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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2025-07-29 19:22:21 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2025-07-29 19:22:21 -0700 |
| commit | 4dd39ddeb68fbb6d068611f2cc647948dc7dfca0 (patch) | |
| tree | 2daf268154b367b2a2e557dfa43c41d9e3a3e83a /arch/x86/kernel/process.c | |
| parent | 1645f6ab966b828bc160c23626d071914debfa79 (diff) | |
| parent | 5bf2f5119b9e957f773a22f226974166b58cff32 (diff) | |
Merge tag 'x86-cpu-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cpu update from Ingo Molnar:
"Add user-space CPUID faulting support for AMD CPUs"
* tag 'x86-cpu-2025-07-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/CPU/AMD: Add CPUID faulting support
Diffstat (limited to 'arch/x86/kernel/process.c')
| -rw-r--r-- | arch/x86/kernel/process.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/arch/x86/kernel/process.c b/arch/x86/kernel/process.c index a838be04f874..1b7960cf6eb0 100644 --- a/arch/x86/kernel/process.c +++ b/arch/x86/kernel/process.c @@ -334,13 +334,21 @@ DEFINE_PER_CPU(u64, msr_misc_features_shadow); static void set_cpuid_faulting(bool on) { - u64 msrval; - msrval = this_cpu_read(msr_misc_features_shadow); - msrval &= ~MSR_MISC_FEATURES_ENABLES_CPUID_FAULT; - msrval |= (on << MSR_MISC_FEATURES_ENABLES_CPUID_FAULT_BIT); - this_cpu_write(msr_misc_features_shadow, msrval); - wrmsrq(MSR_MISC_FEATURES_ENABLES, msrval); + if (boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) { + u64 msrval; + + msrval = this_cpu_read(msr_misc_features_shadow); + msrval &= ~MSR_MISC_FEATURES_ENABLES_CPUID_FAULT; + msrval |= (on << MSR_MISC_FEATURES_ENABLES_CPUID_FAULT_BIT); + this_cpu_write(msr_misc_features_shadow, msrval); + wrmsrq(MSR_MISC_FEATURES_ENABLES, msrval); + } else if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD) { + if (on) + msr_set_bit(MSR_K7_HWCR, MSR_K7_HWCR_CPUID_USER_DIS_BIT); + else + msr_clear_bit(MSR_K7_HWCR, MSR_K7_HWCR_CPUID_USER_DIS_BIT); + } } static void disable_cpuid(void) |