diff options
-rw-r--r-- | pkg/sentry/platform/kvm/machine.go | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/pkg/sentry/platform/kvm/machine.go b/pkg/sentry/platform/kvm/machine.go index 7d92e16cc..679087e25 100644 --- a/pkg/sentry/platform/kvm/machine.go +++ b/pkg/sentry/platform/kvm/machine.go @@ -426,7 +426,12 @@ func (c *vCPU) unlock() { // Normal state. case vCPUUser | vCPUGuest | vCPUWaiter: // Force a transition: this must trigger a notification when we - // return from guest mode. + // return from guest mode. We must clear vCPUWaiter here + // anyways, because BounceToKernel will force a transition only + // from ring3 to ring0, which will not clear this bit. Halt may + // workaround the issue, but if there is no exception or + // syscall in this period, BounceToKernel will hang. + atomicbitops.AndUint32(&c.state, ^vCPUWaiter) c.notify() case vCPUUser | vCPUWaiter: // Waiting for the lock to be released; the responsibility is |