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KVM: x86: Supplement __cr4_reserved_bits() with X86_FEATURE_PCID check

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Commit 7a873e455567 ("KVM: selftests: Verify supported CR4 bits can be set
before KVM_SET_CPUID2") reveals that KVM allows to set X86_CR4_PCIDE even
when PCID support is missing:

==== Test Assertion Failure ====
  x86_64/set_sregs_test.c:41: rc
  pid=6956 tid=6956 - Invalid argument
     1	0x000000000040177d: test_cr4_feature_bit at set_sregs_test.c:41
     2	0x00000000004014fc: main at set_sregs_test.c:119
     3	0x00007f2d9346d041: ?? ??:0
     4	0x000000000040164d: _start at ??:?
  KVM allowed unsupported CR4 bit (0x20000)

Add X86_FEATURE_PCID feature check to __cr4_reserved_bits() to make
kvm_is_valid_cr4() fail.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20210201142843.108190-1-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
This commit is contained in:
Vitaly Kuznetsov 2021-02-01 15:28:43 +01:00 committed by Paolo Bonzini
parent b66f9bab12
commit 4683d758f4
1 changed files with 2 additions and 0 deletions
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2
arch/x86/kvm/x86.h
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@ -425,6 +425,8 @@ bool kvm_msr_allowed(struct kvm_vcpu *vcpu, u32 index, u32 type);
__reserved_bits |= X86_CR4_UMIP; \
if (!__cpu_has(__c, X86_FEATURE_VMX)) \
__reserved_bits |= X86_CR4_VMXE; \
if (!__cpu_has(__c, X86_FEATURE_PCID)) \
__reserved_bits |= X86_CR4_PCIDE; \
__reserved_bits; \
})