linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Andrew Morton <akpm@linux-foundation.org>
To: Waiman Long <llong@redhat.com>
Cc: Gu Bowen <gubowen5@huawei.com>,
	Catalin Marinas <catalin.marinas@arm.com>,
	stable@vger.kernel.org, linux-mm@kvack.org,
	Lu Jialin <lujialin4@huawei.com>,
	Breno Leitao <leitao@debian.org>
Subject: Re: [PATCH] mm: Fix possible deadlock in console_trylock_spinning
Date: Fri, 1 Aug 2025 20:53:23 -0700	[thread overview]
Message-ID: <20250801205323.70c2fabe5f64d2fb7c64fd94@linux-foundation.org> (raw)
In-Reply-To: <5ca375cd-4a20-4807-b897-68b289626550@redhat.com>

On Fri, 1 Aug 2025 23:09:31 -0400 Waiman Long <llong@redhat.com> wrote:

> > Thanks.
> >
> > There have been a few kmemleak locking fixes lately.
> >
> > I believe this fix is independent from the previous ones:
> >
> > https://lkml.kernel.org/r/20250731-kmemleak_lock-v1-1-728fd470198f@debian.org
> > https://lkml.kernel.org/r/20250728190248.605750-1-longman@redhat.com
> >
> > But can people please check?
> 
> I believe that __printk_safe_enter()/_printk_safe_exit() are for printk 
> internal use only. The proper API to use should be 
> printk_deferred_enter()/printk_deferred_exit() if we want to deferred 
> the printing. Since kmemleak_lock will have been acquired with irq 
> disabled, it meets the condition that printk_deferred_*() APIs can be used.

Gotcha, thanks.

kmemleak;c:__lookup_object() has a lot of callers.  I hope you're
correct that all have local irqs enabled, but I'll ask Gu to verify
that then please send along a new patch which uses
printk_deferred_enter()?



  reply	other threads:[~2025-08-02  3:53 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-07-30  9:49 [PATCH] mm: Fix possible deadlock in console_trylock_spinning Gu Bowen
2025-08-01 22:33 ` Andrew Morton
2025-08-02  3:09   ` Waiman Long
2025-08-02  3:53     ` Andrew Morton [this message]
2025-08-04 12:08       ` Catalin Marinas
2025-08-04 12:34         ` Breno Leitao
2025-08-04 18:28           ` Catalin Marinas
2025-08-05  7:44             ` Gu Bowen
2025-08-06 15:34     ` John Ogness
2025-08-07  3:22       ` Gu Bowen
2025-08-01 23:52 ` Andrew Morton
2025-08-11 14:33   ` Petr Mladek

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=20250801205323.70c2fabe5f64d2fb7c64fd94@linux-foundation.org \
    --to=akpm@linux-foundation.org \
    --cc=catalin.marinas@arm.com \
    --cc=gubowen5@huawei.com \
    --cc=leitao@debian.org \
    --cc=linux-mm@kvack.org \
    --cc=llong@redhat.com \
    --cc=lujialin4@huawei.com \
    --cc=stable@vger.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).