Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757088AbcDDXbo (ORCPT ); Mon, 4 Apr 2016 19:31:44 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:35405 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756890AbcDDX3e (ORCPT ); Mon, 4 Apr 2016 19:29:34 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Dan Streetman , Markus Pargmann , Kamal Mostafa Subject: [PATCH 3.13.y-ckt 92/97] nbd: ratelimit error msgs after socket close Date: Mon, 4 Apr 2016 16:26:56 -0700 Message-Id: <1459812421-933-93-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1459812421-933-1-git-send-email-kamal@canonical.com> References: <1459812421-933-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.13 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1666 Lines: 45 3.13.11-ckt38 -stable review patch. If anyone has any objections, please let me know. ---8<------------------------------------------------------------ From: Dan Streetman commit da6ccaaa79caca4f38b540b651238f87215217a2 upstream. Make the "Attempted send on closed socket" error messages generated in nbd_request_handler() ratelimited. When the nbd socket is shutdown, the nbd_request_handler() function emits an error message for every request remaining in its queue. If the queue is large, this will spam a large amount of messages to the log. There's no need for a separate error message for each request, so this patch ratelimits it. In the specific case this was found, the system was virtual and the error messages were logged to the serial port, which overwhelmed it. Fixes: 4d48a542b427 ("nbd: fix I/O hang on disconnected nbds") Signed-off-by: Dan Streetman Signed-off-by: Markus Pargmann Signed-off-by: Kamal Mostafa --- drivers/block/nbd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index b71f439..708b40c 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -581,8 +581,8 @@ static void do_nbd_request(struct request_queue *q) BUG_ON(nbd->magic != NBD_MAGIC); if (unlikely(!nbd->sock)) { - dev_err(disk_to_dev(nbd->disk), - "Attempted send on closed socket\n"); + dev_err_ratelimited(disk_to_dev(nbd->disk), + "Attempted send on closed socket\n"); req->errors++; nbd_end_request(req); spin_lock_irq(q->queue_lock); -- 2.7.4