diff options
author | Kim Phillips <kim.phillips@amd.com> | 2023-01-24 10:33:15 -0600 |
---|---|---|
committer | Borislav Petkov (AMD) <bp@alien8.de> | 2023-01-25 13:06:13 +0100 |
commit | 84168ae786f8a15a7eb0f79d34f20b8d261ce2f5 (patch) | |
tree | c1df51afc3793a3f9ee00bfefe4444a3c47ddc8b /arch/x86/kernel/cpu/amd.c | |
parent | a9dc9ec5a1fafc3d2fe7a7b594eefaeaccf89a6b (diff) |
x86/cpu, kvm: Move X86_FEATURE_LFENCE_RDTSC to its native leaf
The LFENCE always serializing feature bit was defined as scattered
LFENCE_RDTSC and its native leaf bit position open-coded for KVM. Add
it to its newly added CPUID leaf 0x80000021 EAX proper. With
LFENCE_RDTSC in its proper place, the kernel's set_cpu_cap() will
effectively synthesize the feature for KVM going forward.
Also, DE_CFG[1] doesn't need to be set on such CPUs anymore.
[ bp: Massage and merge diff from Sean. ]
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Acked-by: Sean Christopherson <seanjc@google.com>
Link: https://lore.kernel.org/r/20230124163319.2277355-5-kim.phillips@amd.com
Diffstat (limited to 'arch/x86/kernel/cpu/amd.c')
-rw-r--r-- | arch/x86/kernel/cpu/amd.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/amd.c b/arch/x86/kernel/cpu/amd.c index f769d6d08b43..208c2ce8598a 100644 --- a/arch/x86/kernel/cpu/amd.c +++ b/arch/x86/kernel/cpu/amd.c @@ -956,7 +956,7 @@ static void init_amd(struct cpuinfo_x86 *c) init_amd_cacheinfo(c); - if (cpu_has(c, X86_FEATURE_XMM2)) { + if (!cpu_has(c, X86_FEATURE_LFENCE_RDTSC) && cpu_has(c, X86_FEATURE_XMM2)) { /* * Use LFENCE for execution serialization. On families which * don't have that MSR, LFENCE is already serializing. |