[GIT PULL 0/8] KVM: s390: extend selftests add more input checks

[GIT PULL 0/8] KVM: s390: extend selftests add more input checks

[Janosch Frank]

Paolo, Radim,

Thomas extended the selftests and added some input checks to KVM s390
ioctls. Cornelia contributed the documentation changes needed after
the added checks.

Please pull.

The following changes since commit 609488bc979f99f805f34e9a32c1e3b71179d10b:

  Linux 5.3-rc2 (2019-07-28 12:47:02 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git tags/kvm-s390-next-5.4-1

for you to fetch changes up to 81cb736c0c928444e2f4707513c167d5d39844a4:

  KVM: selftests: Test invalid bits in kvm_valid_regs and kvm_dirty_regs on s390x (2019-09-04 15:38:05 +0200)

----------------------------------------------------------------
* More selftests
* Improved KVM_S390_MEM_OP ioctl input checking
* Add kvm_valid_regs and kvm_dirty_regs invalid bit checking
----------------------------------------------------------------
Cornelia Huck (1):
      KVM: s390: improve documentation for S390_MEM_OP

Thomas Huth (7):
      KVM: selftests: Split ucall.c into architecture specific files
      KVM: selftests: Implement ucall() for s390x
      KVM: selftests: Enable dirty_log_test on s390x
      KVM: s390: Test for bad access register and size at the start of S390_MEM_OP
      KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl
      KVM: s390: Disallow invalid bits in kvm_valid_regs and kvm_dirty_regs
      KVM: selftests: Test invalid bits in kvm_valid_regs and kvm_dirty_regs on s390x

 Documentation/virt/kvm/api.txt                     |  14 +-
 arch/s390/include/uapi/asm/kvm.h                   |   6 +
 arch/s390/kvm/kvm-s390.c                           |   6 +-
 tools/testing/selftests/kvm/Makefile               |  10 +-
 tools/testing/selftests/kvm/dirty_log_test.c       |  61 +++++++-
 tools/testing/selftests/kvm/include/kvm_util.h     |   8 +-
 tools/testing/selftests/kvm/lib/aarch64/ucall.c    | 112 ++++++++++++++
 tools/testing/selftests/kvm/lib/s390x/ucall.c      |  56 +++++++
 tools/testing/selftests/kvm/lib/ucall.c            | 157 -------------------
 tools/testing/selftests/kvm/lib/x86_64/ucall.c     |  56 +++++++
 tools/testing/selftests/kvm/s390x/memop.c          | 166 +++++++++++++++++++++
 tools/testing/selftests/kvm/s390x/sync_regs_test.c |  36 ++++-
 12 files changed, 503 insertions(+), 185 deletions(-)
 create mode 100644 tools/testing/selftests/kvm/lib/aarch64/ucall.c
 create mode 100644 tools/testing/selftests/kvm/lib/s390x/ucall.c
 delete mode 100644 tools/testing/selftests/kvm/lib/ucall.c
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/ucall.c
 create mode 100644 tools/testing/selftests/kvm/s390x/memop.c

[GIT PULL 1/8] KVM: selftests: Split ucall.c into architecture specific files

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

The way we exit from a guest to userspace is very specific to the
architecture: On x86, we use PIO, on aarch64 we are using MMIO and on
s390x we're going to use an instruction instead. The possibility to
select a type via the ucall_type_t enum is currently also completely
unused, so the code in ucall.c currently looks more complex than
required. Let's split this up into architecture specific ucall.c
files instead, so we can get rid of the #ifdefs and the unnecessary
ucall_type_t handling.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Link: https://lore.kernel.org/r/20190731151525.17156-2-thuth@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 tools/testing/selftests/kvm/Makefile          |   6 +-
 tools/testing/selftests/kvm/dirty_log_test.c  |   2 +-
 .../testing/selftests/kvm/include/kvm_util.h  |   8 +-
 .../testing/selftests/kvm/lib/aarch64/ucall.c | 112 +++++++++++++
 tools/testing/selftests/kvm/lib/ucall.c       | 157 ------------------
 .../testing/selftests/kvm/lib/x86_64/ucall.c  |  56 +++++++
 6 files changed, 173 insertions(+), 168 deletions(-)
 create mode 100644 tools/testing/selftests/kvm/lib/aarch64/ucall.c
 delete mode 100644 tools/testing/selftests/kvm/lib/ucall.c
 create mode 100644 tools/testing/selftests/kvm/lib/x86_64/ucall.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index ba7849751989..a51e3b83df40 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -7,9 +7,9 @@ top_srcdir = ../../../..
 KSFT_KHDR_INSTALL := 1
 UNAME_M := $(shell uname -m)
 
-LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/ucall.c lib/sparsebit.c
-LIBKVM_x86_64 = lib/x86_64/processor.c lib/x86_64/vmx.c
-LIBKVM_aarch64 = lib/aarch64/processor.c
+LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/sparsebit.c
+LIBKVM_x86_64 = lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/ucall.c
+LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c
 LIBKVM_s390x = lib/s390x/processor.c
 
 TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test
diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index ceb52b952637..5d5ae1be4984 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -337,7 +337,7 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	vcpu_set_cpuid(vm, VCPU_ID, kvm_get_supported_cpuid());
 #endif
 #ifdef __aarch64__
-	ucall_init(vm, UCALL_MMIO, NULL);
+	ucall_init(vm, NULL);
 #endif
 
 	/* Export the shared variables to the guest */
diff --git a/tools/testing/selftests/kvm/include/kvm_util.h b/tools/testing/selftests/kvm/include/kvm_util.h
index e0e66b115ef2..5463b7896a0a 100644
--- a/tools/testing/selftests/kvm/include/kvm_util.h
+++ b/tools/testing/selftests/kvm/include/kvm_util.h
@@ -165,12 +165,6 @@ int vm_create_device(struct kvm_vm *vm, struct kvm_create_device *cd);
 	memcpy(&(g), _p, sizeof(g));				\
 })
 
