Wrap kvm_vcpu_exit_request()'s load of vcpu->mode with READ_ONCE() to
ensure the variable is re-loaded from memory, as there is no guarantee the
caller provides the necessary annotations to ensure KVM sees a fresh value,
e.g. the VM-Exit fastpath could theoretically reuse the pre-VM-Enter value.
Suggested-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kvm/x86.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 70219e406987..d38fdb5f90dd 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2124,8 +2124,9 @@ EXPORT_SYMBOL_GPL(kvm_emulate_monitor);
static inline bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)
{
xfer_to_guest_mode_prepare();
- return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) ||
- xfer_to_guest_mode_work_pending();
+
+ return READ_ONCE(vcpu->mode) == EXITING_GUEST_MODE ||
+ kvm_request_pending(vcpu) || xfer_to_guest_mode_work_pending();
}
/*
base-commit: 15e1c3d65975524c5c792fcd59f7d89f00402261
--
2.46.0.295.g3b9ea8a38a-goog
