From: Lai Jiangshan laijs@linux.alibaba.com
[ Upstream commit 2c5653caecc4807b8abfe9c41880ac38417be7bf ]
For VMX with EPT, dirty PDPTRs need to be loaded before the next vmentry via vmx_load_mmu_pgd()
But not all paths that call load_pdptrs() will cause vmx_load_mmu_pgd() to be invoked. Normally, kvm_mmu_reset_context() is used to cause KVM_REQ_LOAD_MMU_PGD, but sometimes it is skipped:
* commit d81135a57aa6("KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed") skips kvm_mmu_reset_context() after load_pdptrs() when changing CR0.CD and CR0.NW.
* commit 21823fbda552("KVM: x86: Invalidate all PGDs for the current PCID on MOV CR3 w/ flush") skips KVM_REQ_LOAD_MMU_PGD after load_pdptrs() when rewriting the CR3 with the same value.
* commit a91a7c709600("KVM: X86: Don't reset mmu context when toggling X86_CR4_PGE") skips kvm_mmu_reset_context() after load_pdptrs() when changing CR4.PGE.
Fixes: d81135a57aa6 ("KVM: x86: do not reset mmu if CR0.CD and CR0.NW are changed") Fixes: 21823fbda552 ("KVM: x86: Invalidate all PGDs for the current PCID on MOV CR3 w/ flush") Fixes: a91a7c709600 ("KVM: X86: Don't reset mmu context when toggling X86_CR4_PGE") Signed-off-by: Lai Jiangshan laijs@linux.alibaba.com Message-Id: 20211108124407.12187-2-jiangshanlai@gmail.com Signed-off-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Mathias Krause minipli@grsecurity.net # backport to v5.10.x --- arch/x86/kvm/x86.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index b2378ec80305..038ac5bbdd19 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -794,6 +794,7 @@ int load_pdptrs(struct kvm_vcpu *vcpu, struct kvm_mmu *mmu, unsigned long cr3)
memcpy(mmu->pdptrs, pdpte, sizeof(mmu->pdptrs)); kvm_register_mark_dirty(vcpu, VCPU_EXREG_PDPTR); + kvm_make_request(KVM_REQ_LOAD_MMU_PGD, vcpu);
out: