From patchwork Wed Apr 1 18:20:18 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Grover X-Patchwork-Id: 25494 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id D0B04DDD1C for ; Thu, 2 Apr 2009 05:20:43 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759642AbZDASUl (ORCPT ); Wed, 1 Apr 2009 14:20:41 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757169AbZDASUj (ORCPT ); Wed, 1 Apr 2009 14:20:39 -0400 Received: from rcsinet13.oracle.com ([148.87.113.125]:19217 "EHLO rgminet13.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756675AbZDASUh (ORCPT ); Wed, 1 Apr 2009 14:20:37 -0400 Received: from rgminet15.oracle.com (rcsinet15.oracle.com [148.87.113.117]) by rgminet13.oracle.com (Switch-3.3.1/Switch-3.3.1) with ESMTP id n31IKYMW015967 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Wed, 1 Apr 2009 18:20:35 GMT Received: from acsmt707.oracle.com (acsmt707.oracle.com [141.146.40.85]) by rgminet15.oracle.com (Switch-3.3.1/Switch-3.3.1) with ESMTP id n31IKYkM024651; Wed, 1 Apr 2009 18:20:35 GMT Received: from localhost.localdomain (/139.185.48.5) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Wed, 01 Apr 2009 11:20:28 -0700 From: Andy Grover To: netdev@vger.kernel.org Cc: rds-devel@oss.oracle.com Subject: [PATCH 1/3] RDS: Fix m_rs_lock deadlock Date: Wed, 1 Apr 2009 11:20:18 -0700 Message-Id: <1238610020-30361-2-git-send-email-andy.grover@oracle.com> X-Mailer: git-send-email 1.5.6.3 In-Reply-To: <1238610020-30361-1-git-send-email-andy.grover@oracle.com> References: <1238610020-30361-1-git-send-email-andy.grover@oracle.com> X-Source-IP: acsmt707.oracle.com [141.146.40.85] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A09020A.49D3B06E.0094:SCFMA4539814,ss=1,fgs=0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org rs_send_drop_to() is called during socket close. If it takes m_rs_lock without disabling interrupts, then rds_send_remove_from_sock() can run from the rx completion handler and thus deadlock. Signed-off-by: Andy Grover --- net/rds/send.c | 6 +++--- 1 files changed, 3 insertions(+), 3 deletions(-) diff --git a/net/rds/send.c b/net/rds/send.c index 1b37364..104fe03 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -615,7 +615,7 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest) { struct rds_message *rm, *tmp; struct rds_connection *conn; - unsigned long flags; + unsigned long flags, flags2; LIST_HEAD(list); int wake = 0; @@ -651,9 +651,9 @@ void rds_send_drop_to(struct rds_sock *rs, struct sockaddr_in *dest) list_for_each_entry(rm, &list, m_sock_item) { /* We do this here rather than in the loop above, so that * we don't have to nest m_rs_lock under rs->rs_lock */ - spin_lock(&rm->m_rs_lock); + spin_lock_irqsave(&rm->m_rs_lock, flags2); rm->m_rs = NULL; - spin_unlock(&rm->m_rs_lock); + spin_unlock_irqrestore(&rm->m_rs_lock, flags2); /* * If we see this flag cleared then we're *sure* that someone