Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933068AbcDBA5o (ORCPT ); Fri, 1 Apr 2016 20:57:44 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:54698 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933020AbcDBA5h (ORCPT ); Fri, 1 Apr 2016 20:57:37 -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 3.19.y-ckt 161/170] nbd: ratelimit error msgs after socket close Date: Fri, 1 Apr 2016 17:54:07 -0700 Message-Id: <1459558456-24452-162-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1459558456-24452-1-git-send-email-kamal@canonical.com> References: <1459558456-24452-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1665 Lines: 45 3.19.8-ckt18 -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 a98c41f..1012329 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -578,8 +578,8 @@ 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