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Re: [Qemu-devel] [PATCH v2] main-loop: fix qemu_notify_event for aio_not
Re: [Qemu-devel] [PATCH v2] main-loop: fix qemu_notify_event for aio_notify optimization
Mon, 27 Jul 2015 19:36:51 +0100
On 24 July 2015 at 12:42, Paolo Bonzini <address@hidden> wrote:
> aio_notify can be optimized away, and in fact almost always will. However,
> qemu_notify_event is used in places where this is incorrect---most notably,
> when handling SIGTERM. When aio_notify is optimized away, it is possible that
> QEMU enters a blocking ppoll immediately afterwards and stays there, without
> reaching main_loop_should_exit().
> Fix this by using a bottom half. The bottom half can be optimized too, but
> scheduling it is enough for the ppoll not to block. The hang is thus avoided.
> Reported-by: Peter Maydell <address@hidden>
> Signed-off-by: Paolo Bonzini <address@hidden>
Applied to master, thanks.