Re: [PATCH] io_uring/rsrc: use io_cache_free() to free node allocated by io_rsrc_node_alloc()

[Jens Axboe <axboe@kernel.dk>]

On 3/31/26 4:45 AM, Jackie Liu wrote:
> From: Jackie Liu <liuyun01@kylinos.cn>
> 
> Replace kfree(node) with io_cache_free() in io_buffer_register_bvec()
> to match all other error paths that free nodes allocated via
> io_rsrc_node_alloc(). The node is allocated through io_cache_alloc()
> internally, so it should be returned to the cache via io_cache_free()
> for proper object reuse.
> 
> Fixes: 27cb27b6d5ea ("io_uring: add support for kernel registered bvecs")
> Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
> ---
>  io_uring/rsrc.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/io_uring/rsrc.c b/io_uring/rsrc.c
> index 4fa59bf89bba..c4a7b29a327c 100644
> --- a/io_uring/rsrc.c
> +++ b/io_uring/rsrc.c
> @@ -961,7 +961,7 @@ int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq,
>  	 */
>  	imu = io_alloc_imu(ctx, blk_rq_nr_phys_segments(rq));
>  	if (!imu) {
> -		kfree(node);
> +		io_cache_free(&ctx->node_cache, node);
>  		ret = -ENOMEM;
>  		goto unlock;
>  	}

People have sent this before, but I usually just dismiss it with being
an error path and it doesn't matter one bit if it stays in cache or just
gets freed outright. But might make sense to apply it just for
consistency's sake - and so I don't get it sent again!

-- 
Jens Axboe