From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ursula Braun Subject: [PATCH V2 net-next 1/3] smc: fix mutex unlocks during link group creation Date: Wed, 18 Oct 2017 16:29:58 +0200 Message-ID: <20171018143000.23884-2-ubraun@linux.vnet.ibm.com> References: <20171018143000.23884-1-ubraun@linux.vnet.ibm.com> Cc: netdev@vger.kernel.org, linux-s390@vger.kernel.org, jwi@linux.vnet.ibm.com, schwidefsky@de.ibm.com, heiko.carstens@de.ibm.com, raspl@linux.vnet.ibm.com, ubraun@linux.vnet.ibm.com To: davem@davemloft.net Return-path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:51267 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751787AbdJROaK (ORCPT ); Wed, 18 Oct 2017 10:30:10 -0400 Received: from pps.filterd (m0098416.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id v9IETJ87044421 for ; Wed, 18 Oct 2017 10:30:09 -0400 Received: from e06smtp13.uk.ibm.com (e06smtp13.uk.ibm.com [195.75.94.109]) by mx0b-001b2d01.pphosted.com with ESMTP id 2dp4ukhcyk-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Wed, 18 Oct 2017 10:30:08 -0400 Received: from localhost by e06smtp13.uk.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Wed, 18 Oct 2017 15:30:06 +0100 In-Reply-To: <20171018143000.23884-1-ubraun@linux.vnet.ibm.com> Sender: netdev-owner@vger.kernel.org List-ID: Link group creation is synchronized with the smc_create_lgr_pending lock. In smc_listen_work() this mutex is sometimes unlocked, even though it has not been locked before. This issue will surface in presence of the SMC rendezvous code. Signed-off-by: Ursula Braun --- net/smc/af_smc.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 745f145d4c4d..70f7640f5090 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -808,7 +808,7 @@ static void smc_listen_work(struct work_struct *work) rc = local_contact; if (rc == -ENOMEM) reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/ - goto decline_rdma; + goto decline_rdma_unlock; } link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK]; @@ -816,7 +816,7 @@ static void smc_listen_work(struct work_struct *work) rc = smc_buf_create(new_smc); if (rc) { reason_code = SMC_CLC_DECL_MEM; - goto decline_rdma; + goto decline_rdma_unlock; } smc_close_init(new_smc); @@ -831,7 +831,7 @@ static void smc_listen_work(struct work_struct *work) buf_desc->mr_rx[SMC_SINGLE_LINK]); if (rc) { reason_code = SMC_CLC_DECL_INTERR; - goto decline_rdma; + goto decline_rdma_unlock; } } } @@ -839,15 +839,15 @@ static void smc_listen_work(struct work_struct *work) rc = smc_clc_send_accept(new_smc, local_contact); if (rc) - goto out_err; + goto out_err_unlock; /* receive SMC Confirm CLC message */ reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc), SMC_CLC_CONFIRM); if (reason_code < 0) - goto out_err; + goto out_err_unlock; if (reason_code > 0) - goto decline_rdma; + goto decline_rdma_unlock; smc_conn_save_peer_info(new_smc, &cclc); if (local_contact == SMC_FIRST_CONTACT) smc_link_save_peer_info(link, &cclc); @@ -855,34 +855,34 @@ static void smc_listen_work(struct work_struct *work) rc = smc_rmb_rtoken_handling(&new_smc->conn, &cclc); if (rc) { reason_code = SMC_CLC_DECL_INTERR; - goto decline_rdma; + goto decline_rdma_unlock; } if (local_contact == SMC_FIRST_CONTACT) { rc = smc_ib_ready_link(link); if (rc) { reason_code = SMC_CLC_DECL_INTERR; - goto decline_rdma; + goto decline_rdma_unlock; } /* QP confirmation over RoCE fabric */ reason_code = smc_serv_conf_first_link(new_smc); if (reason_code < 0) { /* peer is not aware of a problem */ rc = reason_code; - goto out_err; + goto out_err_unlock; } if (reason_code > 0) - goto decline_rdma; + goto decline_rdma_unlock; } smc_tx_init(new_smc); + mutex_unlock(&smc_create_lgr_pending); out_connected: sk_refcnt_debug_inc(newsmcsk); if (newsmcsk->sk_state == SMC_INIT) newsmcsk->sk_state = SMC_ACTIVE; enqueue: - mutex_unlock(&smc_create_lgr_pending); lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING); if (lsmc->sk.sk_state == SMC_LISTEN) { smc_accept_enqueue(&lsmc->sk, newsmcsk); @@ -896,6 +896,8 @@ static void smc_listen_work(struct work_struct *work) sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */ return; +decline_rdma_unlock: + mutex_unlock(&smc_create_lgr_pending); decline_rdma: /* RDMA setup failed, switch back to TCP */ smc_conn_free(&new_smc->conn); @@ -907,6 +909,8 @@ static void smc_listen_work(struct work_struct *work) } goto out_connected; +out_err_unlock: + mutex_unlock(&smc_create_lgr_pending); out_err: newsmcsk->sk_state = SMC_CLOSED; smc_conn_free(&new_smc->conn); -- 2.13.5