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Date:   Tue, 12 Sep 2023 12:42:58 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Bartosz Golaszewski <brgl@bgdev.pl>
Cc:     Christoph Lameter <cl@linux.com>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Vlastimil Babka <vbabka@suse.cz>,
        Roman Gushchin <roman.gushchin@linux.dev>,
        Hyeonggon Yoo <42.hyeyoo@gmail.com>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org,
        Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Subject: Re: [PATCH] slab: drop unneeded NULL-pointer check in kfree auto
 cleanup
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References: <20230912082643.13144-1-brgl@bgdev.pl>
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On Tue, Sep 12, 2023 at 10:26:43AM +0200, Bartosz Golaszewski wrote:
> From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
> 
> kfree() already accepts and silently ignores NULL-pointers, there's no
> need to check it when running the auto cleanup routine.

There is, because now the compiler can't help you anymore. Also see:

  https://lkml.kernel.org/r/169451499208.27769.5856056754166699857.tip-bot2@tip-bot2