diff options
| author | Sean Christopherson <seanjc@google.com> | 2021-06-22 10:56:49 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-07-14 17:06:12 +0200 |
| commit | 88edf696be93ae33b35daef56fd4d0091d433cd8 (patch) | |
| tree | c2f6ed1b6fb52737f5f7691a129c3de4dbef3795 /arch | |
| parent | 66b1a19cfbacdcb0260135643cd7f81ca43f409a (diff) | |
KVM: x86/mmu: Use MMU's role to detect CR4.SMEP value in nested NPT walk
commit ef318b9edf66a082f23d00d79b70c17b4c055a26 upstream.
Use the MMU's role to get its effective SMEP value when injecting a fault
into the guest. When walking L1's (nested) NPT while L2 is active, vCPU
state will reflect L2, whereas NPT uses the host's (L1 in this case) CR0,
CR4, EFER, etc... If L1 and L2 have different settings for SMEP and
L1 does not have EFER.NX=1, this can result in an incorrect PFEC.FETCH
when injecting #NPF.
Fixes: e57d4a356ad3 ("KVM: Add instruction fetch checking when walking guest page table")
Cc: stable@vger.kernel.org
Signed-off-by: Sean Christopherson <seanjc@google.com>
Message-Id: <20210622175739.3610207-5-seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/mmu/paging_tmpl.h | 3 |
1 files changed, 1 insertions, 2 deletions
diff --git a/arch/x86/kvm/mmu/paging_tmpl.h b/arch/x86/kvm/mmu/paging_tmpl.h index 823a5919f9fa..52fffd68b522 100644 --- a/arch/x86/kvm/mmu/paging_tmpl.h +++ b/arch/x86/kvm/mmu/paging_tmpl.h @@ -471,8 +471,7 @@ retry_walk: error: errcode |= write_fault | user_fault; - if (fetch_fault && (mmu->nx || - kvm_read_cr4_bits(vcpu, X86_CR4_SMEP))) + if (fetch_fault && (mmu->nx || mmu->mmu_role.ext.cr4_smep)) errcode |= PFERR_FETCH_MASK; walker->fault.vector = PF_VECTOR; |