-/* ucall implementation types */
-typedef enum {
-	UCALL_PIO,
-	UCALL_MMIO,
-} ucall_type_t;
-
 /* Common ucalls */
 enum {
 	UCALL_NONE,
@@ -186,7 +180,7 @@ struct ucall {
 	uint64_t args[UCALL_MAX_ARGS];
 };
 
-void ucall_init(struct kvm_vm *vm, ucall_type_t type, void *arg);
+void ucall_init(struct kvm_vm *vm, void *arg);
 void ucall_uninit(struct kvm_vm *vm);
 void ucall(uint64_t cmd, int nargs, ...);
 uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc);
diff --git a/tools/testing/selftests/kvm/lib/aarch64/ucall.c b/tools/testing/selftests/kvm/lib/aarch64/ucall.c
new file mode 100644
index 000000000000..6cd91970fbad
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/aarch64/ucall.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ucall support. A ucall is a "hypercall to userspace".
+ *
+ * Copyright (C) 2018, Red Hat, Inc.
+ */
+#include "kvm_util.h"
+#include "../kvm_util_internal.h"
+
+static vm_vaddr_t *ucall_exit_mmio_addr;
+
+static bool ucall_mmio_init(struct kvm_vm *vm, vm_paddr_t gpa)
+{
+	if (kvm_userspace_memory_region_find(vm, gpa, gpa + 1))
+		return false;
+
+	virt_pg_map(vm, gpa, gpa, 0);
+
+	ucall_exit_mmio_addr = (vm_vaddr_t *)gpa;
+	sync_global_to_guest(vm, ucall_exit_mmio_addr);
+
+	return true;
+}
+
+void ucall_init(struct kvm_vm *vm, void *arg)
+{
+	vm_paddr_t gpa, start, end, step, offset;
+	unsigned int bits;
+	bool ret;
+
+	if (arg) {
+		gpa = (vm_paddr_t)arg;
+		ret = ucall_mmio_init(vm, gpa);
+		TEST_ASSERT(ret, "Can't set ucall mmio address to %lx", gpa);
+		return;
+	}
+
+	/*
+	 * Find an address within the allowed physical and virtual address
+	 * spaces, that does _not_ have a KVM memory region associated with
+	 * it. Identity mapping an address like this allows the guest to
+	 * access it, but as KVM doesn't know what to do with it, it
+	 * will assume it's something userspace handles and exit with
+	 * KVM_EXIT_MMIO. Well, at least that's how it works for AArch64.
+	 * Here we start with a guess that the addresses around 5/8th
+	 * of the allowed space are unmapped and then work both down and
+	 * up from there in 1/16th allowed space sized steps.
+	 *
+	 * Note, we need to use VA-bits - 1 when calculating the allowed
+	 * virtual address space for an identity mapping because the upper
+	 * half of the virtual address space is the two's complement of the
+	 * lower and won't match physical addresses.
+	 */
+	bits = vm->va_bits - 1;
+	bits = vm->pa_bits < bits ? vm->pa_bits : bits;
+	end = 1ul << bits;
+	start = end * 5 / 8;
+	step = end / 16;
+	for (offset = 0; offset < end - start; offset += step) {
+		if (ucall_mmio_init(vm, start - offset))
+			return;
+		if (ucall_mmio_init(vm, start + offset))
+			return;
+	}
+	TEST_ASSERT(false, "Can't find a ucall mmio address");
+}
+
+void ucall_uninit(struct kvm_vm *vm)
+{
+	ucall_exit_mmio_addr = 0;
+	sync_global_to_guest(vm, ucall_exit_mmio_addr);
+}
+
+void ucall(uint64_t cmd, int nargs, ...)
+{
+	struct ucall uc = {
+		.cmd = cmd,
+	};
+	va_list va;
+	int i;
+
+	nargs = nargs <= UCALL_MAX_ARGS ? nargs : UCALL_MAX_ARGS;
+
+	va_start(va, nargs);
+	for (i = 0; i < nargs; ++i)
+		uc.args[i] = va_arg(va, uint64_t);
+	va_end(va);
+
+	*ucall_exit_mmio_addr = (vm_vaddr_t)&uc;
+}
+
+uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc)
+{
+	struct kvm_run *run = vcpu_state(vm, vcpu_id);
+	struct ucall ucall = {};
+
+	if (run->exit_reason == KVM_EXIT_MMIO &&
+	    run->mmio.phys_addr == (uint64_t)ucall_exit_mmio_addr) {
+		vm_vaddr_t gva;
+
+		TEST_ASSERT(run->mmio.is_write && run->mmio.len == 8,
+			    "Unexpected ucall exit mmio address access");
+		memcpy(&gva, run->mmio.data, sizeof(gva));
+		memcpy(&ucall, addr_gva2hva(vm, gva), sizeof(ucall));
+
+		vcpu_run_complete_io(vm, vcpu_id);
+		if (uc)
+			memcpy(uc, &ucall, sizeof(ucall));
+	}
+
+	return ucall.cmd;
+}
diff --git a/tools/testing/selftests/kvm/lib/ucall.c b/tools/testing/selftests/kvm/lib/ucall.c
deleted file mode 100644
index dd9a66700f96..000000000000
--- a/tools/testing/selftests/kvm/lib/ucall.c
+++ /dev/null
@@ -1,157 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * ucall support. A ucall is a "hypercall to userspace".
- *
- * Copyright (C) 2018, Red Hat, Inc.
- */
-#include "kvm_util.h"
-#include "kvm_util_internal.h"
-
-#define UCALL_PIO_PORT ((uint16_t)0x1000)
-
-static ucall_type_t ucall_type;
-static vm_vaddr_t *ucall_exit_mmio_addr;
-
-static bool ucall_mmio_init(struct kvm_vm *vm, vm_paddr_t gpa)
-{
-	if (kvm_userspace_memory_region_find(vm, gpa, gpa + 1))
-		return false;
-
-	virt_pg_map(vm, gpa, gpa, 0);
-
-	ucall_exit_mmio_addr = (vm_vaddr_t *)gpa;
-	sync_global_to_guest(vm, ucall_exit_mmio_addr);
-
-	return true;
-}
-
-void ucall_init(struct kvm_vm *vm, ucall_type_t type, void *arg)
-{
-	ucall_type = type;
-	sync_global_to_guest(vm, ucall_type);
-
-	if (type == UCALL_PIO)
