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Thu, 29 Oct 2026 07:57:03 -0700 (PDT) Received: from archlinux ([2405:201:ac01:5300:8:4c2:8722:36e0]) by smtp.gmail.com with ESMTPSA id a92af1059eb24-1a7549528ebsm14275350c88.0.2026.10.29.07.57.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 29 Oct 2026 07:57:03 -0700 (PDT) From: Anvik Loitongbam To: Jens Axboe Cc: Pavel Begunkov , Olivier Langlois , Sebastian Andrzej Siewior , io-uring@vger.kernel.org, linux-kernel@vger.kernel.org, Anvik Loitongbam Subject: [PATCH v2] io_uring/napi: clean up list traversal with list_for_each_entry_safe() Date: Thu, 29 Oct 2026 20:17:45 +0530 Message-ID: <20261029144745.23792-1-permissiontogallop@gmail.com> X-Mailer: git-send-email 2.56.0 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Switch both loops to the standard list_for_each_entry_safe() pattern and remove the explanatory comment. Signed-off-by: Anvik Loitongbam --- v2: - Resend as a cleanup rather than a PREEMPT_RT UAF fix. io_uring/napi.c | 14 ++++---------- 1 file changed, 4 insertions(+), 10 deletions(-) diff --git a/io_uring/napi.c b/io_uring/napi.c index 7e698720cd51..d299c89cfc3d 100644 --- a/io_uring/napi.c +++ b/io_uring/napi.c @@ -110,16 +110,10 @@ static int __io_napi_del_id(struct io_ring_ctx *ctx, unsigned int napi_id) static void __io_napi_remove_stale(struct io_ring_ctx *ctx) { - struct io_napi_entry *e; + struct io_napi_entry *e, *next; guard(spinlock)(&ctx->napi_lock); - /* - * list_for_each_entry_safe() is not required as long as: - * 1. list_del_rcu() does not reset the deleted node next pointer - * 2. kfree_rcu() delays the memory freeing until the next quiescent - * state - */ - list_for_each_entry(e, &ctx->napi_list, list) { + list_for_each_entry_safe(e, next, &ctx->napi_list, list) { if (time_after(jiffies, READ_ONCE(e->timeout))) { list_del_rcu(&e->list); hash_del_rcu(&e->node); @@ -264,10 +258,10 @@ void io_napi_init(struct io_ring_ctx *ctx) */ void io_napi_free(struct io_ring_ctx *ctx) { - struct io_napi_entry *e; + struct io_napi_entry *e, *next; guard(spinlock)(&ctx->napi_lock); - list_for_each_entry(e, &ctx->napi_list, list) { + list_for_each_entry_safe(e, next, &ctx->napi_list, list) { hash_del_rcu(&e->node); kfree_rcu(e, rcu); } --