Wait for the gofer process in Container.Wait(). #12076
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The linked issue is regarding `runsc run --detach=false` not waiting on the gofer (which is its child process). Because of this, if the container is killed externally via `runsc delete`, then the gofer process becomes a zombie. There is a deadlock because `runsc delete` is waiting for the gofer process to be reaped but the `runsc run` process is stuck waiting for a filesystem lock held by the `runsc delete` process before it can reap it in Container.Destroy(). The fix is to also attempt reaping the child gofer process in Container.Wait(). Notice that this is similar to what Sandbox does. Both Sandbox.Wait() and Sandbox.destroy() call Sandbox.waitForStopped() which reaps the child sandbox process. However, only Container.Destroy() => stop() => waitForStopped(). This change updates Container.Wait() to also call Container.waitForStopped(). This fixes the above deadlock because `runsc run` will reap the gofer before getting stuck waiting for the filesystem lock. Fixes #12051 PiperOrigin-RevId: 798074124
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Wait for the gofer process in Container.Wait().
The linked issue is regarding
runsc run --detach=falsenot waiting on thegofer (which is its child process). Because of this, if the container is killed
externally via
runsc delete, then the gofer process becomes a zombie. Thereis a deadlock because
runsc deleteis waiting for the gofer process to bereaped but the
runsc runprocess is stuck waiting for a filesystem lock heldby the
runsc deleteprocess before it can reap it in Container.Destroy().The fix is to also attempt reaping the child gofer process in Container.Wait().
Notice that this is similar to what Sandbox does. Both Sandbox.Wait() and
Sandbox.destroy() call Sandbox.waitForStopped() which reaps the child sandbox
process. However, only Container.Destroy() => stop() => waitForStopped(). This
change updates Container.Wait() to also call Container.waitForStopped().
This fixes the above deadlock because
runsc runwill reap the gofer beforegetting stuck waiting for the filesystem lock.
Fixes #12051