-		return;
-
-	if (type == UCALL_MMIO) {
-		vm_paddr_t gpa, start, end, step, offset;
-		unsigned bits;
-		bool ret;
-
-		if (arg) {
-			gpa = (vm_paddr_t)arg;
-			ret = ucall_mmio_init(vm, gpa);
-			TEST_ASSERT(ret, "Can't set ucall mmio address to %lx", gpa);
-			return;
-		}
-
-		/*
-		 * Find an address within the allowed physical and virtual address
-		 * spaces, that does _not_ have a KVM memory region associated with
-		 * it. Identity mapping an address like this allows the guest to
-		 * access it, but as KVM doesn't know what to do with it, it
-		 * will assume it's something userspace handles and exit with
-		 * KVM_EXIT_MMIO. Well, at least that's how it works for AArch64.
-		 * Here we start with a guess that the addresses around 5/8th
-		 * of the allowed space are unmapped and then work both down and
-		 * up from there in 1/16th allowed space sized steps.
-		 *
-		 * Note, we need to use VA-bits - 1 when calculating the allowed
-		 * virtual address space for an identity mapping because the upper
-		 * half of the virtual address space is the two's complement of the
-		 * lower and won't match physical addresses.
-		 */
-		bits = vm->va_bits - 1;
-		bits = vm->pa_bits < bits ? vm->pa_bits : bits;
-		end = 1ul << bits;
-		start = end * 5 / 8;
-		step = end / 16;
-		for (offset = 0; offset < end - start; offset += step) {
-			if (ucall_mmio_init(vm, start - offset))
-				return;
-			if (ucall_mmio_init(vm, start + offset))
-				return;
-		}
-		TEST_ASSERT(false, "Can't find a ucall mmio address");
-	}
-}
-
-void ucall_uninit(struct kvm_vm *vm)
-{
-	ucall_type = 0;
-	sync_global_to_guest(vm, ucall_type);
-	ucall_exit_mmio_addr = 0;
-	sync_global_to_guest(vm, ucall_exit_mmio_addr);
-}
-
-static void ucall_pio_exit(struct ucall *uc)
-{
-#ifdef __x86_64__
-	asm volatile("in %[port], %%al"
-		: : [port] "d" (UCALL_PIO_PORT), "D" (uc) : "rax");
-#endif
-}
-
-static void ucall_mmio_exit(struct ucall *uc)
-{
-	*ucall_exit_mmio_addr = (vm_vaddr_t)uc;
-}
-
-void ucall(uint64_t cmd, int nargs, ...)
-{
-	struct ucall uc = {
-		.cmd = cmd,
-	};
-	va_list va;
-	int i;
-
-	nargs = nargs <= UCALL_MAX_ARGS ? nargs : UCALL_MAX_ARGS;
-
-	va_start(va, nargs);
-	for (i = 0; i < nargs; ++i)
-		uc.args[i] = va_arg(va, uint64_t);
-	va_end(va);
-
-	switch (ucall_type) {
-	case UCALL_PIO:
-		ucall_pio_exit(&uc);
-		break;
-	case UCALL_MMIO:
-		ucall_mmio_exit(&uc);
-		break;
-	};
-}
-
-uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc)
-{
-	struct kvm_run *run = vcpu_state(vm, vcpu_id);
-	struct ucall ucall = {};
-	bool got_ucall = false;
-
-#ifdef __x86_64__
-	if (ucall_type == UCALL_PIO && run->exit_reason == KVM_EXIT_IO &&
-	    run->io.port == UCALL_PIO_PORT) {
-		struct kvm_regs regs;
-		vcpu_regs_get(vm, vcpu_id, &regs);
-		memcpy(&ucall, addr_gva2hva(vm, (vm_vaddr_t)regs.rdi), sizeof(ucall));
-		got_ucall = true;
-	}
-#endif
-	if (ucall_type == UCALL_MMIO && run->exit_reason == KVM_EXIT_MMIO &&
-	    run->mmio.phys_addr == (uint64_t)ucall_exit_mmio_addr) {
-		vm_vaddr_t gva;
-		TEST_ASSERT(run->mmio.is_write && run->mmio.len == 8,
-			    "Unexpected ucall exit mmio address access");
-		memcpy(&gva, run->mmio.data, sizeof(gva));
-		memcpy(&ucall, addr_gva2hva(vm, gva), sizeof(ucall));
-		got_ucall = true;
-	}
-
-	if (got_ucall) {
-		vcpu_run_complete_io(vm, vcpu_id);
-		if (uc)
-			memcpy(uc, &ucall, sizeof(ucall));
-	}
-
-	return ucall.cmd;
-}
diff --git a/tools/testing/selftests/kvm/lib/x86_64/ucall.c b/tools/testing/selftests/kvm/lib/x86_64/ucall.c
new file mode 100644
index 000000000000..4bfc9a90b1de
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/x86_64/ucall.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ucall support. A ucall is a "hypercall to userspace".
+ *
+ * Copyright (C) 2018, Red Hat, Inc.
+ */
+#include "kvm_util.h"
+
+#define UCALL_PIO_PORT ((uint16_t)0x1000)
+
+void ucall_init(struct kvm_vm *vm, void *arg)
+{
+}
+
+void ucall_uninit(struct kvm_vm *vm)
+{
+}
+
+void ucall(uint64_t cmd, int nargs, ...)
+{
+	struct ucall uc = {
+		.cmd = cmd,
+	};
+	va_list va;
+	int i;
+
+	nargs = nargs <= UCALL_MAX_ARGS ? nargs : UCALL_MAX_ARGS;
+
+	va_start(va, nargs);
+	for (i = 0; i < nargs; ++i)
+		uc.args[i] = va_arg(va, uint64_t);
+	va_end(va);
+
+	asm volatile("in %[port], %%al"
+		: : [port] "d" (UCALL_PIO_PORT), "D" (&uc) : "rax");
+}
+
+uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc)
+{
+	struct kvm_run *run = vcpu_state(vm, vcpu_id);
+	struct ucall ucall = {};
+
+	if (run->exit_reason == KVM_EXIT_IO && run->io.port == UCALL_PIO_PORT) {
+		struct kvm_regs regs;
+
+		vcpu_regs_get(vm, vcpu_id, &regs);
+		memcpy(&ucall, addr_gva2hva(vm, (vm_vaddr_t)regs.rdi),
+		       sizeof(ucall));
+
+		vcpu_run_complete_io(vm, vcpu_id);
+		if (uc)
+			memcpy(uc, &ucall, sizeof(ucall));
+	}
+
+	return ucall.cmd;
+}
-- 
2.20.1

