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

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:	Thu, 23 May 2013 10:41:21 +0800
From:	Ming Lei <ming.lei@...onical.com>
To:	Takashi Iwai <tiwai@...e.de>
Cc:	Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH v2 2/2] firmware: Avoid deadlock of usermodehelper lock at shutdown

On Thu, May 23, 2013 at 12:28 AM, Takashi Iwai <tiwai@...e.de> 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@...e.de>

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

thanks,
--
Ming Lei
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/