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@xxxxxxxxxx>
---
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
