From: Jens Axboe <axboe@kernel.dk>
To: Tejun Heo <tj@kernel.org>
Cc: Josh Boyer <jwboyer@fedoraproject.org>,
Jeff Moyer <jmoyer@redhat.com>,
msnitzer@redhat.com, Li Zefan <lizefan@huawei.com>,
Johannes Weiner <hannes@cmpxchg.org>,
cgroups@vger.kernel.org,
"Linux-Kernel@Vger. Kernel. Org" <linux-kernel@vger.kernel.org>,
"Richard W.M. Jones" <rjones@redhat.com>
Subject: Re: [PATCH block/for-linus] block: blkg_destroy_all() should clear q->root_blkg and ->root_rl.blkg
Date: Tue, 8 Sep 2015 09:35:04 -0600 [thread overview]
Message-ID: <55EF0028.30203@kernel.dk> (raw)
In-Reply-To: <20150908153132.GD13749@mtj.duckdns.org>
On 09/08/2015 09:31 AM, Tejun Heo wrote:
> On Sat, Sep 05, 2015 at 03:47:36PM -0400, Tejun Heo wrote:
>> While making the root blkg unconditional, ec13b1d6f0a0 ("blkcg: always
>> create the blkcg_gq for the root blkcg") removed the part which clears
>> q->root_blkg and ->root_rl.blkg during q exit. This leaves the two
>> pointers dangling after blkg_destroy_all(). blk-throttle exit path
>> performs blkg traversals and dereferences ->root_blkg and can lead to
>> the following oops.
>
> Jens, can you please route this one w/ Richard's tested-by added?
Yup, added, thanks.
--
Jens Axboe
prev parent reply other threads:[~2015-09-08 15:35 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2015-08-30 12:30 __blkg_lookup oops with 4.2-rcX Josh Boyer
2015-08-30 12:30 ` Josh Boyer
2015-08-30 18:04 ` Richard W.M. Jones
2015-09-02 14:53 ` Tejun Heo
[not found] ` <20150902145307.GG22326-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org>
2015-09-02 15:32 ` Tejun Heo
2015-09-02 15:32 ` Tejun Heo
2015-09-04 10:46 ` Richard W.M. Jones
[not found] ` <20150904104602.GN29283-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-09-04 17:13 ` Tejun Heo
2015-09-04 17:13 ` Tejun Heo
[not found] ` <20150904171302.GE25329-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org>
2015-09-04 18:17 ` Richard W.M. Jones
2015-09-04 18:17 ` Richard W.M. Jones
2015-09-04 20:42 ` Richard W.M. Jones
2015-09-04 20:42 ` Richard W.M. Jones
2015-09-05 15:34 ` Richard W.M. Jones
[not found] ` <20150905153439.GA18461-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-09-05 15:48 ` Richard W.M. Jones
2015-09-05 15:48 ` Richard W.M. Jones
[not found] ` <20150905154840.GA19460-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2015-09-05 18:38 ` Tejun Heo
2015-09-05 18:38 ` Tejun Heo
[not found] ` <20150905183801.GA8231-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org>
2015-09-05 19:47 ` [PATCH block/for-linus] block: blkg_destroy_all() should clear q->root_blkg and ->root_rl.blkg Tejun Heo
2015-09-05 19:47 ` Tejun Heo
2015-09-06 8:30 ` Richard W.M. Jones
[not found] ` <20150905194736.GB8231-qYNAdHglDFBN0TnZuCh8vA@public.gmane.org>
2015-09-08 15:31 ` Tejun Heo
2015-09-08 15:31 ` Tejun Heo
2015-09-08 15:35 ` Jens Axboe [this message]
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=55EF0028.30203@kernel.dk \
--to=axboe@kernel.dk \
--cc=cgroups@vger.kernel.org \
--cc=hannes@cmpxchg.org \
--cc=jmoyer@redhat.com \
--cc=jwboyer@fedoraproject.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lizefan@huawei.com \
--cc=msnitzer@redhat.com \
--cc=rjones@redhat.com \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.