWR);
 	kvm_vm_elf_load(vm, program_invocation_name, 0, 0);
 #ifdef __x86_64__
 	vm_create_irqchip(vm);
@@ -240,7 +238,6 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	struct kvm_vm *vm;
 	uint64_t max_gfn;
 	unsigned long *bmap;
-	unsigned long type = 0;
 
 	switch (mode) {
 	case VM_MODE_P52V48_4K:
@@ -281,10 +278,6 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	 * bits we can change to 39.
 	 */
 	guest_pa_bits = 39;
-#endif
-#ifdef __aarch64__
-	if (guest_pa_bits != 40)
-		type = KVM_VM_TYPE_ARM_IPA_SIZE(guest_pa_bits);
 #endif
 	max_gfn = (1ul << (guest_pa_bits - guest_page_shift)) - 1;
 	guest_page_size = (1ul << guest_page_shift);
@@ -309,7 +302,7 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	bmap = bitmap_alloc(host_num_pages);
 	host_bmap_track = bitmap_alloc(host_num_pages);
 
-	vm = create_vm(mode, VCPU_ID, guest_num_pages, guest_code, type);
+	vm = create_vm(mode, VCPU_ID, guest_num_pages, guest_code);
 
 #ifdef USE_CLEAR_DIRTY_LOG
 	struct kvm_enable_cap cap = {};
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index e0e66b115ef2..c78faa2ff7f3 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -60,8 +60,7 @@ int kvm_check_cap(long cap);
 int vm_enable_cap(struct kvm_vm *vm, struct kvm_enable_cap *cap);
 
 struct kvm_vm *vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm);
-struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
-			  int perm, unsigned long type);
+struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm);
 void kvm_vm_free(struct kvm_vm *vmp);
 void kvm_vm_restart(struct kvm_vm *vmp, int perm);
 void kvm_vm_release(struct kvm_vm *vmp);
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 6e49bb039376..34a8a6572c7c 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -84,7 +84,7 @@ int vm_enable_cap(struct kvm_vm *vm, struct kvm_enable_cap *cap)
 	return ret;
 }
 
-static void vm_open(struct kvm_vm *vm, int perm, unsigned long type)
+static void vm_open(struct kvm_vm *vm, int perm)
 {
 	vm->kvm_fd = open(KVM_DEV_PATH, perm);
 	if (vm->kvm_fd < 0)
@@ -95,7 +95,7 @@ static void vm_open(struct kvm_vm *vm, int perm, unsigned long type)
 		exit(KSFT_SKIP);
 	}
 
-	vm->fd = ioctl(vm->kvm_fd, KVM_CREATE_VM, type);
+	vm->fd = ioctl(vm->kvm_fd, KVM_CREATE_VM, vm->type);
 	TEST_ASSERT(vm->fd >= 0, "KVM_CREATE_VM ioctl failed, "
 		"rc: %i errno: %i", vm->fd, errno);
 }
@@ -130,8 +130,7 @@ _Static_assert(sizeof(vm_guest_mode_string)/sizeof(char *) == NUM_VM_MODES,
  * descriptor to control the created VM is created with the permissions
  * given by perm (e.g. O_RDWR).
  */
-struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
-			  int perm, unsigned long type)
+struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
 {
 	struct kvm_vm *vm;
 
@@ -139,8 +138,7 @@ struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
 	TEST_ASSERT(vm != NULL, "Insufficient Memory");
 
 	vm->mode = mode;
-	vm->type = type;
-	vm_open(vm, perm, type);
+	vm->type = 0;
 
 	/* Setup mode specific traits. */
 	switch (vm->mode) {
@@ -190,6 +188,13 @@ struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
 		TEST_ASSERT(false, "Unknown guest mode, mode: 0x%x", mode);
 	}
 