[GIT PULL 2/8] KVM: selftests: Implement ucall() for s390x

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

On s390x, we can neither exit via PIO nor MMIO, but have to use an
instruction like DIAGNOSE. Now that ucall() is implemented, we can
use it in the sync_reg_test on s390x, too.

Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20190731151525.17156-3-thuth@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 tools/testing/selftests/kvm/Makefile          |  2 +-
 tools/testing/selftests/kvm/lib/s390x/ucall.c | 56 +++++++++++++++++++
 .../selftests/kvm/s390x/sync_regs_test.c      |  6 +-
 3 files changed, 61 insertions(+), 3 deletions(-)
 create mode 100644 tools/testing/selftests/kvm/lib/s390x/ucall.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index a51e3b83df40..75ea1ecbf85a 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -10,7 +10,7 @@ UNAME_M := $(shell uname -m)
 LIBKVM = lib/assert.c lib/elf.c lib/io.c lib/kvm_util.c lib/sparsebit.c
 LIBKVM_x86_64 = lib/x86_64/processor.c lib/x86_64/vmx.c lib/x86_64/ucall.c
 LIBKVM_aarch64 = lib/aarch64/processor.c lib/aarch64/ucall.c
-LIBKVM_s390x = lib/s390x/processor.c
+LIBKVM_s390x = lib/s390x/processor.c lib/s390x/ucall.c
 
 TEST_GEN_PROGS_x86_64 = x86_64/cr4_cpuid_sync_test
 TEST_GEN_PROGS_x86_64 += x86_64/evmcs_test
diff --git a/tools/testing/selftests/kvm/lib/s390x/ucall.c b/tools/testing/selftests/kvm/lib/s390x/ucall.c
new file mode 100644
index 000000000000..fd589dc9bfab
--- /dev/null
+++ b/tools/testing/selftests/kvm/lib/s390x/ucall.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * ucall support. A ucall is a "hypercall to userspace".
+ *
+ * Copyright (C) 2019 Red Hat, Inc.
+ */
+#include "kvm_util.h"
+
+void ucall_init(struct kvm_vm *vm, void *arg)
+{
+}
+
+void ucall_uninit(struct kvm_vm *vm)
+{
+}
+
+void ucall(uint64_t cmd, int nargs, ...)
+{
+	struct ucall uc = {
+		.cmd = cmd,
+	};
+	va_list va;
+	int i;
+
+	nargs = nargs <= UCALL_MAX_ARGS ? nargs : UCALL_MAX_ARGS;
+
+	va_start(va, nargs);
+	for (i = 0; i < nargs; ++i)
+		uc.args[i] = va_arg(va, uint64_t);
+	va_end(va);
+
+	/* Exit via DIAGNOSE 0x501 (normally used for breakpoints) */
+	asm volatile ("diag 0,%0,0x501" : : "a"(&uc) : "memory");
+}
+
+uint64_t get_ucall(struct kvm_vm *vm, uint32_t vcpu_id, struct ucall *uc)
+{
+	struct kvm_run *run = vcpu_state(vm, vcpu_id);
+	struct ucall ucall = {};
+
+	if (run->exit_reason == KVM_EXIT_S390_SIEIC &&
+	    run->s390_sieic.icptcode == 4 &&
+	    (run->s390_sieic.ipa >> 8) == 0x83 &&    /* 0x83 means DIAGNOSE */
+	    (run->s390_sieic.ipb >> 16) == 0x501) {
+		int reg = run->s390_sieic.ipa & 0xf;
+
+		memcpy(&ucall, addr_gva2hva(vm, run->s.regs.gprs[reg]),
+		       sizeof(ucall));
+
+		vcpu_run_complete_io(vm, vcpu_id);
+		if (uc)
+			memcpy(uc, &ucall, sizeof(ucall));
+	}
+
+	return ucall.cmd;
+}
diff --git a/tools/testing/selftests/kvm/s390x/sync_regs_test.c b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
index e85ff0d69548..bbc93094519b 100644
--- a/tools/testing/selftests/kvm/s390x/sync_regs_test.c
+++ b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
@@ -25,9 +25,11 @@
 
 static void guest_code(void)
 {
+	register u64 stage asm("11") = 0;
+
 	for (;;) {
-		asm volatile ("diag 0,0,0x501");
-		asm volatile ("ahi 11,1");
+		GUEST_SYNC(0);
+		asm volatile ("ahi %0,1" : : "r"(stage));
 	}
 }
 
