On Tue, Sep 20, 2011 at 11:31:06 +0800, Wen Congyang wrote:
At 09/15/2011 06:07 PM, Jiri Denemark Write:
Ever since we introduced fake reboot, we call qemuProcessKill as a reaction to SHUTDOWN event. Unfortunately, qemu doesn't guarantee it flushed all internal buffers before sending SHUTDOWN, in which case killing the process forcibly may result in (virtual) disk corruption.
By sending just SIGTERM without SIGKILL we give qemu time to to flush all buffers and exit. Once qemu exits, we will see an EOF on monitor connection and tear down the domain. In case qemu ignores SIGTERM or just hangs there, the process stays running but that's not any different from a possible hang anytime during the shutdown process so I think it's just fine.
With this patch, the domain can not be shutdown, because we add '-no-shutdown' in the command line.
That's a bug in qemu introduced just before 0.14.0 was released (IIRC) and fixed by http://lists.nongnu.org/archive/html/qemu-devel/2011-09/msg01757.html Jirka