+#ifdef __aarch64__
+	if (vm->pa_bits != 40)
+		vm->type = KVM_VM_TYPE_ARM_IPA_SIZE(vm->pa_bits);
+#endif
+
+	vm_open(vm, perm);
+
 	/* Limit to VA-bit canonical virtual addresses. */
 	vm->vpages_valid = sparsebit_alloc();
 	sparsebit_set_num(vm->vpages_valid,
@@ -212,7 +217,7 @@ struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages,
 
 struct kvm_vm *vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
 {
-	return _vm_create(mode, phy_pages, perm, 0);
+	return _vm_create(mode, phy_pages, perm);
 }
 
 /*
@@ -232,7 +237,7 @@ void kvm_vm_restart(struct kvm_vm *vmp, int perm)
 {
 	struct userspace_mem_region *region;
 
-	vm_open(vmp, perm, vmp->type);
+	vm_open(vmp, perm);
 	if (vmp->has_irqchip)
 		vm_create_irqchip(vmp);
 
-- 
2.21.0

[PATCH v3 2/4] KVM: selftests: Create VM earlier for dirty log test

[Peter Xu]

Since we've just removed the dependency of vm type in previous patch,
now we can create the vm much earlier.  Note that to move it earlier
we used an approximation of number of extra pages but it should be
fine.

This prepares for the follow up patches to finally remove the
duplication of guest mode parsings.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 tools/testing/selftests/kvm/dirty_log_test.c | 19 ++++++++++++++++---
 1 file changed, 16 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index 135cba5c6d0d..efb7746a7e99 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -230,6 +230,9 @@ static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid,
 	return vm;
 }
 
+#define DIRTY_MEM_BITS 30 /* 1G */
+#define PAGE_SHIFT_4K  12
+
 static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 		     unsigned long interval, uint64_t phys_offset)
 {
@@ -239,6 +242,18 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	uint64_t max_gfn;
 	unsigned long *bmap;
 
+	/*
+	 * We reserve page table for 2 times of extra dirty mem which
+	 * will definitely cover the original (1G+) test range.  Here
+	 * we do the calculation with 4K page size which is the
+	 * smallest so the page number will be enough for all archs
+	 * (e.g., 64K page size guest will need even less memory for
+	 * page tables).
+	 */
+	vm = create_vm(mode, VCPU_ID,
+		       2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K),
+		       guest_code);
+
 	switch (mode) {
 	case VM_MODE_P52V48_4K:
 		guest_pa_bits = 52;
@@ -285,7 +300,7 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	 * A little more than 1G of guest page sized pages.  Cover the
 	 * case where the size is not aligned to 64 pages.
 	 */
-	guest_num_pages = (1ul << (30 - guest_page_shift)) + 16;
+	guest_num_pages = (1ul << (DIRTY_MEM_BITS - guest_page_shift)) + 16;
 	host_page_size = getpagesize();
 	host_num_pages = (guest_num_pages * guest_page_size) / host_page_size +
 			 !!((guest_num_pages * guest_page_size) % host_page_size);
@@ -302,8 +317,6 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	bmap = bitmap_alloc(host_num_pages);
 	host_bmap_track = bitmap_alloc(host_num_pages);
 
-	vm = create_vm(mode, VCPU_ID, guest_num_pages, guest_code);
-
 #ifdef USE_CLEAR_DIRTY_LOG
 	struct kvm_enable_cap cap = {};
 
-- 
2.21.0

[PATCH v3 3/4] KVM: selftests: Introduce VM_MODE_PXXV48_4K

[Peter Xu]

The naming VM_MODE_P52V48_4K is explicit but unclear when used on
x86_64 machines, because x86_64 machines are having various physical
address width rather than some static values.  Here's some examples:

  - Intel Xeon E3-1220:  36 bits
  - Intel Core i7-8650:  39 bits
  - AMD   EPYC 7251:     48 bits

All of them are using 48 bits linear address width but with totally
different physical address width (and most of the old machines should
be less than 52 bits).

