Re: [PATCH v2 2/2] firmware: Avoid deadlock of usermodehelper lock at shutdown

[Ming Lei]

On Thu, May 23, 2013 at 12:28 AM, Takashi Iwai <tiwai@xxxxxxx> wrote:
> When a system goes to reboot/shutdown, it tries to disable the
> usermode helper via usermodehelper_disable().  This might be blocked
> when a driver tries to load a firmware beforehand and it's stuck by
> some reason.  For example, dell_rbu driver loads the firmware in
> non-hotplug mode and waits for user-space clearing the loading sysfs
> flag.  If user-space doesn't clear the flag, it waits forever, thus
> blocks the reboot, too.
>
> As a workaround, in this patch, the firmware class driver registers a
> reboot notifier so that it can abort all pending f/w bufs before
> issuing usermodehelper_disable().
>
> Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>

Acked-by: Ming Lei <ming.lei@xxxxxxxxxxxxx>

thanks,
--
Ming Lei
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