[PATCH 5.10 106/118] KVM: x86: Mask off reserved bits in CPUID.80000006H

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



From: Jim Mattson <jmattson@xxxxxxxxxx>

commit eeb69eab57c6604ac90b3fd8e5ac43f24a5535b1 upstream.

KVM_GET_SUPPORTED_CPUID should only enumerate features that KVM
actually supports. CPUID.80000006H:EDX[17:16] are reserved bits and
should be masked off.

Fixes: 43d05de2bee7 ("KVM: pass through CPUID(0x80000006)")
Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
Message-Id: <20220929225203.2234702-2-jmattson@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/x86/kvm/cpuid.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -817,7 +817,8 @@ static inline int __do_cpuid_func(struct
 		cpuid_entry_override(entry, CPUID_8000_0001_ECX);
 		break;
 	case 0x80000006:
-		/* L2 cache and TLB: pass through host info. */
+		/* Drop reserved bits, pass host L2 cache and TLB info. */
+		entry->edx &= ~GENMASK(17, 16);
 		break;
 	case 0x80000007: /* Advanced power management */
 		/* invariant TSC is CPUID.80000007H:EDX[8] */





[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux