Date: Wed, 9 Dec 2015 11:27:44 -0500
From: Tejun Heo <tj@kernel.org>
To: Nikolay Borisov <kernel@kyup.com>
Cc: "Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>,
        SiteGround Operations <operations@siteground.com>
Subject: Re: corruption causing crash in __queue_work
Message-ID: <20151209162744.GN30240@mtj.duckdns.org>
References: <566819D8.5090804@kyup.com>
 <20151209160803.GK30240@mtj.duckdns.org>
 <56685573.1020805@kyup.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <56685573.1020805@kyup.com>
User-Agent: Mutt/1.5.24 (2015-08-30)
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 860
Lines: 22

Hello,

On Wed, Dec 09, 2015 at 06:23:15PM +0200, Nikolay Borisov wrote:
> I think we are seeing this at least daily on at least 1 server (we have
> multiple servers like that). So adding printk's would likely be the way
> to go, anything in particular you might be interested in knowing? I see
> RCU stuff around so might be tricky race condition.

Printing out the workqueue's pointer, name, pwq's pointer, the node
being installed for and the installed pointer should give us enough
clues.  There's RCU involved but the pointers shouldn't be becoming
NULLs unless we're installing NULL ptrs.

Thanks.

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