Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752092AbdIEPmi (ORCPT ); Tue, 5 Sep 2017 11:42:38 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:39758 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751382AbdIEPmd (ORCPT ); Tue, 5 Sep 2017 11:42:33 -0400 From: =?UTF-8?q?H=C3=A5kon=20Bugge?= To: Santosh Shilimkar , "David S . Miller" Cc: netdev@vger.kernel.org, linux-rdma@vger.kernel.org, rds-devel@oss.oracle.com, linux-kernel@vger.kernel.org, knut.omang@oracle.com, wei.lin.guay@oracle.com Subject: [PATCH net] rds: Fix non-atomic operation on shared flag variable Date: Tue, 5 Sep 2017 17:42:01 +0200 Message-Id: <20170905154201.30198-1-Haakon.Bugge@oracle.com> X-Mailer: git-send-email 2.9.3 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1326 Lines: 35 The bits in m_flags in struct rds_message are used for a plurality of reasons, and from different contexts. To avoid any missing updates to m_flags, use the atomic set_bit() instead of the non-atomic equivalent. Signed-off-by: Håkon Bugge Reviewed-by: Knut Omang Reviewed-by: Wei Lin Guay --- net/rds/send.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/rds/send.c b/net/rds/send.c index 41b9f0f..058a407 100644 --- a/net/rds/send.c +++ b/net/rds/send.c @@ -273,7 +273,7 @@ int rds_send_xmit(struct rds_conn_path *cp) len = ntohl(rm->m_inc.i_hdr.h_len); if (cp->cp_unacked_packets == 0 || cp->cp_unacked_bytes < len) { - __set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); + set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); cp->cp_unacked_packets = rds_sysctl_max_unacked_packets; @@ -829,7 +829,7 @@ static int rds_send_queue_rm(struct rds_sock *rs, struct rds_connection *conn, * throughput hits a certain threshold. */ if (rs->rs_snd_bytes >= rds_sk_sndbuf(rs) / 2) - __set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); + set_bit(RDS_MSG_ACK_REQUIRED, &rm->m_flags); list_add_tail(&rm->m_sock_item, &rs->rs_send_queue); set_bit(RDS_MSG_ON_SOCK, &rm->m_flags); -- 2.9.3