linux-kernel - Re: [PATCH v3] fs: record task name which froze superblock

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

Message-ID: <CACVxJT-O4RspyH7O_eENZCmEv6ZdMt+=A5WRsdag-=5uOSvYew@mail.gmail.com>
Date:	Wed, 4 Mar 2015 18:14:35 +0300
From:	Alexey Dobriyan <adobriyan@...il.com>
To:	Mateusz Guzik <mguzik@...hat.com>
Cc:	Dave Chinner <david@...morbit.com>, Jan Kara <jack@...e.cz>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Al Viro <viro@...iv.linux.org.uk>,
	Linux Kernel <linux-kernel@...r.kernel.org>,
	linux-fsdevel <linux-fsdevel@...r.kernel.org>,
	swhiteho@...hat.com, cluster-devel@...hat.com
Subject: Re: [PATCH v3] fs: record task name which froze superblock

On Mon, Mar 2, 2015 at 7:38 AM, Mateusz Guzik <mguzik@...hat.com> wrote:

> As explained below, this one task name is already very useful and likely
> covers majority of real life use cases.
>
> While working in support we were getting a lot of vmcores where hung task
> detector panicked the kernel because a lot of tasks were blocked
> in UN state trying to write to frozen filesystems. I presume OP has
> similar story.

Yes, the intended "use" case is 1 freezer which hopefully covers
majority of bug reports.

> Some back on forth commuication almost always revealed one process e.g.
> freezing stuff and then blocking itself trying to access it. While we
> could see it blocked, we had no presumptive evidence to pin freezing on
> it. A matching name, while still not 100% conclusive, would be ok enough
> to push the case forward and avoid a rountrip of systemap scripts
> showing freezer process tree.
--
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/