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-rw-r--r--tools/testing/selftests/kvm/include/ucall_common.h2
-rw-r--r--tools/testing/selftests/kvm/include/x86_64/processor.h23
-rw-r--r--tools/testing/selftests/kvm/lib/guest_sprintf.c7
-rw-r--r--tools/testing/selftests/kvm/lib/test_util.c2
-rw-r--r--tools/testing/selftests/kvm/lib/x86_64/apic.c2
-rw-r--r--tools/testing/selftests/kvm/memslot_perf_test.c9
-rw-r--r--tools/testing/selftests/kvm/riscv/get-reg-list.c58
-rw-r--r--tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c2
-rw-r--r--tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c2
-rwxr-xr-xtools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh1
-rw-r--r--tools/testing/selftests/kvm/x86_64/state_test.c110
-rw-r--r--tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c4
-rw-r--r--tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c4
13 files changed, 184 insertions, 42 deletions
diff --git a/tools/testing/selftests/kvm/include/ucall_common.h b/tools/testing/selftests/kvm/include/ucall_common.h
index 112bc1da732a..ce33d306c2cb 100644
--- a/tools/testing/selftests/kvm/include/ucall_common.h
+++ b/tools/testing/selftests/kvm/include/ucall_common.h
@@ -1,7 +1,5 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
- * tools/testing/selftests/kvm/include/kvm_util.h
- *
* Copyright (C) 2018, Google LLC.
*/
#ifndef SELFTEST_KVM_UCALL_COMMON_H
diff --git a/tools/testing/selftests/kvm/include/x86_64/processor.h b/tools/testing/selftests/kvm/include/x86_64/processor.h
index 4fd042112526..25bc61dac5fb 100644
--- a/tools/testing/selftests/kvm/include/x86_64/processor.h
+++ b/tools/testing/selftests/kvm/include/x86_64/processor.h
@@ -68,6 +68,12 @@ struct xstate {
#define XFEATURE_MASK_OPMASK BIT_ULL(5)
#define XFEATURE_MASK_ZMM_Hi256 BIT_ULL(6)
#define XFEATURE_MASK_Hi16_ZMM BIT_ULL(7)
+#define XFEATURE_MASK_PT BIT_ULL(8)
+#define XFEATURE_MASK_PKRU BIT_ULL(9)
+#define XFEATURE_MASK_PASID BIT_ULL(10)
+#define XFEATURE_MASK_CET_USER BIT_ULL(11)
+#define XFEATURE_MASK_CET_KERNEL BIT_ULL(12)
+#define XFEATURE_MASK_LBR BIT_ULL(15)
#define XFEATURE_MASK_XTILE_CFG BIT_ULL(17)
#define XFEATURE_MASK_XTILE_DATA BIT_ULL(18)
@@ -147,6 +153,7 @@ struct kvm_x86_cpu_feature {
#define X86_FEATURE_CLWB KVM_X86_CPU_FEATURE(0x7, 0, EBX, 24)
#define X86_FEATURE_UMIP KVM_X86_CPU_FEATURE(0x7, 0, ECX, 2)
#define X86_FEATURE_PKU KVM_X86_CPU_FEATURE(0x7, 0, ECX, 3)
+#define X86_FEATURE_OSPKE KVM_X86_CPU_FEATURE(0x7, 0, ECX, 4)
#define X86_FEATURE_LA57 KVM_X86_CPU_FEATURE(0x7, 0, ECX, 16)
#define X86_FEATURE_RDPID KVM_X86_CPU_FEATURE(0x7, 0, ECX, 22)
#define X86_FEATURE_SGX_LC KVM_X86_CPU_FEATURE(0x7, 0, ECX, 30)
@@ -553,6 +560,13 @@ static inline void xsetbv(u32 index, u64 value)
__asm__ __volatile__("xsetbv" :: "a" (eax), "d" (edx), "c" (index));
}
+static inline void wrpkru(u32 pkru)
+{
+ /* Note, ECX and EDX are architecturally required to be '0'. */
+ asm volatile(".byte 0x0f,0x01,0xef\n\t"
+ : : "a" (pkru), "c"(0), "d"(0));
+}
+
static inline struct desc_ptr get_gdt(void)
{
struct desc_ptr gdt;
@@ -908,6 +922,15 @@ static inline bool kvm_pmu_has(struct kvm_x86_pmu_feature feature)
!kvm_cpu_has(feature.anti_feature);
}
+static __always_inline uint64_t kvm_cpu_supported_xcr0(void)
+{
+ if (!kvm_cpu_has_p(X86_PROPERTY_SUPPORTED_XCR0_LO))
+ return 0;
+
+ return kvm_cpu_property(X86_PROPERTY_SUPPORTED_XCR0_LO) |
+ ((uint64_t)kvm_cpu_property(X86_PROPERTY_SUPPORTED_XCR0_HI) << 32);
+}
+
static inline size_t kvm_cpuid2_size(int nr_entries)
{
return sizeof(struct kvm_cpuid2) +
diff --git a/tools/testing/selftests/kvm/lib/guest_sprintf.c b/tools/testing/selftests/kvm/lib/guest_sprintf.c
index c4a69d8aeb68..74627514c4d4 100644
--- a/tools/testing/selftests/kvm/lib/guest_sprintf.c
+++ b/tools/testing/selftests/kvm/lib/guest_sprintf.c
@@ -200,6 +200,13 @@ repeat:
++fmt;
}
+ /*
+ * Play nice with %llu, %llx, etc. KVM selftests only support
+ * 64-bit builds, so just treat %ll* the same as %l*.
+ */
+ if (qualifier == 'l' && *fmt == 'l')
+ ++fmt;
+
/* default base */
base = 10;
diff --git a/tools/testing/selftests/kvm/lib/test_util.c b/tools/testing/selftests/kvm/lib/test_util.c
index 3e36019eeb4a..5d7f28b02d73 100644
--- a/tools/testing/selftests/kvm/lib/test_util.c
+++ b/tools/testing/selftests/kvm/lib/test_util.c
@@ -387,7 +387,7 @@ char *strdup_printf(const char *fmt, ...)
char *str;
va_start(ap, fmt);
- vasprintf(&str, fmt, ap);
+ TEST_ASSERT(vasprintf(&str, fmt, ap) >= 0, "vasprintf() failed");
va_end(ap);
return str;
diff --git a/tools/testing/selftests/kvm/lib/x86_64/apic.c b/tools/testing/selftests/kvm/lib/x86_64/apic.c
index 7168e25c194e..89153a333e83 100644
--- a/tools/testing/selftests/kvm/lib/x86_64/apic.c
+++ b/tools/testing/selftests/kvm/lib/x86_64/apic.c
@@ -1,7 +1,5 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * tools/testing/selftests/kvm/lib/x86_64/processor.c
- *
* Copyright (C) 2021, Google LLC.
*/
diff --git a/tools/testing/selftests/kvm/memslot_perf_test.c b/tools/testing/selftests/kvm/memslot_perf_test.c
index 20eb2e730800..8698d1ab60d0 100644
--- a/tools/testing/selftests/kvm/memslot_perf_test.c
+++ b/tools/testing/selftests/kvm/memslot_perf_test.c
@@ -1033,9 +1033,8 @@ static bool test_loop(const struct test_data *data,
struct test_result *rbestruntime)
{
uint64_t maxslots;
- struct test_result result;
+ struct test_result result = {};
- result.nloops = 0;
if (!test_execute(targs->nslots, &maxslots, targs->seconds, data,
&result.nloops,
&result.slot_runtime, &result.guest_runtime)) {
@@ -1089,7 +1088,7 @@ int main(int argc, char *argv[])
.seconds = 5,
.runs = 1,
};
- struct test_result rbestslottime;
+ struct test_result rbestslottime = {};
int tctr;
if (!check_memory_sizes())
@@ -1098,11 +1097,10 @@ int main(int argc, char *argv[])
if (!parse_args(argc, argv, &targs))
return -1;
- rbestslottime.slottimens = 0;
for (tctr = targs.tfirst; tctr <= targs.tlast; tctr++) {
const struct test_data *data = &tests[tctr];
unsigned int runctr;
- struct test_result rbestruntime;
+ struct test_result rbestruntime = {};
if (tctr > targs.tfirst)
pr_info("\n");
@@ -1110,7 +1108,6 @@ int main(int argc, char *argv[])
pr_info("Testing %s performance with %i runs, %d seconds each\n",
data->name, targs.runs, targs.seconds);
- rbestruntime.runtimens = 0;
for (runctr = 0; runctr < targs.runs; runctr++)
if (!test_loop(data, &targs,
&rbestslottime, &rbestruntime))
diff --git a/tools/testing/selftests/kvm/riscv/get-reg-list.c b/tools/testing/selftests/kvm/riscv/get-reg-list.c
index d8ecacd03ecf..9f99ea42f45f 100644
--- a/tools/testing/selftests/kvm/riscv/get-reg-list.c
+++ b/tools/testing/selftests/kvm/riscv/get-reg-list.c
@@ -12,19 +12,37 @@
#define REG_MASK (KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK)
+static bool isa_ext_cant_disable[KVM_RISCV_ISA_EXT_MAX];
+
bool filter_reg(__u64 reg)
{
+ switch (reg & ~REG_MASK) {
/*
- * Some ISA extensions are optional and not present on all host,
- * but they can't be disabled through ISA_EXT registers when present.
