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Date: Fri, 12 Jan 2024 16:00:21 +0100
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Subject: Re: [v2 2/2] io_uring: Improve exception handling in
 io_ring_ctx_alloc()
To: Gabriel Krisman Bertazi <krisman@suse.de>, Jens Axboe <axboe@kernel.dk>,
 Pavel Begunkov <asml.silence@gmail.com>, io-uring@vger.kernel.org,
 kernel-janitors@vger.kernel.org
Cc: LKML <linux-kernel@vger.kernel.org>
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 <aa867594-e79d-6d08-a08e-8c9e952b4724@web.de>
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 <87frz2k4jm.fsf@mailhost.krisman.be>
Content-Language: en-GB
From: Markus Elfring <Markus.Elfring@web.de>
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>> The label =E2=80=9Cerr=E2=80=9D was used to jump to a kfree() call desp=
ite of
>> the detail in the implementation of the function =E2=80=9Cio_ring_ctx_a=
lloc=E2=80=9D
>> 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,

I dare to present other development views.


> as kfree can handle NULL pointers just fine,

Yes, this is the case.

Would you dare to categorise such a special function calls as redundant?

May it be skipped in more cases?


> and changes like this becomes churn later when backporting or modifying =
the code.

There are usual opportunities to consider for further collateral evolution=
.

Regards,
Markus