Check potential faults for CR4.CET setting per Intel SDM. CET can be enabled if and only if CR0.WP==1, i.e. setting CR4.CET=1 faults if CR0.WP==0 and setting CR0.WP=0 fails if CR4.CET==1. Co-developed-by: Sean Christopherson <seanjc@xxxxxxxxxx> Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx> Signed-off-by: Yang Weijiang <weijiang.yang@xxxxxxxxx> --- arch/x86/kvm/x86.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 015fb0ef102c..82b9f14990da 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -993,6 +993,9 @@ int kvm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0) (is_64_bit_mode(vcpu) || kvm_is_cr4_bit_set(vcpu, X86_CR4_PCIDE))) return 1; + if (!(cr0 & X86_CR0_WP) && kvm_is_cr4_bit_set(vcpu, X86_CR4_CET)) + return 1; + static_call(kvm_x86_set_cr0)(vcpu, cr0); kvm_post_set_cr0(vcpu, old_cr0, cr0); @@ -1204,6 +1207,9 @@ int kvm_set_cr4(struct kvm_vcpu *vcpu, unsigned long cr4) return 1; } + if ((cr4 & X86_CR4_CET) && !kvm_is_cr0_bit_set(vcpu, X86_CR0_WP)) + return 1; + static_call(kvm_x86_set_cr4)(vcpu, cr4); kvm_post_set_cr4(vcpu, old_cr4, cr4); -- 2.27.0