- * So, to make life easy, just filtering out these kind of registers.
+ * Same set of ISA_EXT registers are not present on all host because
+ * ISA_EXT registers are visible to the KVM user space based on the
+ * ISA extensions available on the host. Also, disabling an ISA
+ * extension using corresponding ISA_EXT register does not affect
+ * the visibility of the ISA_EXT register itself.
+ *
+ * Based on above, we should filter-out all ISA_EXT registers.
*/
- switch (reg & ~REG_MASK) {
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_A:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_C:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_D:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_F:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_H:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_I:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_M:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SVPBMT:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SSTC:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SVINVAL:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZIHINTPAUSE:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZICBOM:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZICBOZ:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZBB:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SSAIA:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_V:
+ case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_SVNAPOT:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZBA:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZBS:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZICNTR:
@@ -32,6 +50,15 @@ bool filter_reg(__u64 reg)
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZIFENCEI:
case KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_ZIHPM:
return true;
+ /* AIA registers are always available when Ssaia can't be disabled */
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(siselect):
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio1):
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio2):
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(sieh):
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(siph):
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio1h):
+ case KVM_REG_RISCV_CSR | KVM_REG_RISCV_CSR_AIA | KVM_REG_RISCV_CSR_AIA_REG(iprio2h):
+ return isa_ext_cant_disable[KVM_RISCV_ISA_EXT_SSAIA];
default:
break;
}
@@ -50,24 +77,27 @@ static inline bool vcpu_has_ext(struct kvm_vcpu *vcpu, int ext)
unsigned long value;
ret = __vcpu_get_reg(vcpu, RISCV_ISA_EXT_REG(ext), &value);
- if (ret) {
- printf("Failed to get ext %d", ext);
- return false;
- }
-
- return !!value;
+ return (ret) ? false : !!value;
}
void finalize_vcpu(struct kvm_vcpu *vcpu, struct vcpu_reg_list *c)
{
+ unsigned long isa_ext_state[KVM_RISCV_ISA_EXT_MAX] = { 0 };
struct vcpu_reg_sublist *s;
+ int rc;
+
+ for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++)
+ __vcpu_get_reg(vcpu, RISCV_ISA_EXT_REG(i), &isa_ext_state[i]);
/*
* Disable all extensions which were enabled by default
* if they were available in the risc-v host.
*/
- for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++)
- __vcpu_set_reg(vcpu, RISCV_ISA_EXT_REG(i), 0);
+ for (int i = 0; i < KVM_RISCV_ISA_EXT_MAX; i++) {
+ rc = __vcpu_set_reg(vcpu, RISCV_ISA_EXT_REG(i), 0);
+ if (rc && isa_ext_state[i])
+ isa_ext_cant_disable[i] = true;
+ }
for_each_sublist(c, s) {
if (!s->feature)
@@ -506,10 +536,6 @@ static __u64 base_regs[] = {
KVM_REG_RISCV | KVM_REG_SIZE_U64 | KVM_REG_RISCV_TIMER | KVM_REG_RISCV_TIMER_REG(time),
KVM_REG_RISCV | KVM_REG_SIZE_U64 | KVM_REG_RISCV_TIMER | KVM_REG_RISCV_TIMER_REG(compare),
KVM_REG_RISCV | KVM_REG_SIZE_U64 | KVM_REG_RISCV_TIMER | KVM_REG_RISCV_TIMER_REG(state),
- KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_A,
- KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_C,
- KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_I,
- KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_ISA_EXT | KVM_RISCV_ISA_EXT_M,
KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_V01,
KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_TIME,
KVM_REG_RISCV | KVM_REG_SIZE_ULONG | KVM_REG_RISCV_SBI_EXT | KVM_REG_RISCV_SBI_SINGLE | KVM_RISCV_SBI_EXT_IPI,
diff --git a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
index e446d76d1c0c..6c1278562090 100644
--- a/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/hyperv_svm_test.c
@@ -1,7 +1,5 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * KVM_GET/SET_* tests
- *
* Copyright (C) 2022, Red Hat, Inc.
