diff options
author | Sean Christopherson <seanjc@google.com> | 2025-02-26 15:18:09 -0800 |
---|---|---|
committer | Sean Christopherson <seanjc@google.com> | 2025-02-28 15:42:28 -0800 |
commit | 62838fa5eade1b23d546e81e7aab6d4c92ec12f2 (patch) | |
tree | 0a62cbb51af47193ccebd1c21e95a4cbade25902 | |
parent | 75418e222e30440ed9aa6d57b6aba474bcd8b4f1 (diff) |
KVM: selftests: Relax assertion on HLT exits if CPU supports Idle HLT
If the CPU supports Idle HLT, which elides HLT VM-Exits if the vCPU has an
unmasked pending IRQ or NMI, relax the xAPIC IPI test's assertion on the
number of HLT exits to only require that the number of exits is less than
or equal to the number of HLT instructions that were executed. I.e. don't
fail the test if Idle HLT does what it's supposed to do.
Note, unfortunately there's no way to determine if *KVM* supports Idle HLT,
as this_cpu_has() checks raw CPU support, and kvm_cpu_has() checks what can
be exposed to L1, i.e. the latter would check if KVM supports nested Idle
HLT. But, since the assert is purely bonus coverage, checking for CPU
support is good enough.
Cc: Manali Shukla <Manali.Shukla@amd.com>
Tested-by: Manali Shukla <Manali.Shukla@amd.com>
Link: https://lore.kernel.org/r/20250226231809.3183093-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
-rw-r--r-- | tools/testing/selftests/kvm/include/x86/processor.h | 1 | ||||
-rw-r--r-- | tools/testing/selftests/kvm/x86/xapic_ipi_test.c | 13 |
2 files changed, 13 insertions, 1 deletions
diff --git a/tools/testing/selftests/kvm/include/x86/processor.h b/tools/testing/selftests/kvm/include/x86/processor.h index 9d365144ac3e..a968a56dcb6e 100644 --- a/tools/testing/selftests/kvm/include/x86/processor.h +++ b/tools/testing/selftests/kvm/include/x86/processor.h @@ -197,6 +197,7 @@ struct kvm_x86_cpu_feature { #define X86_FEATURE_PAUSEFILTER KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 10) #define X86_FEATURE_PFTHRESHOLD KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 12) #define X86_FEATURE_VGIF KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 16) +#define X86_FEATURE_IDLE_HLT KVM_X86_CPU_FEATURE(0x8000000A, 0, EDX, 30) #define X86_FEATURE_SEV KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 1) #define X86_FEATURE_SEV_ES KVM_X86_CPU_FEATURE(0x8000001F, 0, EAX, 3) diff --git a/tools/testing/selftests/kvm/x86/xapic_ipi_test.c b/tools/testing/selftests/kvm/x86/xapic_ipi_test.c index 574a944763b7..58d5c132ed8e 100644 --- a/tools/testing/selftests/kvm/x86/xapic_ipi_test.c +++ b/tools/testing/selftests/kvm/x86/xapic_ipi_test.c @@ -465,7 +465,18 @@ int main(int argc, char *argv[]) cancel_join_vcpu_thread(threads[0], params[0].vcpu); cancel_join_vcpu_thread(threads[1], params[1].vcpu); - TEST_ASSERT_EQ(data->hlt_count, vcpu_get_stat(params[0].vcpu, halt_exits)); + /* + * If the host support Idle HLT, i.e. KVM *might* be using Idle HLT, + * then the number of HLT exits may be less than the number of HLTs + * that were executed, as Idle HLT elides the exit if the vCPU has an + * unmasked, pending IRQ (or NMI). + */ + if (this_cpu_has(X86_FEATURE_IDLE_HLT)) + TEST_ASSERT(data->hlt_count >= vcpu_get_stat(params[0].vcpu, halt_exits), + "HLT insns = %lu, HLT exits = %lu", + data->hlt_count, vcpu_get_stat(params[0].vcpu, halt_exits)); + else + TEST_ASSERT_EQ(data->hlt_count, vcpu_get_stat(params[0].vcpu, halt_exits)); fprintf(stderr, "Test successful after running for %d seconds.\n" |