Let's create a new guest mode called VM_MODE_PXXV48_4K for current
x86_64 tests and make it as the default to replace the old naming of
VM_MODE_P52V48_4K because it shows more clearly that the PA width is
not really a constant.  Meanwhile we also stop assuming all the x86
machines are having 52 bits PA width but instead we fetch the real
vm->pa_bits from CPUID 0x80000008 during runtime.

We currently make this exclusively used by x86_64 but no other arch.

As a slight touch up, moving DEBUG macro from dirty_log_test.c to
kvm_util.h so lib can use it too.

Signed-off-by: Peter Xu <peterx@redhat.com>
---
 tools/testing/selftests/kvm/dirty_log_test.c  |  5 ++--
 .../testing/selftests/kvm/include/kvm_util.h  | 11 ++++++-
 .../selftests/kvm/include/x86_64/processor.h  |  3 ++
 .../selftests/kvm/lib/aarch64/processor.c     |  3 ++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 29 ++++++++++++++----
 .../selftests/kvm/lib/x86_64/processor.c      | 30 ++++++++++++++++---
 6 files changed, 67 insertions(+), 14 deletions(-)

diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index efb7746a7e99..c86f83cb33e5 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -19,8 +19,6 @@
 #include "kvm_util.h"
 #include "processor.h"
 
-#define DEBUG printf
-
 #define VCPU_ID				1
 
 /* The memory slot index to track dirty pages */
@@ -256,6 +254,7 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 
 	switch (mode) {
 	case VM_MODE_P52V48_4K:
+	case VM_MODE_PXXV48_4K:
 		guest_pa_bits = 52;
 		guest_page_shift = 12;
 		break;
@@ -446,7 +445,7 @@ int main(int argc, char *argv[])
 #endif
 
 #ifdef __x86_64__
-	vm_guest_mode_params_init(VM_MODE_P52V48_4K, true, true);
+	vm_guest_mode_params_init(VM_MODE_PXXV48_4K, true, true);
 #endif
 #ifdef __aarch64__
 	vm_guest_mode_params_init(VM_MODE_P40V48_4K, true, true);
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index c78faa2ff7f3..8c71ec886aab 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -24,6 +24,12 @@ struct kvm_vm;
 typedef uint64_t vm_paddr_t; /* Virtual Machine (Guest) physical address */
 typedef uint64_t vm_vaddr_t; /* Virtual Machine (Guest) virtual address */
 
+#ifndef NDEBUG
+#define DEBUG(...) printf(__VA_ARGS__);
+#else
+#define DEBUG(...)
+#endif
+
 /* Minimum allocated guest virtual and physical addresses */
 #define KVM_UTIL_MIN_VADDR		0x2000
 
@@ -38,11 +44,14 @@ enum vm_guest_mode {
 	VM_MODE_P48V48_64K,
 	VM_MODE_P40V48_4K,
 	VM_MODE_P40V48_64K,
+	VM_MODE_PXXV48_4K,	/* For 48bits VA but ANY bits PA */
 	NUM_VM_MODES,
 };
 
-#ifdef __aarch64__
+#if defined(__aarch64__)
 #define VM_MODE_DEFAULT VM_MODE_P40V48_4K
+#elif defined(__x86_64__)
+#define VM_MODE_DEFAULT VM_MODE_PXXV48_4K
 #else
 #define VM_MODE_DEFAULT VM_MODE_P52V48_4K
 #endif
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index 80d19740d2dc..0c17f2ee685e 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -325,6 +325,9 @@ uint64_t vcpu_get_msr(struct kvm_vm *vm, uint32_t vcpuid, uint64_t msr_index);
 void vcpu_set_msr(struct kvm_vm *vm, uint32_t vcpuid, uint64_t msr_index,
 	  	  uint64_t msr_value);
 
