From: Sean Christopherson <seanjc@google.com> stable inclusion from stable-v6.6.130 commit 5e8bf325ed12db09dcdc47476cf419a66ba449cf category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/14809 CVE: CVE-2026-43265 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ Upstream commit 45405155d876c326da89162b8173b8cc9ab7ed75 ] WARN if a blocking vCPU is awakened by a valid wake event that KVM can't inject, e.g. because KVM needs to complete a nested VM-enter, or needs to re-inject an exception. For the nested VM-Enter case, KVM is supposed to clear "nested_run_pending" if L1 puts L2 into HLT, i.e. entering HLT "completes" the nested VM-Enter. And for already-injected exceptions, it should be impossible for the vCPU to be in a blocking state if a VM-Exit occurred while an exception was being vectored. Link: https://lore.kernel.org/r/20240607172609.3205077-7-seanjc@google.com Signed-off-by: Sean Christopherson <seanjc@google.com> Stable-dep-of: ead63640d4e7 ("KVM: x86: Ignore -EBUSY when checking nested events from vcpu_block()") Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com> --- arch/x86/kvm/x86.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 7742f38cc266..8464796e4cdc 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -11200,7 +11200,10 @@ static inline int vcpu_block(struct kvm_vcpu *vcpu) * causes a spurious wakeup from HLT). */ if (is_guest_mode(vcpu)) { - if (kvm_check_nested_events(vcpu) < 0) + int r = kvm_check_nested_events(vcpu); + + WARN_ON_ONCE(r == -EBUSY); + if (r < 0) return 0; } -- 2.34.1