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| author | Sean Christopherson <seanjc@google.com> | 2023-09-27 17:19:55 -0700 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2023-10-12 11:08:59 -0400 |
| commit | 77709820787355f45755fe454e26fca8584ecf40 (patch) | |
| tree | 214e31359783a7d2b7bfba1716d60dbca05ed337 | |
| parent | 60d351f18f7a8acd08964ef1d5c948354a7907be (diff) | |
| download | linux-riscv-keystone-77709820787355f45755fe454e26fca8584ecf40.tar.gz | |
KVM: selftests: Load XSAVE state into untouched vCPU during state test
Expand x86's state test to load XSAVE state into a "dummy" vCPU prior to
KVM_SET_CPUID2, and again with an empty guest CPUID model. Except for
off-by-default features, i.e. AMX, KVM's ABI for KVM_SET_XSAVE is that
userspace is allowed to load xfeatures so long as they are supported by
the host. This is a regression test for a combination of KVM bugs where
the state saved by KVM_GET_XSAVE{2} could not be loaded via KVM_SET_XSAVE
if the saved xstate_bv would load guest-unsupported xfeatures.
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20230928001956.924301-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
| -rw-r--r-- | tools/testing/selftests/kvm/x86_64/state_test.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/tools/testing/selftests/kvm/x86_64/state_test.c b/tools/testing/selftests/kvm/x86_64/state_test.c index df3e93df4343fa..115b2cdf927946 100644 --- a/tools/testing/selftests/kvm/x86_64/state_test.c +++ b/tools/testing/selftests/kvm/x86_64/state_test.c @@ -231,9 +231,9 @@ static void __attribute__((__flatten__)) guest_code(void *arg) int main(int argc, char *argv[]) { 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; @@ -286,6 +286,21 @@ 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. + */ + vcpuN = __vm_vcpu_add(vm, vcpu->id + 1); + vcpu_xsave_set(vcpuN, state->xsave); + + vcpu_init_cpuid(vcpuN, &empty_cpuid); + vcpu_xsave_set(vcpuN, state->xsave); + kvm_x86_state_cleanup(state); memset(®s2, 0, sizeof(regs2)); |