-- 
2.20.1

[GIT PULL 3/8] KVM: selftests: Enable dirty_log_test on s390x

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

To run the dirty_log_test on s390x, we have to make sure that we
access the dirty log bitmap with little endian byte ordering and
we have to properly align the memslot of the guest.
Also all dirty bits of a segment are set once on s390x when one
of the pages of a segment are written to for the first time, so
we have to make sure that we touch all pages during the first
iteration to keep the test in sync here.
DEFAULT_GUEST_TEST_MEM needs an adjustment, too. On some s390x
distributions, the ELF binary is linked to address 0x80000000,
so we have to avoid that our test region overlaps into this area.
0xc0000000 seems to be a good alternative that should work on x86
and aarch64, too.

Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/r/20190731151525.17156-4-thuth@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 tools/testing/selftests/kvm/Makefile         |  1 +
 tools/testing/selftests/kvm/dirty_log_test.c | 59 +++++++++++++++++---
 2 files changed, 53 insertions(+), 7 deletions(-)

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 75ea1ecbf85a..1b48a94b4350 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -33,6 +33,7 @@ TEST_GEN_PROGS_aarch64 += dirty_log_test
 TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus
 
 TEST_GEN_PROGS_s390x += s390x/sync_regs_test
+TEST_GEN_PROGS_s390x += dirty_log_test
 TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
 
 TEST_GEN_PROGS += $(TEST_GEN_PROGS_$(UNAME_M))
diff --git a/tools/testing/selftests/kvm/dirty_log_test.c b/tools/testing/selftests/kvm/dirty_log_test.c
index 5d5ae1be4984..dc3346e090f5 100644
--- a/tools/testing/selftests/kvm/dirty_log_test.c
+++ b/tools/testing/selftests/kvm/dirty_log_test.c
@@ -26,8 +26,8 @@
 /* The memory slot index to track dirty pages */
 #define TEST_MEM_SLOT_INDEX		1
 
-/* Default guest test memory offset, 1G */
-#define DEFAULT_GUEST_TEST_MEM		0x40000000
+/* Default guest test virtual memory offset */
+#define DEFAULT_GUEST_TEST_MEM		0xc0000000
 
 /* How many pages to dirty for each guest loop */
 #define TEST_PAGES_PER_LOOP		1024
@@ -38,6 +38,27 @@
 /* Interval for each host loop (ms) */
 #define TEST_HOST_LOOP_INTERVAL		10UL
 
+/* Dirty bitmaps are always little endian, so we need to swap on big endian */
+#if defined(__s390x__)
+# define BITOP_LE_SWIZZLE	((BITS_PER_LONG-1) & ~0x7)
+# define test_bit_le(nr, addr) \
+	test_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
+# define set_bit_le(nr, addr) \
+	set_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
+# define clear_bit_le(nr, addr) \
+	clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
+# define test_and_set_bit_le(nr, addr) \
+	test_and_set_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
+# define test_and_clear_bit_le(nr, addr) \
+	test_and_clear_bit((nr) ^ BITOP_LE_SWIZZLE, addr)
+#else
+# define test_bit_le		test_bit
+# define set_bit_le		set_bit
+# define clear_bit_le		clear_bit
+# define test_and_set_bit_le	test_and_set_bit
+# define test_and_clear_bit_le	test_and_clear_bit
+#endif
+
 /*
  * Guest/Host shared variables. Ensure addr_gva2hva() and/or
  * sync_global_to/from_guest() are used when accessing from
@@ -69,11 +90,23 @@ static uint64_t guest_test_virt_mem = DEFAULT_GUEST_TEST_MEM;
  */
 static void guest_code(void)
 {
+	uint64_t addr;
 	int i;
 
+	/*
+	 * On s390x, all pages of a 1M segment are initially marked as dirty
+	 * when a page of the segment is written to for the very first time.
+	 * To compensate this specialty in this test, we need to touch all
+	 * pages during the first iteration.
+	 */
+	for (i = 0; i < guest_num_pages; i++) {
+		addr = guest_test_virt_mem + i * guest_page_size;
+		*(uint64_t *)addr = READ_ONCE(iteration);
+	}
+
 	while (true) {
 		for (i = 0; i < TEST_PAGES_PER_LOOP; i++) {
-			uint64_t addr = guest_test_virt_mem;
+			addr = guest_test_virt_mem;
 			addr += (READ_ONCE(random_array[i]) % guest_num_pages)
 				* guest_page_size;
 			addr &= ~(host_page_size - 1);
@@ -158,15 +191,15 @@ static void vm_dirty_log_verify(unsigned long *bmap)
 		value_ptr = host_test_mem + page * host_page_size;
 
 		/* If this is a special page that we were tracking... */
-		if (test_and_clear_bit(page, host_bmap_track)) {
+		if (test_and_clear_bit_le(page, host_bmap_track)) {
 			host_track_next_count++;
-			TEST_ASSERT(test_bit(page, bmap),
+			TEST_ASSERT(test_bit_le(page, bmap),
 				    "Page %"PRIu64" should have its dirty bit "
 				    "set in this iteration but it is missing",
 				    page);
 		}
 
-		if (test_bit(page, bmap)) {
+		if (test_bit_le(page, bmap)) {
 			host_dirty_count++;
 			/*
 			 * If the bit is set, the value written onto
@@ -209,7 +242,7 @@ static void vm_dirty_log_verify(unsigned long *bmap)
 				 * should report its dirtyness in the
 				 * next run
 				 */
-				set_bit(page, host_bmap_track);
+				set_bit_le(page, host_bmap_track);
 			}
 		}
 	}
@@ -293,6 +326,10 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 	 * case where the size is not aligned to 64 pages.
 	 */
 	guest_num_pages = (1ul << (30 - guest_page_shift)) + 16;
+#ifdef __s390x__
+	/* Round up to multiple of 1M (segment size) */
+	guest_num_pages = (guest_num_pages + 0xff) & ~0xffUL;
+#endif
 	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);
@@ -304,6 +341,11 @@ static void run_test(enum vm_guest_mode mode, unsigned long iterations,
 		guest_test_phys_mem = phys_offset;
 	}
 
+#ifdef __s390x__
+	/* Align to 1M (segment size) */
+	guest_test_phys_mem &= ~((1 << 20) - 1);
+#endif
+
 	DEBUG("guest physical test memory offset: 0x%lx\n", guest_test_phys_mem);
 
 	bmap = bitmap_alloc(host_num_pages);
@@ -454,6 +496,9 @@ int main(int argc, char *argv[])
 		vm_guest_mode_params_init(VM_MODE_P48V48_64K, true, true);
 	}
 #endif
+#ifdef __s390x__
+	vm_guest_mode_params_init(VM_MODE_P40V48_4K, true, true);
+#endif
 
 	while ((opt = getopt(argc, argv, "hi:I:p:m:")) != -1) {
 		switch (opt) {
-- 
2.20.1

[GIT PULL 4/8] KVM: s390: Test for bad access register and size at the start of S390_MEM_OP

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

If the KVM_S390_MEM_OP ioctl is called with an access register >= 16,
then there is certainly a bug in the calling userspace application.
We check for wrong access registers, but only if the vCPU was already
in the access register mode before (i.e. the SIE block has recorded
it). The check is also buried somewhere deep in the calling chain (in
the function ar_translation()), so this is somewhat hard to find.

It's better to always report an error to the userspace in case this
field is set wrong, and it's safer in the KVM code if we block wrong
values here early instead of relying on a check somewhere deep down
the calling chain, so let's add another check to kvm_s390_guest_mem_op()
directly.

We also should check that the "size" is non-zero here (thanks to Janosch
Frank for the hint!). If we do not check the size, we could call vmalloc()
with this 0 value, and this will cause a kernel warning.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lkml.kernel.org/r/20190829122517.31042-1-thuth@redhat.com
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 arch/s390/kvm/kvm-s390.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 3f520cd837fb..d41c091546b7 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4265,7 +4265,7 @@ static long kvm_s390_guest_mem_op(struct kvm_vcpu *vcpu,
 	const u64 supported_flags = KVM_S390_MEMOP_F_INJECT_EXCEPTION
 				    | KVM_S390_MEMOP_F_CHECK_ONLY;
 
-	if (mop->flags & ~supported_flags)
+	if (mop->flags & ~supported_flags || mop->ar >= NUM_ACRS || !mop->size)
 		return -EINVAL;
 
 	if (mop->size > MEM_OP_MAX_SIZE)
-- 
2.20.1

[GIT PULL 5/8] KVM: s390: improve documentation for S390_MEM_OP

[Janosch Frank]

From: Cornelia Huck <cohuck@redhat.com>

Explicitly specify the valid ranges for size and ar, and reword
buf requirements a bit.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: https://lkml.kernel.org/r/20190829124746.28665-1-cohuck@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 Documentation/virt/kvm/api.txt | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/Documentation/virt/kvm/api.txt b/Documentation/virt/kvm/api.txt
index 2d067767b617..76c9d6fdbfdb 100644
--- a/Documentation/virt/kvm/api.txt
+++ b/Documentation/virt/kvm/api.txt
@@ -3079,12 +3079,14 @@ This exception is also raised directly at the corresponding VCPU if the
 flag KVM_S390_MEMOP_F_INJECT_EXCEPTION is set in the "flags" field.
 
 The start address of the memory region has to be specified in the "gaddr"
-field, and the length of the region in the "size" field. "buf" is the buffer
-supplied by the userspace application where the read data should be written
-to for KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written
-is stored for a KVM_S390_MEMOP_LOGICAL_WRITE. "buf" is unused and can be NULL
-when KVM_S390_MEMOP_F_CHECK_ONLY is specified. "ar" designates the access
-register number to be used.
+field, and the length of the region in the "size" field (which must not
+be 0). The maximum value for "size" can be obtained by checking the
+KVM_CAP_S390_MEM_OP capability. "buf" is the buffer supplied by the
+userspace application where the read data should be written to for
+KVM_S390_MEMOP_LOGICAL_READ, or where the data that should be written is
+stored for a KVM_S390_MEMOP_LOGICAL_WRITE. When KVM_S390_MEMOP_F_CHECK_ONLY
+is specified, "buf" is unused and can be NULL. "ar" designates the access
+register number to be used; the valid range is 0..15.
 
 The "reserved" field is meant for future extensions. It is not used by
 KVM with the currently defined set of flags.
-- 
2.20.1

[GIT PULL 6/8] KVM: selftests: Add a test for the KVM_S390_MEM_OP ioctl

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

Check that we can write and read the guest memory with this s390x
ioctl, and that some error cases are handled correctly.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lkml.kernel.org/r/20190829130732.580-1-thuth@redhat.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
---
 tools/testing/selftests/kvm/Makefile      |   1 +
 tools/testing/selftests/kvm/s390x/memop.c | 166 ++++++++++++++++++++++
 2 files changed, 167 insertions(+)
 create mode 100644 tools/testing/selftests/kvm/s390x/memop.c

diff --git a/tools/testing/selftests/kvm/Makefile b/tools/testing/selftests/kvm/Makefile
index 1b48a94b4350..62c591f87dab 100644
--- a/tools/testing/selftests/kvm/Makefile
+++ b/tools/testing/selftests/kvm/Makefile
@@ -32,6 +32,7 @@ TEST_GEN_PROGS_aarch64 += clear_dirty_log_test
 TEST_GEN_PROGS_aarch64 += dirty_log_test
 TEST_GEN_PROGS_aarch64 += kvm_create_max_vcpus
 
