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| author | Josh Poimboeuf <jpoimboe@kernel.org> | 2023-08-25 00:01:35 -0700 |
|---|---|---|
| committer | Sean Christopherson <seanjc@google.com> | 2023-10-04 15:15:52 -0700 |
| commit | 6f0f23ef76be11bc6ace10df5e807f3542da8772 (patch) | |
| tree | 8332a697a7d0cdae6c7c874b9aaaecd2e71e2880 /arch/x86 | |
| parent | f10a570b093e60c6bd3f210ae909f014f421352a (diff) | |
| download | linux-stable-6f0f23ef76be11bc6ace10df5e807f3542da8772.tar.gz linux-stable-6f0f23ef76be11bc6ace10df5e807f3542da8772.tar.bz2 linux-stable-6f0f23ef76be11bc6ace10df5e807f3542da8772.zip | |
KVM: x86: Add IBPB_BRTYPE support
Add support for the IBPB_BRTYPE CPUID flag, which indicates that IBPB
includes branch type prediction flushing.
Note, like SRSO_NO, advertise support for IBPB_BRTYPE even if it's not
enumerated by in the raw CPUID, i.e. bypass the cpuid_count() in
__kvm_cpu_cap_mask(). Some CPUs that gained support via a uCode patch
don't report IBPB_BRTYPE via CPUID (the kernel forces the flag).
Opportunistically use kvm_cpu_cap_check_and_set() for SRSO_NO instead
of manually querying host support (cpu_feature_enabled() and
boot_cpu_has() yield the same end result in this case).
Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Link: https://lore.kernel.org/r/79d5f5914fb42c2c62418ffbcd78f138645ded21.1692919072.git.jpoimboe@kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Diffstat (limited to 'arch/x86')
| -rw-r--r-- | arch/x86/kvm/cpuid.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 0544e30b4946..8f26a929d510 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -764,8 +764,8 @@ void kvm_set_cpu_caps(void) F(NULL_SEL_CLR_BASE) | F(AUTOIBRS) | 0 /* PrefetchCtlMsr */ ); - if (cpu_feature_enabled(X86_FEATURE_SRSO_NO)) - kvm_cpu_cap_set(X86_FEATURE_SRSO_NO); + kvm_cpu_cap_check_and_set(X86_FEATURE_IBPB_BRTYPE); + kvm_cpu_cap_check_and_set(X86_FEATURE_SRSO_NO); kvm_cpu_cap_init_kvm_defined(CPUID_8000_0022_EAX, F(PERFMON_V2) |