Commit 427890af authored Aug 17, 2020 by Jim Mattson Committed by Paolo Bonzini Aug 17, 2020

kvm: x86: Toggling CR4.SMAP does not load PDPTEs in PAE mode



See the SDM, volume 3, section 4.4.1:

If PAE paging would be in use following an execution of MOV to CR0 or
MOV to CR4 (see Section 4.1.1) and the instruction is modifying any of
CR0.CD, CR0.NW, CR0.PG, CR4.PAE, CR4.PGE, CR4.PSE, or CR4.SMEP; then
the PDPTEs are loaded from the address in CR3.

Fixes: 0be0226f ("KVM: MMU: fix SMAP virtualization")
Cc: Xiao Guangrong <guangrong.xiao@linux.intel.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Reviewed-by: Oliver Upton <oupton@google.com>
Message-Id: <20200817181655.3716509-2-jmattson@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

parent 19cf4b7e

arch/x86/kvm/x86.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -975,7 +975,7 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4)
		{
		unsigned long old_cr4 = kvm_read_cr4(vcpu);
		unsigned long pdptr_bits = X86_CR4_PGE \| X86_CR4_PSE \| X86_CR4_PAE \|
		X86_CR4_SMEP \| X86_CR4_SMAP \| X86_CR4_PKE;
		X86_CR4_SMEP \| X86_CR4_PKE;

		if (kvm_valid_cr4(vcpu, cr4))
		return 1;

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