+uint32_t kvm_get_cpuid_max(void);
+void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits);
+
 /*
  * Basic CPU control in CR0
  */
diff --git a/tools/testing/selftests/kvm/lib/aarch64/processor.c b/tools/testing/selftests/kvm/lib/aarch64/processor.c
index 486400a97374..86036a59a668 100644
--- a/tools/testing/selftests/kvm/lib/aarch64/processor.c
+++ b/tools/testing/selftests/kvm/lib/aarch64/processor.c
@@ -264,6 +264,9 @@ void aarch64_vcpu_setup(struct kvm_vm *vm, int vcpuid, struct kvm_vcpu_init *ini
 	case VM_MODE_P52V48_4K:
 		TEST_ASSERT(false, "AArch64 does not support 4K sized pages "
 				   "with 52-bit physical address ranges");
+	case VM_MODE_PXXV48_4K:
+		TEST_ASSERT(false, "AArch64 does not support 4K sized pages "
+				   "with ANY-bit physical address ranges");
 	case VM_MODE_P52V48_64K:
 		tcr_el1 |= 1ul << 14; /* TG0 = 64KB */
 		tcr_el1 |= 6ul << 32; /* IPS = 52 bits */
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index 34a8a6572c7c..bb8f993b25fb 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -8,6 +8,7 @@
 #include "test_util.h"
 #include "kvm_util.h"
 #include "kvm_util_internal.h"
+#include "processor.h"
 
 #include <assert.h>
 #include <sys/mman.h>
@@ -101,12 +102,13 @@ static void vm_open(struct kvm_vm *vm, int perm)
 }
 
 const char * const vm_guest_mode_string[] = {
-	"PA-bits:52, VA-bits:48, 4K pages",
-	"PA-bits:52, VA-bits:48, 64K pages",
-	"PA-bits:48, VA-bits:48, 4K pages",
-	"PA-bits:48, VA-bits:48, 64K pages",
-	"PA-bits:40, VA-bits:48, 4K pages",
-	"PA-bits:40, VA-bits:48, 64K pages",
+	"PA-bits:52,  VA-bits:48,  4K pages",
+	"PA-bits:52,  VA-bits:48, 64K pages",
+	"PA-bits:48,  VA-bits:48,  4K pages",
+	"PA-bits:48,  VA-bits:48, 64K pages",
+	"PA-bits:40,  VA-bits:48,  4K pages",
+	"PA-bits:40,  VA-bits:48, 64K pages",
+	"PA-bits:ANY, VA-bits:48,  4K pages",
 };
 _Static_assert(sizeof(vm_guest_mode_string)/sizeof(char *) == NUM_VM_MODES,
 	       "Missing new mode strings?");
@@ -184,6 +186,21 @@ struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
 		vm->page_size = 0x10000;
 		vm->page_shift = 16;
 		break;
+	case VM_MODE_PXXV48_4K:
+#ifdef __x86_64__
+		kvm_get_cpu_address_width(&vm->pa_bits, &vm->va_bits);
+		TEST_ASSERT(vm->va_bits == 48, "Linear address width "
+			    "(%d bits) not supported", vm->va_bits);
+		vm->pgtable_levels = 4;
+		vm->page_size = 0x1000;
+		vm->page_shift = 12;
+		DEBUG("Guest physical address width detected: %d\n",
+		      vm->pa_bits);
+#else
+		TEST_ASSERT(false, "VM_MODE_PXXV48_4K not supported on "
+			    "non-x86 platforms");
+#endif
+		break;
 	default:
 		TEST_ASSERT(false, "Unknown guest mode, mode: 0x%x", mode);
 	}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/processor.c b/tools/testing/selftests/kvm/lib/x86_64/processor.c
index 6cb34a0fa200..48467210ccfc 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/processor.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/processor.c
@@ -228,7 +228,7 @@ void sregs_dump(FILE *stream, struct kvm_sregs *sregs,
 
 void virt_pgd_alloc(struct kvm_vm *vm, uint32_t pgd_memslot)
 {
-	TEST_ASSERT(vm->mode == VM_MODE_P52V48_4K, "Attempt to use "
+	TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K, "Attempt to use "
 		"unknown or unsupported guest mode, mode: 0x%x", vm->mode);
 
 	/* If needed, create page map l4 table. */
@@ -261,7 +261,7 @@ void virt_pg_map(struct kvm_vm *vm, uint64_t vaddr, uint64_t paddr,
 	uint16_t index[4];
 	struct pageMapL4Entry *pml4e;
 
-	TEST_ASSERT(vm->mode == VM_MODE_P52V48_4K, "Attempt to use "
+	TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K, "Attempt to use "
 		"unknown or unsupported guest mode, mode: 0x%x", vm->mode);
 
 	TEST_ASSERT((vaddr % vm->page_size) == 0,
@@ -547,7 +547,7 @@ vm_paddr_t addr_gva2gpa(struct kvm_vm *vm, vm_vaddr_t gva)
 	struct pageDirectoryEntry *pde;
 	struct pageTableEntry *pte;
 
-	TEST_ASSERT(vm->mode == VM_MODE_P52V48_4K, "Attempt to use "
+	TEST_ASSERT(vm->mode == VM_MODE_PXXV48_4K, "Attempt to use "
 		"unknown or unsupported guest mode, mode: 0x%x", vm->mode);
 
 	index[0] = (gva >> 12) & 0x1ffu;
@@ -621,7 +621,7 @@ static void vcpu_setup(struct kvm_vm *vm, int vcpuid, int pgd_memslot, int gdt_m
 	kvm_setup_gdt(vm, &sregs.gdt, gdt_memslot, pgd_memslot);
 
 	switch (vm->mode) {
-	case VM_MODE_P52V48_4K:
+	case VM_MODE_PXXV48_4K:
 		sregs.cr0 = X86_CR0_PE | X86_CR0_NE | X86_CR0_PG;
 		sregs.cr4 |= X86_CR4_PAE | X86_CR4_OSFXSR;
 		sregs.efer |= (EFER_LME | EFER_LMA | EFER_NX);
@@ -1153,3 +1153,25 @@ bool is_intel_cpu(void)
 	chunk = (const uint32_t *)("GenuineIntel");
 	return (ebx == chunk[0] && edx == chunk[1] && ecx == chunk[2]);
 }
+
+uint32_t kvm_get_cpuid_max(void)
+{
+	return kvm_get_supported_cpuid_entry(0x80000000)->eax;
+}
+
+void kvm_get_cpu_address_width(unsigned int *pa_bits, unsigned int *va_bits)
+{
+	struct kvm_cpuid_entry2 *entry;
+	bool pae;
+
+	/* SDM 4.1.4 */
+	if (kvm_get_cpuid_max() < 0x80000008) {
+		pae = kvm_get_supported_cpuid_entry(1)->edx & (1 << 6);
+		*pa_bits = pae ? 36 : 32;
+		*va_bits = 32;
+	} else {
+		entry = kvm_get_supported_cpuid_entry(0x80000008);
+		*pa_bits = entry->eax & 0xff;
+		*va_bits = (entry->eax >> 8) & 0xff;
+	}
+}
-- 
2.21.0

[PATCH v3 4/4] KVM: selftests: Remove duplicate guest mode handling

[Peter Xu]

Remove the duplication code in run_test() of dirty_log_test because
after some reordering of functions now we can directly use the outcome
of vm_create().

Meanwhile, with the new VM_MODE_PXXV48_4K, we can safely revert
b442324b58 too where we stick the x86_64 PA width to 39 bits for
dirty_log_test.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
---
 tools/testing/selftests/kvm/dirty_log_test.c  | 52 ++-----------------
 .../testing/selftests/kvm/include/kvm_util.h  |  4 ++
 tools/testing/selftests/kvm/lib/kvm_util.c    | 17 ++++++
 3 files changed, 26 insertions(+), 47 deletions(-)

diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index c86f83cb33e5..89fac11733a5 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -234,10 +234,8 @@ static struct kvm_vm *create_vm(enum vm_guest_mode mode, uint32_t vcpuid,
 static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 		     unsigned long interval, uint64_t phys_offset)
 {
-	unsigned int guest_pa_bits, guest_page_shift;
 	pthread_t vcpu_thread;
 	struct kvm_vm *vm;
-	uint64_t max_gfn;
 	unsigned long *bmap;
 
