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charset="UTF-8" Force the vCPU out of L2 if loading CR3 load at the end of setting nested state fails, otherwise KVM will leave the vCPU in a half-baked state, e.g. with L1's page walker, and if nested NPT is disabled, L1's PGD as well. Fixes: e1779c2714c3 ("KVM: x86: nSVM: fix potential NULL derefernce on nested migration") Cc: stable@vger.kernel.org Reported-by: Stefan Teodorescu Reported-by: Sashiko Bot Closes: https://lore.kernel.org/all/sashiko-outbox-210535@kernel.org Closes: https://lore.kernel.org/all/sashiko-outbox-205939@kernel.org Signed-off-by: Sean Christopherson --- arch/x86/kvm/svm/nested.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 07554089ec05..4b1cdc7798bb 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -2114,8 +2114,10 @@ static int svm_set_nested_state(struct kvm_vcpu *vcpu, */ ret = nested_svm_load_cr3(&svm->vcpu, vcpu->arch.cr3, nested_npt_enabled(svm), false); - if (ret) + if (ret) { + svm_leave_nested(vcpu); goto out_free; + } svm->nested.force_msr_bitmap_recalc = true; base-commit: d21eef2084a9af87ac2a783bc7c2b175ba114e4e -- 2.56.1.703.gf848ed807c-goog