From patchwork Mon Mar 30 18:44:45 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andy Grover X-Patchwork-Id: 25326 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 BF66ADDEED for ; Tue, 31 Mar 2009 05:46:06 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759029AbZC3SpJ (ORCPT ); Mon, 30 Mar 2009 14:45:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759015AbZC3SpI (ORCPT ); Mon, 30 Mar 2009 14:45:08 -0400 Received: from rcsinet12.oracle.com ([148.87.113.124]:27991 "EHLO rgminet12.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758548AbZC3SpH (ORCPT ); Mon, 30 Mar 2009 14:45:07 -0400 Received: from rgminet15.oracle.com (rcsinet15.oracle.com [148.87.113.117]) by rgminet12.oracle.com (Switch-3.3.1/Switch-3.3.1) with ESMTP id n2UIir6J020873 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Mon, 30 Mar 2009 18:44:54 GMT Received: from acsmt701.oracle.com (acsmt701.oracle.com [141.146.40.71]) by rgminet15.oracle.com (Switch-3.3.1/Switch-3.3.1) with ESMTP id n2UIj4a3011246; Mon, 30 Mar 2009 18:45:06 GMT Received: from localhost.localdomain (/139.185.48.5) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Mon, 30 Mar 2009 18:44:58 +0000 From: Andy Grover To: netdev@vger.kernel.org Cc: rds-devel@oss.oracle.com Subject: [PATCH 1/9] RDS: Fix m_rs_lock deadlock Date: Mon, 30 Mar 2009 11:44:45 -0700 Message-Id: <1238438693-29540-2-git-send-email-andy.grover@oracle.com> X-Mailer: git-send-email 1.5.6.3 In-Reply-To: <1238438693-29540-1-git-send-email-andy.grover@oracle.com> References: <1238438693-29540-1-git-send-email-andy.grover@oracle.com> X-Source-IP: acsmt701.oracle.com [141.146.40.71] X-Auth-Type: Internal IP X-CT-RefId: str=0001.0A090208.49D1132C.01C9: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