linux-kernel - Re: [PATCH v2 1/2] io_uring: Delete a redundant kfree() call in io_ring_ctx

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Message-ID: <87jzoek4r7.fsf@mailhost.krisman.be>
Date: Fri, 12 Jan 2024 11:25:48 -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 1/2] io_uring: Delete a redundant kfree() call in
 io_ring_ctx_alloc()

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

> From: Markus Elfring <elfring@...rs.sourceforge.net>
> Date: Wed, 10 Jan 2024 20:54:43 +0100
>
> Another useful pointer was not reassigned to the data structure member
> “io_bl” by this function implementation.
> Thus omit a redundant call of the function “kfree” at the end.

Perhaps rewrite this to:

ctx->io_bl is initialized later through IORING_OP_PROVIDE_BUFFERS or
IORING_REGISTER_PBUF_RING later on, so there is nothing to free in the
ctx allocation error path.

Other than that, and for this patch only:

Reviewed-by: Gabriel Krisman Bertazi <krisman@...e.de>

thanks,

>
> Signed-off-by: Markus Elfring <elfring@...rs.sourceforge.net>
> ---
>
> v2:
> A change request by Gabriel Krisman Bertazi was applied here.
>
>
>  io_uring/io_uring.c | 1 -
>  1 file changed, 1 deletion(-)
>
> diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
> index 86761ec623f9..c9a63c39cdd0 100644
> --- a/io_uring/io_uring.c
> +++ b/io_uring/io_uring.c
> @@ -344,7 +344,6 @@ static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
>  err:
>  	kfree(ctx->cancel_table.hbs);
>  	kfree(ctx->cancel_table_locked.hbs);
> -	kfree(ctx->io_bl);
>  	xa_destroy(&ctx->io_bl_xa);
>  	kfree(ctx);
>  	return NULL;
> --
> 2.43.0
>

-- 
Gabriel Krisman Bertazi