*
* Tests for Hyper-V extensions to SVM.
diff --git a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c
index 7f36c32fa760..18ac5c1952a3 100644
--- a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c
+++ b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.c
@@ -1,7 +1,5 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * tools/testing/selftests/kvm/nx_huge_page_test.c
- *
* Usage: to be run via nx_huge_page_test.sh, which does the necessary
* environment setup and teardown
*
diff --git a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh
index 0560149e66ed..7cbb409801ee 100755
--- a/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh
+++ b/tools/testing/selftests/kvm/x86_64/nx_huge_pages_test.sh
@@ -4,7 +4,6 @@
# Wrapper script which performs setup and cleanup for nx_huge_pages_test.
# Makes use of root privileges to set up huge pages and KVM module parameters.
#
-# tools/testing/selftests/kvm/nx_huge_page_test.sh
# Copyright (C) 2022, Google LLC.
set -e
diff --git a/tools/testing/selftests/kvm/x86_64/state_test.c b/tools/testing/selftests/kvm/x86_64/state_test.c
index 4c4925a8ab45..88b58aab7207 100644
--- a/tools/testing/selftests/kvm/x86_64/state_test.c
+++ b/tools/testing/selftests/kvm/x86_64/state_test.c
@@ -139,6 +139,83 @@ static void vmx_l1_guest_code(struct vmx_pages *vmx_pages)
static void __attribute__((__flatten__)) guest_code(void *arg)
{
GUEST_SYNC(1);
+
+ if (this_cpu_has(X86_FEATURE_XSAVE)) {
+ uint64_t supported_xcr0 = this_cpu_supported_xcr0();
+ uint8_t buffer[4096];
+
+ memset(buffer, 0xcc, sizeof(buffer));
+
+ set_cr4(get_cr4() | X86_CR4_OSXSAVE);
+ GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSXSAVE));
+
+ xsetbv(0, xgetbv(0) | supported_xcr0);
+
+ /*
+ * Modify state for all supported xfeatures to take them out of
+ * their "init" state, i.e. to make them show up in XSTATE_BV.
+ *
+ * Note off-by-default features, e.g. AMX, are out of scope for
+ * this particular testcase as they have a different ABI.
+ */
+ GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_FP);
+ asm volatile ("fincstp");
+
+ GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_SSE);
+ asm volatile ("vmovdqu %0, %%xmm0" :: "m" (buffer));
+
+ if (supported_xcr0 & XFEATURE_MASK_YMM)
+ asm volatile ("vmovdqu %0, %%ymm0" :: "m" (buffer));
+
+ if (supported_xcr0 & XFEATURE_MASK_AVX512) {
+ asm volatile ("kmovq %0, %%k1" :: "r" (-1ull));
+ asm volatile ("vmovupd %0, %%zmm0" :: "m" (buffer));
+ asm volatile ("vmovupd %0, %%zmm16" :: "m" (buffer));
+ }
+
+ if (this_cpu_has(X86_FEATURE_MPX)) {
+ uint64_t bounds[2] = { 10, 0xffffffffull };
+ uint64_t output[2] = { };
+
+ GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_BNDREGS);
+ GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_BNDCSR);
+
+ /*
+ * Don't bother trying to get BNDCSR into the INUSE
+ * state. MSR_IA32_BNDCFGS doesn't count as it isn't
+ * managed via XSAVE/XRSTOR, and BNDCFGU can only be
+ * modified by XRSTOR. Stuffing XSTATE_BV in the host
+ * is simpler than doing XRSTOR here in the guest.
+ *
+ * However, temporarily enable MPX in BNDCFGS so that
+ * BNDMOV actually loads BND1. If MPX isn't *fully*
+ * enabled, all MPX instructions are treated as NOPs.