+TEST_GEN_PROGS_s390x = s390x/memop
 TEST_GEN_PROGS_s390x += s390x/sync_regs_test
 TEST_GEN_PROGS_s390x += dirty_log_test
 TEST_GEN_PROGS_s390x += kvm_create_max_vcpus
diff --git a/tools/testing/selftests/kvm/s390x/memop.c b/tools/testing/selftests/kvm/s390x/memop.c
new file mode 100644
index 000000000000..9edaa9a134ce
--- /dev/null
+++ b/tools/testing/selftests/kvm/s390x/memop.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Test for s390x KVM_S390_MEM_OP
+ *
+ * Copyright (C) 2019, Red Hat, Inc.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+#include "test_util.h"
+#include "kvm_util.h"
+
+#define VCPU_ID 1
+
+static uint8_t mem1[65536];
+static uint8_t mem2[65536];
+
+static void guest_code(void)
+{
+	int i;
+
+	for (;;) {
+		for (i = 0; i < sizeof(mem2); i++)
+			mem2[i] = mem1[i];
+		GUEST_SYNC(0);
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	struct kvm_vm *vm;
+	struct kvm_run *run;
+	struct kvm_s390_mem_op ksmo;
+	int rv, i, maxsize;
+
+	setbuf(stdout, NULL);	/* Tell stdout not to buffer its content */
+
+	maxsize = kvm_check_cap(KVM_CAP_S390_MEM_OP);
+	if (!maxsize) {
+		fprintf(stderr, "CAP_S390_MEM_OP not supported -> skip test\n");
+		exit(KSFT_SKIP);
+	}
+	if (maxsize > sizeof(mem1))
+		maxsize = sizeof(mem1);
+
+	/* Create VM */
+	vm = vm_create_default(VCPU_ID, 0, guest_code);
+	run = vcpu_state(vm, VCPU_ID);
+
+	for (i = 0; i < sizeof(mem1); i++)
+		mem1[i] = i * i + i;
+
+	/* Set the first array */
+	ksmo.gaddr = addr_gva2gpa(vm, (uintptr_t)mem1);
+	ksmo.flags = 0;
+	ksmo.size = maxsize;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 0;
+	vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+
+	/* Let the guest code copy the first array to the second */
+	vcpu_run(vm, VCPU_ID);
+	TEST_ASSERT(run->exit_reason == KVM_EXIT_S390_SIEIC,
+		    "Unexpected exit reason: %u (%s)\n",
+		    run->exit_reason,
+		    exit_reason_str(run->exit_reason));
+
+	memset(mem2, 0xaa, sizeof(mem2));
+
+	/* Get the second array */
+	ksmo.gaddr = (uintptr_t)mem2;
+	ksmo.flags = 0;
+	ksmo.size = maxsize;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_READ;
+	ksmo.buf = (uintptr_t)mem2;
+	ksmo.ar = 0;
+	vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+
+	TEST_ASSERT(!memcmp(mem1, mem2, maxsize),
+		    "Memory contents do not match!");
+
+	/* Check error conditions - first bad size: */
+	ksmo.gaddr = (uintptr_t)mem1;
+	ksmo.flags = 0;
+	ksmo.size = -1;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == E2BIG, "ioctl allows insane sizes");
+
+	/* Zero size: */
+	ksmo.gaddr = (uintptr_t)mem1;
+	ksmo.flags = 0;
+	ksmo.size = 0;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && (errno == EINVAL || errno == ENOMEM),
+		    "ioctl allows 0 as size");
+
+	/* Bad flags: */
+	ksmo.gaddr = (uintptr_t)mem1;
+	ksmo.flags = -1;
+	ksmo.size = maxsize;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows all flags");
+
+	/* Bad operation: */
+	ksmo.gaddr = (uintptr_t)mem1;
+	ksmo.flags = 0;
+	ksmo.size = maxsize;
+	ksmo.op = -1;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows bad operations");
+
+	/* Bad guest address: */
+	ksmo.gaddr = ~0xfffUL;
+	ksmo.flags = KVM_S390_MEMOP_F_CHECK_ONLY;
+	ksmo.size = maxsize;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv > 0, "ioctl does not report bad guest memory access");
+
+	/* Bad host address: */
+	ksmo.gaddr = (uintptr_t)mem1;
+	ksmo.flags = 0;
+	ksmo.size = maxsize;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = 0;
+	ksmo.ar = 0;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == EFAULT,
+		    "ioctl does not report bad host memory address");
+
+	/* Bad access register: */
+	run->psw_mask &= ~(3UL << (63 - 17));
+	run->psw_mask |= 1UL << (63 - 17);  /* Enable AR mode */
+	vcpu_run(vm, VCPU_ID);              /* To sync new state to SIE block */
+	ksmo.gaddr = (uintptr_t)mem1;
+	ksmo.flags = 0;
+	ksmo.size = maxsize;
+	ksmo.op = KVM_S390_MEMOP_LOGICAL_WRITE;
+	ksmo.buf = (uintptr_t)mem1;
+	ksmo.ar = 17;
+	rv = _vcpu_ioctl(vm, VCPU_ID, KVM_S390_MEM_OP, &ksmo);
+	TEST_ASSERT(rv == -1 && errno == EINVAL, "ioctl allows ARs > 15");
+	run->psw_mask &= ~(3UL << (63 - 17));   /* Disable AR mode */
+	vcpu_run(vm, VCPU_ID);                  /* Run to sync new state */
+
+	kvm_vm_free(vm);
+
+	return 0;
+}
-- 
2.20.1

[GIT PULL 7/8] KVM: s390: Disallow invalid bits in kvm_valid_regs and kvm_dirty_regs

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

If unknown bits are set in kvm_valid_regs or kvm_dirty_regs, this
clearly indicates that something went wrong in the KVM userspace
application. The x86 variant of KVM already contains a check for
bad bits, so let's do the same on s390x now, too.

