From: Yosry Ahmed <yosry.ahmed@linux.dev>
To: Sean Christopherson <seanjc@google.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>,
kvm@vger.kernel.org, linux-kernel@vger.kernel.org,
Yosry Ahmed <yosryahmed@google.com>,
Yosry Ahmed <yosry.ahmed@linux.dev>
Subject: [PATCH 02/12] KVM: selftests: Extend vmx_set_nested_state_test to cover SVM
Date: Wed, 1 Oct 2025 14:58:06 +0000 [thread overview]
Message-ID: <20251001145816.1414855-3-yosry.ahmed@linux.dev> (raw)
In-Reply-To: <20251001145816.1414855-1-yosry.ahmed@linux.dev>
From: Yosry Ahmed <yosryahmed@google.com>
Add test cases for the validation checks in svm_set_nested_state(), and
allow the test to run with SVM as well as VMX.
Signed-off-by: Yosry Ahmed <yosry.ahmed@linux.dev>
---
tools/testing/selftests/kvm/Makefile.kvm | 2 +-
...d_state_test.c => set_nested_state_test.c} | 122 ++++++++++++++++--
2 files changed, 113 insertions(+), 11 deletions(-)
rename tools/testing/selftests/kvm/x86/{vmx_set_nested_state_test.c => set_nested_state_test.c} (70%)
diff --git a/tools/testing/selftests/kvm/Makefile.kvm b/tools/testing/selftests/kvm/Makefile.kvm
index 148d427ff24be..6582396518b19 100644
--- a/tools/testing/selftests/kvm/Makefile.kvm
+++ b/tools/testing/selftests/kvm/Makefile.kvm
@@ -116,7 +116,7 @@ TEST_GEN_PROGS_x86 += x86/vmx_dirty_log_test
TEST_GEN_PROGS_x86 += x86/vmx_exception_with_invalid_guest_state
TEST_GEN_PROGS_x86 += x86/vmx_msrs_test
TEST_GEN_PROGS_x86 += x86/vmx_invalid_nested_guest_state
-TEST_GEN_PROGS_x86 += x86/vmx_set_nested_state_test
+TEST_GEN_PROGS_x86 += x86/set_nested_state_test
TEST_GEN_PROGS_x86 += x86/vmx_tsc_adjust_test
TEST_GEN_PROGS_x86 += x86/vmx_nested_tsc_scaling_test
TEST_GEN_PROGS_x86 += x86/apic_bus_clock_test
diff --git a/tools/testing/selftests/kvm/x86/vmx_set_nested_state_test.c b/tools/testing/selftests/kvm/x86/set_nested_state_test.c
similarity index 70%
rename from tools/testing/selftests/kvm/x86/vmx_set_nested_state_test.c
rename to tools/testing/selftests/kvm/x86/set_nested_state_test.c
index c4c400d2824c1..98a9cd4873d19 100644
--- a/tools/testing/selftests/kvm/x86/vmx_set_nested_state_test.c
+++ b/tools/testing/selftests/kvm/x86/set_nested_state_test.c
@@ -1,6 +1,6 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * vmx_set_nested_state_test
+ * set_nested_state_test
*
* Copyright (C) 2019, Google LLC.
*
@@ -11,6 +11,7 @@
#include "kvm_util.h"
#include "processor.h"
#include "vmx.h"
+#include "svm_util.h"
#include <errno.h>
#include <linux/kvm.h>
@@ -253,6 +254,104 @@ void test_vmx_nested_state(struct kvm_vcpu *vcpu)
free(state);
}
+static void vcpu_efer_enable_svm(struct kvm_vcpu *vcpu)
+{
+ uint64_t old_efer = vcpu_get_msr(vcpu, MSR_EFER);
+
+ vcpu_set_msr(vcpu, MSR_EFER, old_efer | EFER_SVME);
+}
+
+static void vcpu_efer_disable_svm(struct kvm_vcpu *vcpu)
+{
+ uint64_t old_efer = vcpu_get_msr(vcpu, MSR_EFER);
+
+ vcpu_set_msr(vcpu, MSR_EFER, old_efer & ~EFER_SVME);
+}
+
+void set_default_svm_state(struct kvm_nested_state *state, int size)
+{
+ memset(state, 0, size);
+ state->format = 1;
+ state->size = size;
+ state->hdr.svm.vmcb_pa = 0x3000;
+}
+
+void test_svm_nested_state(struct kvm_vcpu *vcpu)
+{
+ /* Add a page for VMCB. */
+ const int state_sz = sizeof(struct kvm_nested_state) + getpagesize();
+ struct kvm_nested_state *state =
+ (struct kvm_nested_state *)malloc(state_sz);
+
+ vcpu_set_cpuid_feature(vcpu, X86_FEATURE_SVM);
+
+ /* The format must be set to 1. 0 for VMX, 1 for SVM. */
+ set_default_svm_state(state, state_sz);
+ state->format = 0;
+ test_nested_state_expect_einval(vcpu, state);
+
+ /* Invalid flags are rejected, KVM_STATE_NESTED_EVMCS is VMX-only */
+ set_default_svm_state(state, state_sz);
+ state->flags = KVM_STATE_NESTED_EVMCS;
+ test_nested_state_expect_einval(vcpu, state);
+
+ /* If EFER.SVME is clear, GIF must be set and guest mode is disallowed */
+ vcpu_efer_disable_svm(vcpu);
+
+ set_default_svm_state(state, state_sz);
+ state->flags = 0;
+ test_nested_state_expect_einval(vcpu, state);
+
+ state->flags = KVM_STATE_NESTED_GUEST_MODE;
+ test_nested_state_expect_einval(vcpu, state);
+
+ state->flags = KVM_STATE_NESTED_GIF_SET;
+ test_nested_state(vcpu, state);
+
+ /* Enable SVM in the guest EFER. */
+ vcpu_efer_enable_svm(vcpu);
+
+ /* Setting vmcb_pa to a non-aligned address is only fine when not entering guest mode */
+ set_default_svm_state(state, state_sz);
+ state->hdr.svm.vmcb_pa = -1ull;
+ state->flags = 0;
+ test_nested_state(vcpu, state);
+ state->flags = KVM_STATE_NESTED_GUEST_MODE;
+ test_nested_state_expect_einval(vcpu, state);
+
+ /*
+ * Size must be large enough to fit kvm_nested_state and VMCB
+ * only when entering guest mode.
+ */
+ set_default_svm_state(state, state_sz/2);
+ state->flags = 0;
+ test_nested_state(vcpu, state);
+ state->flags = KVM_STATE_NESTED_GUEST_MODE;
+ test_nested_state_expect_einval(vcpu, state);
+
+ /*
+ * Test that if we leave nesting the state reflects that when we get it
+ * again, except for vmcb_pa, which is always returned as 0 when not in
+ * guest mode.
+ */
+ set_default_svm_state(state, state_sz);
+ state->hdr.svm.vmcb_pa = -1ull;
+ state->flags = KVM_STATE_NESTED_GIF_SET;
+ test_nested_state(vcpu, state);
+ vcpu_nested_state_get(vcpu, state);
+ TEST_ASSERT(state->size >= sizeof(*state) && state->size <= state_sz,
+ "Size must be between %ld and %d. The size returned was %d.",
+ sizeof(*state), state_sz, state->size);
+ TEST_ASSERT(state->hdr.svm.vmcb_pa == 0,
+ "vmcb_pa must be 0, but was %llx",
+ state->hdr.svm.vmcb_pa);
+ TEST_ASSERT(state->flags == KVM_STATE_NESTED_GIF_SET,
+ "Flags must be equal to 0x%hx, but was 0x%hx",
+ KVM_STATE_NESTED_GIF_SET, state->flags);
+
+ free(state);
+}
+
int main(int argc, char *argv[])
{
struct kvm_vm *vm;
@@ -261,20 +360,20 @@ int main(int argc, char *argv[])
have_evmcs = kvm_check_cap(KVM_CAP_HYPERV_ENLIGHTENED_VMCS);
+ TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX) ||
+ kvm_cpu_has(X86_FEATURE_SVM));
TEST_REQUIRE(kvm_has_cap(KVM_CAP_NESTED_STATE));
- /*
- * AMD currently does not implement set_nested_state, so for now we
- * just early out.
- */
- TEST_REQUIRE(kvm_cpu_has(X86_FEATURE_VMX));
-
vm = vm_create_with_one_vcpu(&vcpu, NULL);
/*
- * First run tests with VMX disabled to check error handling.
+ * First run tests with VMX/SVM disabled to check error handling.
+ * test_{vmx/svm}_nested_state() will re-enable as needed.
*/
- vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_VMX);
+ if (kvm_cpu_has(X86_FEATURE_VMX))
+ vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_VMX);
+ else
+ vcpu_clear_cpuid_feature(vcpu, X86_FEATURE_SVM);
/* Passing a NULL kvm_nested_state causes a EFAULT. */
test_nested_state_expect_efault(vcpu, NULL);
@@ -303,7 +402,10 @@ int main(int argc, char *argv[])
state.flags = KVM_STATE_NESTED_RUN_PENDING;
test_nested_state_expect_einval(vcpu, &state);
- test_vmx_nested_state(vcpu);
+ if (kvm_cpu_has(X86_FEATURE_VMX))
+ test_vmx_nested_state(vcpu);
+ else
+ test_svm_nested_state(vcpu);
kvm_vm_free(vm);
return 0;
--
2.51.0.618.g983fd99d29-goog
next prev parent reply other threads:[~2025-10-01 14:58 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-10-01 14:58 [PATCH 00/12] Extend test coverage for nested SVM Yosry Ahmed
2025-10-01 14:58 ` [PATCH 01/12] KVM: selftests: Minor improvements to asserts in test_vmx_nested_state() Yosry Ahmed
2025-10-09 21:44 ` Jim Mattson
2025-10-01 14:58 ` Yosry Ahmed [this message]
2025-10-09 22:40 ` [PATCH 02/12] KVM: selftests: Extend vmx_set_nested_state_test to cover SVM Jim Mattson
2025-10-09 23:13 ` Yosry Ahmed
2025-10-01 14:58 ` [PATCH 03/12] KVM: selftests: Extend vmx_close_while_nested_test " Yosry Ahmed
2025-10-09 22:44 ` Jim Mattson
2025-10-01 14:58 ` [PATCH 04/12] KVM: selftests: Extend vmx_nested_tsc_scaling_test " Yosry Ahmed
2025-10-09 22:51 ` Jim Mattson
2025-10-09 23:19 ` Yosry Ahmed
2025-10-01 14:58 ` [PATCH 05/12] KVM: selftests: Remove invalid CR3 test from vmx_tsc_adjust_test Yosry Ahmed
2025-10-09 22:55 ` Jim Mattson
2025-10-09 23:24 ` Yosry Ahmed
2025-10-01 14:58 ` [PATCH 06/12] KVM: selftests: Extend vmx_tsc_adjust_test to cover SVM Yosry Ahmed
2025-10-09 23:27 ` Jim Mattson
2025-10-01 14:58 ` [PATCH 07/12] KVM: selftests: Pass the root HVA directly to nested mapping functions Yosry Ahmed
2025-10-09 23:30 ` Jim Mattson
2025-10-01 14:58 ` [PATCH 08/12] KVM: selftests: Use 'leaf' instead of hugepage to describe EPT entries Yosry Ahmed
2025-10-13 18:34 ` Jim Mattson
2025-10-13 21:41 ` Sean Christopherson
2025-10-13 22:25 ` Yosry Ahmed
2025-10-13 22:58 ` Sean Christopherson
2025-10-13 23:13 ` Yosry Ahmed
2025-10-15 18:20 ` Sean Christopherson
2025-10-01 14:58 ` [PATCH 09/12] KVM: selftests: Move all PTE accesses into nested_create_pte() Yosry Ahmed
2025-10-13 18:41 ` Jim Mattson
2025-10-01 14:58 ` [PATCH 10/12] KVM: selftests: Move EPT-specific init outside nested_create_pte() Yosry Ahmed
2025-10-13 18:52 ` Jim Mattson
2025-10-01 14:58 ` [PATCH 11/12] KVM: selftests: Refactor generic nested mapping outside VMX code Yosry Ahmed
2025-10-13 19:04 ` Jim Mattson
2025-10-01 14:58 ` [PATCH 12/12] KVM: selftests: Extend vmx_dirty_log_test to cover SVM Yosry Ahmed
2025-10-01 17:37 ` [PATCH 00/12] Extend test coverage for nested SVM Yosry Ahmed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20251001145816.1414855-3-yosry.ahmed@linux.dev \
--to=yosry.ahmed@linux.dev \
--cc=kvm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=pbonzini@redhat.com \
--cc=seanjc@google.com \
--cc=yosryahmed@google.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox