linux-kernel - Re: [PATCH v2 2/2] io_uring: Improve exception handling in io_ring_ctx

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Message-ID: <87frz2k4jm.fsf@mailhost.krisman.be>
Date: Fri, 12 Jan 2024 11:30:21 -0300
From: Gabriel Krisman Bertazi <krisman@...e.de>
To: Markus Elfring <Markus.Elfring@....de>
Cc: io-uring@...r.kernel.org,  kernel-janitors@...r.kernel.org,  Jens Axboe
 <axboe@...nel.dk>,  Pavel Begunkov <asml.silence@...il.com>,  LKML
 <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH v2 2/2] io_uring: Improve exception handling in
 io_ring_ctx_alloc()

Markus Elfring <Markus.Elfring@....de> writes:

> From: Markus Elfring <elfring@...rs.sourceforge.net>
> Date: Wed, 10 Jan 2024 21:15:48 +0100
>
> The label “err” was used to jump to a kfree() call despite of
> the detail in the implementation of the function “io_ring_ctx_alloc”
> that it was determined already that a corresponding variable contained
> a null pointer because of a failed memory allocation.
>
> 1. Thus use more appropriate labels instead.
>
> 2. Reorder jump targets at the end.
>

As I mentioned on v1, this doesn't do us any good, as kfree can handle
NULL pointers just fine, and changes like this becomes churn later when
backporting or modifying the code.

-- 
Gabriel Krisman Bertazi