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/lkml/20190904085200.29021-2-thuth@redhat.com/
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 arch/s390/include/uapi/asm/kvm.h | 6 ++++++
 arch/s390/kvm/kvm-s390.c         | 4 ++++
 2 files changed, 10 insertions(+)

diff --git a/arch/s390/include/uapi/asm/kvm.h b/arch/s390/include/uapi/asm/kvm.h
index 47104e5b47fd..436ec7636927 100644
--- a/arch/s390/include/uapi/asm/kvm.h
+++ b/arch/s390/include/uapi/asm/kvm.h
@@ -231,6 +231,12 @@ struct kvm_guest_debug_arch {
 #define KVM_SYNC_GSCB   (1UL << 9)
 #define KVM_SYNC_BPBC   (1UL << 10)
 #define KVM_SYNC_ETOKEN (1UL << 11)
+
+#define KVM_SYNC_S390_VALID_FIELDS \
+	(KVM_SYNC_PREFIX | KVM_SYNC_GPRS | KVM_SYNC_ACRS | KVM_SYNC_CRS | \
+	 KVM_SYNC_ARCH0 | KVM_SYNC_PFAULT | KVM_SYNC_VRS | KVM_SYNC_RICCB | \
+	 KVM_SYNC_FPRS | KVM_SYNC_GSCB | KVM_SYNC_BPBC | KVM_SYNC_ETOKEN)
+
 /* length and alignment of the sdnx as a power of two */
 #define SDNXC 8
 #define SDNXL (1UL << SDNXC)
diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index d41c091546b7..a3d4527ac23b 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -4008,6 +4008,10 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
 	if (kvm_run->immediate_exit)
 		return -EINTR;
 
+	if (kvm_run->kvm_valid_regs & ~KVM_SYNC_S390_VALID_FIELDS ||
+	    kvm_run->kvm_dirty_regs & ~KVM_SYNC_S390_VALID_FIELDS)
+		return -EINVAL;
+
 	vcpu_load(vcpu);
 
 	if (guestdbg_exit_pending(vcpu)) {
-- 
2.20.1

[GIT PULL 8/8] KVM: selftests: Test invalid bits in kvm_valid_regs and kvm_dirty_regs on s390x

[Janosch Frank]

From: Thomas Huth <thuth@redhat.com>

Now that we disallow invalid bits in kvm_valid_regs and kvm_dirty_regs
on s390x, too, we should also check this condition in the selftests.
The code has been taken from the x86-version of the sync_regs_test.

Reviewed-by: Janosch Frank <frankja@linux.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>
Link: https://lore.kernel.org/lkml/20190904085200.29021-3-thuth@redhat.com/
Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 .../selftests/kvm/s390x/sync_regs_test.c      | 30 +++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/tools/testing/selftests/kvm/s390x/sync_regs_test.c b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
index bbc93094519b..d5290b4ad636 100644
--- a/tools/testing/selftests/kvm/s390x/sync_regs_test.c
+++ b/tools/testing/selftests/kvm/s390x/sync_regs_test.c
@@ -85,6 +85,36 @@ int main(int argc, char *argv[])
 
 	run = vcpu_state(vm, VCPU_ID);
 
+	/* Request reading invalid register set from VCPU. */
+	run->kvm_valid_regs = INVALID_SYNC_FIELD;
+	rv = _vcpu_run(vm, VCPU_ID);
+	TEST_ASSERT(rv < 0 && errno == EINVAL,
+		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
+		    rv);
+	vcpu_state(vm, VCPU_ID)->kvm_valid_regs = 0;
+
+	run->kvm_valid_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
+	rv = _vcpu_run(vm, VCPU_ID);
+	TEST_ASSERT(rv < 0 && errno == EINVAL,
+		    "Invalid kvm_valid_regs did not cause expected KVM_RUN error: %d\n",
+		    rv);
+	vcpu_state(vm, VCPU_ID)->kvm_valid_regs = 0;
+
+	/* Request setting invalid register set into VCPU. */
+	run->kvm_dirty_regs = INVALID_SYNC_FIELD;
+	rv = _vcpu_run(vm, VCPU_ID);
+	TEST_ASSERT(rv < 0 && errno == EINVAL,
+		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
+		    rv);
+	vcpu_state(vm, VCPU_ID)->kvm_dirty_regs = 0;
+
+	run->kvm_dirty_regs = INVALID_SYNC_FIELD | TEST_SYNC_FIELDS;
+	rv = _vcpu_run(vm, VCPU_ID);
+	TEST_ASSERT(rv < 0 && errno == EINVAL,
+		    "Invalid kvm_dirty_regs did not cause expected KVM_RUN error: %d\n",
+		    rv);
+	vcpu_state(vm, VCPU_ID)->kvm_dirty_regs = 0;
+
 	/* Request and verify all valid register sets. */
 	run->kvm_valid_regs = TEST_SYNC_FIELDS;
 	rv = _vcpu_run(vm, VCPU_ID);
-- 
2.20.1

Re: [GIT PULL 0/8] KVM: s390: extend selftests add more input checks

[Paolo Bonzini]

On 05/09/19 10:40, Janosch Frank wrote:
>   git://git.kernel.org/pub/scm/linux/kernel/git/kvms390/linux.git tags/kvm-s390-next-5.4-1

Pulled, thanks.

Paolo