 	/*
@@ -252,60 +250,20 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 		       2ul << (DIRTY_MEM_BITS - PAGE_SHIFT_4K),
 		       guest_code);
 
-	switch (mode) {
-	case VM_MODE_P52V48_4K:
-	case VM_MODE_PXXV48_4K:
-		guest_pa_bits = 52;
-		guest_page_shift = 12;
-		break;
-	case VM_MODE_P52V48_64K:
-		guest_pa_bits = 52;
-		guest_page_shift = 16;
-		break;
-	case VM_MODE_P48V48_4K:
-		guest_pa_bits = 48;
-		guest_page_shift = 12;
-		break;
-	case VM_MODE_P48V48_64K:
-		guest_pa_bits = 48;
-		guest_page_shift = 16;
-		break;
-	case VM_MODE_P40V48_4K:
-		guest_pa_bits = 40;
-		guest_page_shift = 12;
-		break;
-	case VM_MODE_P40V48_64K:
-		guest_pa_bits = 40;
-		guest_page_shift = 16;
-		break;
-	default:
-		TEST_ASSERT(false, "Unknown guest mode, mode: 0x%x", mode);
-	}
-
-	DEBUG("Testing guest mode: %s\n", vm_guest_mode_string(mode));
-
-#ifdef __x86_64__
-	/*
-	 * FIXME
-	 * The x86_64 kvm selftests framework currently only supports a
-	 * single PML4 which restricts the number of physical address
-	 * bits we can change to 39.
-	 */
-	guest_pa_bits = 39;
-#endif
-	max_gfn = (1ul << (guest_pa_bits - guest_page_shift)) - 1;
-	guest_page_size = (1ul << guest_page_shift);
+	guest_page_size = vm_get_page_size(vm);
 	/*
 	 * A little more than 1G of guest page sized pages.  Cover the
 	 * case where the size is not aligned to 64 pages.
 	 */
-	guest_num_pages = (1ul << (DIRTY_MEM_BITS - guest_page_shift)) + 16;
+	guest_num_pages = (1ul << (DIRTY_MEM_BITS -
+				   vm_get_page_shift(vm))) + 16;
 	host_page_size = getpagesize();
 	host_num_pages = (guest_num_pages * guest_page_size) / host_page_size +
 			 !!((guest_num_pages * guest_page_size) % host_page_size);
 
 	if (!phys_offset) {
-		guest_test_phys_mem = (max_gfn - guest_num_pages) * guest_page_size;
+		guest_test_phys_mem = (vm_get_max_gfn(vm) -
+				       guest_num_pages) * guest_page_size;
 		guest_test_phys_mem &= ~(host_page_size - 1);
 	} else {
 		guest_test_phys_mem = phys_offset;
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index 8c71ec886aab..e7ee55853616 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -154,6 +154,10 @@ void vm_vcpu_add_default(struct kvm_vm *vm, uint32_t vcpuid, void *guest_code);
 
 bool vm_is_unrestricted_guest(struct kvm_vm *vm);
 
+unsigned int vm_get_page_size(struct kvm_vm *vm);
+unsigned int vm_get_page_shift(struct kvm_vm *vm);
+unsigned int vm_get_max_gfn(struct kvm_vm *vm);
+
 struct kvm_userspace_memory_region *
 kvm_userspace_memory_region_find(struct kvm_vm *vm, uint64_t start,
 				 uint64_t end);
diff --git a/tools/testing/selftests/kvm/lib/kvm_util.c b/tools/testing/selftests/kvm/lib/kvm_util.c
index bb8f993b25fb..80a338b5403c 100644
--- a/tools/testing/selftests/kvm/lib/kvm_util.c
+++ b/tools/testing/selftests/kvm/lib/kvm_util.c
@@ -136,6 +136,8 @@ struct kvm_vm *_vm_create(enum vm_guest_mode mode, uint64_t phy_pages, int perm)
 {
 	struct kvm_vm *vm;
 
