[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <b90aac4c-7116-d872-4854-9cd012145061@kernel.dk>
Date: Wed, 27 Jul 2016 08:45:24 -0600
From: Jens Axboe <axboe@...nel.dk>
To: Paolo Valente <paolo.valente@...aro.org>, Tejun Heo <tj@...nel.org>
Cc: linux-block@...r.kernel.org, linux-kernel@...r.kernel.org,
ulf.hansson@...aro.org, linus.walleij@...aro.org,
broonie@...nel.org, stable@...r.kernel.org, jmoyer@...hat.com,
Nikolay Borisov <kernel@...p.com>
Subject: Re: [PATCH BUGFIX V5] block: add missing group association in
bio-cloning functions
On 07/26/2016 11:22 PM, Paolo Valente wrote:
> When a bio is cloned, the newly created bio must be associated with
> the same blkcg as the original bio (if BLK_CGROUP is enabled). If
> this operation is not performed, then the new bio is not associated
> with any group, and the group of the current task is returned when
> the group of the bio is requested.
>
> Depending on the cloning frequency, this may cause a large
> percentage of the bios belonging to a given group to be treated
> as if belonging to other groups (in most cases as if belonging to
> the root group). The expected group isolation may thereby be broken.
>
> This commit adds the missing association in bio-cloning functions.
Added for 4.8, thanks.
--
Jens Axboe
Powered by blists - more mailing lists