The patch below does not apply to the 4.9-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

Possible dependencies:

079f6889818d ("KVM: x86: Mask off reserved bits in CPUID.8000001AH") 382409b4c43e ("kvm: x86: Include CPUID leaf 0x8000001e in kvm's supported CPUID")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 079f6889818dd07903fb36c252532ab47ebb6d48 Mon Sep 17 00:00:00 2001 From: Jim Mattson jmattson@google.com Date: Thu, 29 Sep 2022 15:52:01 -0700 Subject: [PATCH] KVM: x86: Mask off reserved bits in CPUID.8000001AH

KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM actually supports. In the case of CPUID.8000001AH, only three bits are currently defined. The 125 reserved bits should be masked off.

Fixes: 24c82e576b78 ("KVM: Sanitize cpuid") Signed-off-by: Jim Mattson jmattson@google.com Message-Id: 20220929225203.2234702-4-jmattson@google.com Cc: stable@vger.kernel.org Signed-off-by: Paolo Bonzini pbonzini@redhat.com

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 489c028859e1..a0292ba650df 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -1189,6 +1189,9 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function) entry->ecx = entry->edx = 0; break; case 0x8000001a: + entry->eax &= GENMASK(2, 0); + entry->ebx = entry->ecx = entry->edx = 0; + break; case 0x8000001e: break; case 0x8000001F: