All of lore.kernel.org
 help / color / mirror / Atom feed
From: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
To: akpm@linux-foundation.org
Cc: peterz@infradead.org, mingo@redhat.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 (RESEND)] lockdep: Fix fs_reclaim warning.
Date: Fri, 9 Mar 2018 00:30:37 +0900	[thread overview]
Message-ID: <201803090030.JGG56208.FMOOFOJFLQVSHt@I-love.SAKURA.ne.jp> (raw)
In-Reply-To: <20180307153305.16e5225d8a14d96436235eb1@linux-foundation.org>

Andrew Morton wrote:
> On Wed, 28 Feb 2018 06:50:02 +0900 Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> wrote:
> 
> > 
> > This warning is caused by commit d92a8cfcb37ecd13 ("locking/lockdep: Rework
> > FS_RECLAIM annotation") which replaced lockdep_set_current_reclaim_state()/
> > lockdep_clear_current_reclaim_state() in __perform_reclaim() and
> > lockdep_trace_alloc() in slab_pre_alloc_hook() with fs_reclaim_acquire()/
> > fs_reclaim_release(). Since __kmalloc_reserve() from __alloc_skb() adds
> > __GFP_NOMEMALLOC | __GFP_NOWARN to gfp_mask, and all reclaim path simply
> > propagates __GFP_NOMEMALLOC, fs_reclaim_acquire() in slab_pre_alloc_hook()
> > is trying to grab the 'fake' lock again when __perform_reclaim() already
> > grabbed the 'fake' lock.
> 
> That's quite an audit trail.
> 
> Shouldn't we be doing a cc:stable here?  If so, which patch do we
> identify as being fixed, with "Fixes:"?  d92a8cfcb37ecd13, I assume?

Yes please, if you think this patch qualifies for backport.

The test was outdated since v2.6.31, but only v4.14+ seems to trigger this warning.
Thus, I think it is OK to add:

  Fixes: d92a8cfcb37ecd13 ("locking/lockdep: Rework FS_RECLAIM annotation")
  Cc: <stable@vger.kernel.org> # v4.14+

> 
> I'd never even noticed fs_reclaim_acquire() and friends before.  I do
> wish they had "lockdep" in their names, and a comment to explain what
> they do and why they exist.

      reply	other threads:[~2018-03-08 15:31 UTC|newest]

Thread overview: 35+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-01-24  1:36 [4.15-rc9] fs_reclaim lockdep trace Dave Jones
2018-01-24  1:36 ` Dave Jones
2018-01-27 22:24 ` Dave Jones
2018-01-27 22:24   ` Dave Jones
2018-01-27 22:43   ` Linus Torvalds
2018-01-27 22:43     ` Linus Torvalds
2018-01-28  1:16     ` Tetsuo Handa
2018-01-28  1:16       ` Tetsuo Handa
2018-01-28  4:25       ` Tetsuo Handa
2018-01-28  4:25         ` Tetsuo Handa
2018-01-28  5:55         ` Tetsuo Handa
2018-01-28  5:55           ` Tetsuo Handa
2018-01-28  5:55           ` Tetsuo Handa
2018-01-29  2:43           ` Dave Jones
2018-01-29  2:43             ` Dave Jones
2018-01-29 10:27           ` Peter Zijlstra
2018-01-29 10:27             ` Peter Zijlstra
2018-01-29 11:47             ` Tetsuo Handa
2018-01-29 11:47               ` Tetsuo Handa
2018-01-29 13:55               ` Peter Zijlstra
2018-01-29 13:55                 ` Peter Zijlstra
2018-02-01 11:36                 ` Tetsuo Handa
2018-02-01 11:36                   ` Tetsuo Handa
2018-02-08 11:43                   ` [PATCH v2] lockdep: Fix fs_reclaim warning Tetsuo Handa
2018-02-08 11:43                     ` Tetsuo Handa
2018-02-12 12:08                     ` Nikolay Borisov
2018-02-12 12:08                       ` Nikolay Borisov
2018-02-12 13:46                       ` Tetsuo Handa
2018-02-12 13:46                         ` Tetsuo Handa
2018-02-19 11:52                     ` Tetsuo Handa
2018-02-19 11:52                       ` Tetsuo Handa
2018-02-27 21:50                     ` [PATCH v2 (RESEND)] " Tetsuo Handa
2018-03-07 21:44                       ` Tetsuo Handa
2018-03-07 23:33                       ` Andrew Morton
2018-03-08 15:30                         ` Tetsuo Handa [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=201803090030.JGG56208.FMOOFOJFLQVSHt@I-love.SAKURA.ne.jp \
    --to=penguin-kernel@i-love.sakura.ne.jp \
    --cc=akpm@linux-foundation.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mingo@redhat.com \
    --cc=peterz@infradead.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.