+	DEBUG("Testing guest mode: %s\n", vm_guest_mode_string(mode));
+
 	vm = calloc(1, sizeof(*vm));
 	TEST_ASSERT(vm != NULL, "Insufficient Memory");
 
@@ -1650,3 +1652,18 @@ bool vm_is_unrestricted_guest(struct kvm_vm *vm)
 
 	return val == 'Y';
 }
+
+unsigned int vm_get_page_size(struct kvm_vm *vm)
+{
+	return vm->page_size;
+}
+
+unsigned int vm_get_page_shift(struct kvm_vm *vm)
+{
+	return vm->page_shift;
+}
+
+unsigned int vm_get_max_gfn(struct kvm_vm *vm)
+{
+	return vm->max_gfn;
+}
-- 
2.21.0

Re: [PATCH v3 0/4] KVM: selftests: Introduce VM_MODE_PXXV48_4K

[Paolo Bonzini]

On 30/08/19 03:36, Peter Xu wrote:
> v3:
> - pick r-b
> - refine DEBUG macro [Drew]
> 
> v2:
> - pick r-bs
> - rebased to master
> - fix pa width detect, check cpuid(1):edx.PAE(bit 6)
> - fix arm compilation issue [Drew]
> - fix indents issues and ways to define macros [Drew]
> - provide functions for fetching cpu pa/va bits [Drew]
> 
> This series originates from "[PATCH] KVM: selftests: Detect max PA
> width from cpuid" [1] and one of Drew's comments - instead of keeping
> the hackish line to overwrite guest_pa_bits all the time, this series
> introduced the new mode VM_MODE_PXXV48_4K for x86_64 platform.
> 
> The major issue is that even all the x86_64 kvm selftests are
> currently using the guest mode VM_MODE_P52V48_4K, many x86_64 hosts
> are not using 52 bits PA (and in most cases, far less).  If with luck
> we could be having 48 bits hosts, but it's more adhoc (I've observed 3
> x86_64 systems, they are having different PA width of 36, 39, 48).  I
> am not sure whether this is happening to the other archs as well, but
> it probably makes sense to bring the x86_64 tests to the real world on
> always using the correct PA bits.
> 
> A side effect of this series is that it will also fix the crash we've
> encountered on Xeon E3-1220 as mentioned [1] due to the
> differenciation of PA width.
> 
> With [1], we've observed AMD host issues when with NPT=off.  However a
> funny fact is that after I reworked into this series, the tests can
> instead pass on both NPT=on/off.  It could be that the series changes
> vm->pa_bits or other fields so something was affected.  I didn't dig
> more on that though, considering we should not lose anything.
> 
> [1] https://lkml.org/lkml/2019/8/26/141
> 
> Peter Xu (4):
>   KVM: selftests: Move vm type into _vm_create() internally
>   KVM: selftests: Create VM earlier for dirty log test
>   KVM: selftests: Introduce VM_MODE_PXXV48_4K
>   KVM: selftests: Remove duplicate guest mode handling
> 
>  tools/testing/selftests/kvm/dirty_log_test.c  | 79 +++++--------------
>  .../testing/selftests/kvm/include/kvm_util.h  | 18 ++++-
>  .../selftests/kvm/include/x86_64/processor.h  |  3 +
>  .../selftests/kvm/lib/aarch64/processor.c     |  3 +
>  tools/testing/selftests/kvm/lib/kvm_util.c    | 67 ++++++++++++----
>  .../selftests/kvm/lib/x86_64/processor.c      | 30 ++++++-
>  6 files changed, 121 insertions(+), 79 deletions(-)
> 

Queued, thanks.

Paolo