From patchwork Wed Dec 16 17:38:45 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamal Mostafa X-Patchwork-Id: 557675 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id 48B871401AD; Thu, 17 Dec 2015 04:47:41 +1100 (AEDT) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1a9GAp-0003iD-9L; Wed, 16 Dec 2015 17:47:35 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.76) (envelope-from ) id 1a9G45-00009Z-Rx for kernel-team@lists.ubuntu.com; Wed, 16 Dec 2015 17:40:37 +0000 Received: from 1.general.kamal.us.vpn ([10.172.68.52] helo=fourier) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.76) (envelope-from ) id 1a9G45-0006WD-1W; Wed, 16 Dec 2015 17:40:37 +0000 Received: from kamal by fourier with local (Exim 4.82) (envelope-from ) id 1a9G42-0005J1-Pi; Wed, 16 Dec 2015 09:40:34 -0800 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 3.19.y-ckt 085/128] iscsi-target: Fix rx_login_comp hang after login failure Date: Wed, 16 Dec 2015 09:38:45 -0800 Message-Id: <1450287568-19808-86-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1450287568-19808-1-git-send-email-kamal@canonical.com> References: <1450287568-19808-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.19 Cc: Sagi Grimberg , Kamal Mostafa , Nicholas Bellinger X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.19.8-ckt12 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Nicholas Bellinger commit ca82c2bded29b38d36140bfa1e76a7bbfcade390 upstream. This patch addresses a case where iscsi_target_do_tx_login_io() fails sending the last login response PDU, after the RX/TX threads have already been started. The case centers around iscsi_target_rx_thread() not invoking allow_signal(SIGINT) before the send_sig(SIGINT, ...) occurs from the failure path, resulting in RX thread hanging indefinately on iscsi_conn->rx_login_comp. Note this bug is a regression introduced by: commit e54198657b65625085834847ab6271087323ffea Author: Nicholas Bellinger Date: Wed Jul 22 23:14:19 2015 -0700 iscsi-target: Fix iscsit_start_kthreads failure OOPs To address this bug, complete ->rx_login_complete for good measure in the failure path, and immediately return from RX thread context if connection state did not actually reach full feature phase (TARG_CONN_STATE_LOGGED_IN). Cc: Sagi Grimberg Signed-off-by: Nicholas Bellinger Signed-off-by: Kamal Mostafa --- drivers/target/iscsi/iscsi_target.c | 13 ++++++++++++- drivers/target/iscsi/iscsi_target_nego.c | 1 + 2 files changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/target/iscsi/iscsi_target.c b/drivers/target/iscsi/iscsi_target.c index 0c508a4..78dda5a 100644 --- a/drivers/target/iscsi/iscsi_target.c +++ b/drivers/target/iscsi/iscsi_target.c @@ -4052,6 +4052,17 @@ reject: return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES, buf); } +static bool iscsi_target_check_conn_state(struct iscsi_conn *conn) +{ + bool ret; + + spin_lock_bh(&conn->state_lock); + ret = (conn->conn_state != TARG_CONN_STATE_LOGGED_IN); + spin_unlock_bh(&conn->state_lock); + + return ret; +} + int iscsi_target_rx_thread(void *arg) { int ret, rc; @@ -4069,7 +4080,7 @@ int iscsi_target_rx_thread(void *arg) * incoming iscsi/tcp socket I/O, and/or failing the connection. */ rc = wait_for_completion_interruptible(&conn->rx_login_comp); - if (rc < 0) + if (rc < 0 || iscsi_target_check_conn_state(conn)) return 0; if (conn->conn_transport->transport_type == ISCSI_INFINIBAND) { diff --git a/drivers/target/iscsi/iscsi_target_nego.c b/drivers/target/iscsi/iscsi_target_nego.c index 092112e..dcb6348 100644 --- a/drivers/target/iscsi/iscsi_target_nego.c +++ b/drivers/target/iscsi/iscsi_target_nego.c @@ -393,6 +393,7 @@ err: if (login->login_complete) { if (conn->rx_thread && conn->rx_thread_active) { send_sig(SIGINT, conn->rx_thread, 1); + complete(&conn->rx_login_comp); kthread_stop(conn->rx_thread); } if (conn->tx_thread && conn->tx_thread_active) {