| Message ID | 20220929225203.2234702-6-jmattson@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/6] KVM: x86: Mask off reserved bits in CPUID.80000001H | expand |
On 9/30/22 00:52, Jim Mattson wrote: > KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM > actually supports. CPUID.8000001FH:EBX[31:16] are reserved bits and > should be masked off. > > Fixes: 8765d75329a3 ("KVM: X86: Extend CPUID range to include new leaf") > Signed-off-by: Jim Mattson <jmattson@google.com> > --- > arch/x86/kvm/cpuid.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c > index 576cbcf489ce..58dabc9e54db 100644 > --- a/arch/x86/kvm/cpuid.c > +++ b/arch/x86/kvm/cpuid.c > @@ -1188,7 +1188,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) > entry->eax = entry->ebx = entry->ecx = entry->edx = 0; > } else { > cpuid_entry_override(entry, CPUID_8000_001F_EAX); > - > + entry->ebx &= ~GENMASK(31, 16); > /* > * Enumerate '0' for "PA bits reduction", the adjusted > * MAXPHYADDR is enumerated directly (see 0x80000008). I think 15:12 (number of VMPLs supported) should also be masked off since KVM does not support SEV-SNP. Paolo
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 576cbcf489ce..58dabc9e54db 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -1188,7 +1188,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) entry->eax = entry->ebx = entry->ecx = entry->edx = 0; } else { cpuid_entry_override(entry, CPUID_8000_001F_EAX); - + entry->ebx &= ~GENMASK(31, 16); /* * Enumerate '0' for "PA bits reduction", the adjusted * MAXPHYADDR is enumerated directly (see 0x80000008).
KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM actually supports. CPUID.8000001FH:EBX[31:16] are reserved bits and should be masked off. Fixes: 8765d75329a3 ("KVM: X86: Extend CPUID range to include new leaf") Signed-off-by: Jim Mattson <jmattson@google.com> --- arch/x86/kvm/cpuid.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)