+ *
+ * Hand encode "bndmov (%rax),%bnd1" as support for MPX
+ * mnemonics/registers has been removed from gcc and
+ * clang (and was never fully supported by clang).
+ */
+ wrmsr(MSR_IA32_BNDCFGS, BIT_ULL(0));
+ asm volatile (".byte 0x66,0x0f,0x1a,0x08" :: "a" (bounds));
+ /*
+ * Hand encode "bndmov %bnd1, (%rax)" to sanity check
+ * that BND1 actually got loaded.
+ */
+ asm volatile (".byte 0x66,0x0f,0x1b,0x08" :: "a" (output));
+ wrmsr(MSR_IA32_BNDCFGS, 0);
+
+ GUEST_ASSERT_EQ(bounds[0], output[0]);
+ GUEST_ASSERT_EQ(bounds[1], output[1]);
+ }
+ if (this_cpu_has(X86_FEATURE_PKU)) {
+ GUEST_ASSERT(supported_xcr0 & XFEATURE_MASK_PKRU);
+ set_cr4(get_cr4() | X86_CR4_PKE);
+ GUEST_ASSERT(this_cpu_has(X86_FEATURE_OSPKE));
+
+ wrpkru(-1u);
+ }
+ }
+
GUEST_SYNC(2);
if (arg) {
@@ -153,10 +230,11 @@ static void __attribute__((__flatten__)) guest_code(void *arg)
int main(int argc, char *argv[])
{
+ uint64_t *xstate_bv, saved_xstate_bv;
vm_vaddr_t nested_gva = 0;
-
+ struct kvm_cpuid2 empty_cpuid = {};
struct kvm_regs regs1, regs2;
- struct kvm_vcpu *vcpu;
+ struct kvm_vcpu *vcpu, *vcpuN;
struct kvm_vm *vm;
struct kvm_x86_state *state;
struct ucall uc;
@@ -209,6 +287,34 @@ int main(int argc, char *argv[])
/* Restore state in a new VM. */
vcpu = vm_recreate_with_one_vcpu(vm);
vcpu_load_state(vcpu, state);
+
+ /*
+ * Restore XSAVE state in a dummy vCPU, first without doing
+ * KVM_SET_CPUID2, and then with an empty guest CPUID. Except
+ * for off-by-default xfeatures, e.g. AMX, KVM is supposed to
+ * allow KVM_SET_XSAVE regardless of guest CPUID. Manually
+ * load only XSAVE state, MSRs in particular have a much more
+ * convoluted ABI.
+ *
+ * Load two versions of XSAVE state: one with the actual guest
+ * XSAVE state, and one with all supported features forced "on"
+ * in xstate_bv, e.g. to ensure that KVM allows loading all
+ * supported features, even if something goes awry in saving
+ * the original snapshot.
+ */
+ xstate_bv = (void *)&((uint8_t *)state->xsave->region)[512];
+ saved_xstate_bv = *xstate_bv;
+
+ vcpuN = __vm_vcpu_add(vm, vcpu->id + 1);
+ vcpu_xsave_set(vcpuN, state->xsave);
+ *xstate_bv = kvm_cpu_supported_xcr0();
+ vcpu_xsave_set(vcpuN, state->xsave);
+
+ vcpu_init_cpuid(vcpuN, &empty_cpuid);
+ vcpu_xsave_set(vcpuN, state->xsave);
+ *xstate_bv = saved_xstate_bv;
+ vcpu_xsave_set(vcpuN, state->xsave);
+
kvm_x86_state_cleanup(state);
memset(&regs2, 0, sizeof(regs2));
diff --git a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
index 5b669818e39a..59c7304f805e 100644
--- a/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
+++ b/tools/testing/selftests/kvm/x86_64/tsc_scaling_sync.c
@@ -1,10 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * svm_vmcall_test
- *
* Copyright © 2021 Amazon.com, Inc. or its affiliates.
- *
- * Xen shared_info / pvclock testing
*/
#include "test_util.h"
diff --git a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
index 05898ad9f4d9..9ec9ab60b63e 100644
--- a/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
+++ b/tools/testing/selftests/kvm/x86_64/xen_shinfo_test.c
@@ -1,10 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * svm_vmcall_test
- *
* Copyright © 2021 Amazon.com, Inc. or its affiliates.
- *
- * Xen shared_info / pvclock testing
*/
#include "test_util.h"