From: Waiman Long <longman@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>,
linux-mm@kvack.org, linux-kernel@vger.kernel.org,
Muchun Song <songmuchun@bytedance.com>
Subject: Re: [PATCH] mm/kmemleak: Prevent soft lockup in kmemleak_scan()'s object iteration loops
Date: Thu, 20 Oct 2022 21:22:14 -0400 [thread overview]
Message-ID: <af778779-77b8-15db-d5dc-36c4992483b3@redhat.com> (raw)
In-Reply-To: <20221020175823.d7aa5cfeefd8673429f42081@linux-foundation.org>
On 10/20/22 20:58, Andrew Morton wrote:
> On Thu, 20 Oct 2022 13:56:19 -0400 Waiman Long <longman@redhat.com> wrote:
>
>> Commit 6edda04ccc7c ("mm/kmemleak: prevent soft lockup in first object
>> iteration loop of kmemleak_scan()") adds cond_resched() in the first
>> object iteration loop of kmemleak_scan(). However, it turns that the
>> 2nd objection iteration loop can still cause soft lockup to happen in
>> some cases. So add a cond_resched() call in the 2nd and 3rd loops as
>> well to prevent that and for completeness.
>>
> Seems reasonable, although not an object of beauty.
>
> We didn't include a Fixes: or cc:stable in 6edda04ccc7c, even though it
> addresses softlockups. I think I'll add a cc:stable to this, with a
> Fixes:6edda04ccc7c. So any kenrel which included 6edda04ccc7c will
> hopefully add this as well.
That sounds good to me. I consider commit 6edda04ccc7c incomplete and
this patch complete it. Technically it can be considered a fix.
Thanks,
Longman
next prev parent reply other threads:[~2022-10-21 1:22 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-10-20 17:56 [PATCH] mm/kmemleak: Prevent soft lockup in kmemleak_scan()'s object iteration loops Waiman Long
2022-10-21 0:58 ` Andrew Morton
2022-10-21 1:22 ` Waiman Long [this message]
2022-10-28 13:59 ` Catalin Marinas
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