Previously, KVM reported support for CPUID.(EAX=7,ECX=1) only if the
maximum leaf 7 index on the host was exactly 1. A recent microcode
patch for Ice Lake raised the maximum leaf 7 index from 0 to 2,
skipping right over 1. Though that patch left CPUID.(EAX=7,ECX=1)
filled with zeros on Ice Lake, it nonetheless exposed this bug.
Report CPUID.(EAX=7,ECX=1) support if the maximum leaf 7 index on the
host is at least 1.
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
Fixes: bcf600ca8d21 ("KVM: x86: Remove the unnecessary loop on CPUID 0x7 sub-leafs")
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 07be45c5bb93..64cdabb3cb2c 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -886,7 +886,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
cpuid_entry_override(entry, CPUID_7_EDX);
/* KVM only supports 0x7.0 and 0x7.1, capped above via min(). */
- if (entry->eax == 1) {
+ if (entry->eax >= 1) {
entry = do_host_cpuid(array, function, 1);
if (!entry)
goto out;
--
2.37.2.672.g94769d06f0-goog
