From: David Miller <davem@davemloft.net>
To: sboyd@codeaurora.org
Cc: linux-kernel@vger.kernel.org, netdev@vger.kernel.org,
tj@kernel.org, ben-linux@fluff.org
Subject: Re: [PATCH 2/2] ks8851: Fix mutex deadlock in ks8851_net_stop()
Date: Sat, 21 Apr 2012 15:34:40 -0400 (EDT) [thread overview]
Message-ID: <20120421.153440.1754750876890229323.davem@davemloft.net> (raw)
In-Reply-To: <1334805958-29119-2-git-send-email-sboyd@codeaurora.org>
From: Stephen Boyd <sboyd@codeaurora.org>
Date: Wed, 18 Apr 2012 20:25:58 -0700
> There is a potential deadlock scenario when the ks8851 driver
> is removed. The interrupt handler schedules a workqueue which
> acquires a mutex that ks8851_net_stop() also acquires before
> flushing the workqueue. Previously lockdep wouldn't be able
> to find this problem but now that it has the support we can
> trigger this lockdep warning by rmmoding the driver after
> an ifconfig up.
>
> Fix the possible deadlock by disabling the interrupts in
> the chip and then release the lock across the workqueue
> flushing. The mutex is only there to proect the registers
> anyway so this should be ok.
...
> Cc: Ben Dooks <ben-linux@fluff.org>
> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Applied.
next prev parent reply other threads:[~2012-04-21 19:34 UTC|newest]
Thread overview: 19+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-04-19 3:25 [PATCH 1/2] workqueue: Catch more locking problems with flush_work() Stephen Boyd
2012-04-19 3:25 ` [PATCH 2/2] ks8851: Fix mutex deadlock in ks8851_net_stop() Stephen Boyd
2012-04-21 19:34 ` David Miller [this message]
2012-04-19 8:10 ` [PATCH 1/2] workqueue: Catch more locking problems with flush_work() Yong Zhang
2012-04-19 18:36 ` Stephen Boyd
2012-04-20 5:26 ` Yong Zhang
2012-04-20 6:01 ` Yong Zhang
2012-04-20 6:26 ` Stephen Boyd
2012-04-20 7:18 ` Yong Zhang
2012-04-20 8:18 ` Stephen Boyd
2012-04-20 8:32 ` Yong Zhang
2012-04-21 0:32 ` Yong Zhang
2012-04-19 15:28 ` Tejun Heo
2012-04-19 18:10 ` Stephen Boyd
2012-04-20 17:35 ` Tejun Heo
2012-04-20 23:15 ` Stephen Boyd
2012-04-21 0:28 ` [PATCHv2] " Stephen Boyd
2012-04-21 0:34 ` Yong Zhang
2012-04-23 18:07 ` Tejun Heo
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20120421.153440.1754750876890229323.davem@davemloft.net \
--to=davem@davemloft.net \
--cc=ben-linux@fluff.org \
--cc=linux-kernel@vger.kernel.org \
--cc=netdev@vger.kernel.org \
--cc=sboyd@codeaurora.org \
--cc=tj@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).