From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0D3DDCA9EA0 for ; Fri, 25 Oct 2019 14:01:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DA691222BE for ; Fri, 25 Oct 2019 14:01:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572012091; bh=LTN6V6hmihi+VaoMqArjWGsDY+jF6bjygzvWJgkpK/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=DAqw3CdVT0KPBOdztEAndSlLo91kqJpgIFSPjrg7WKBVhPbeqPSHyO2FTU3UUYvC1 gLHALDdjPpVI1O7aeWcqIYxMUsW9OwQdU0whayROV8lL8Q6H9jkY/rB8gQnYzT8m81 YKFjSSgN8IsOwFUGFzzmMzl0C5sFPzofKVXX/GnU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2505522AbfJYN6U (ORCPT ); Fri, 25 Oct 2019 09:58:20 -0400 Received: from mail.kernel.org ([198.145.29.99]:53474 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2505502AbfJYN6O (ORCPT ); Fri, 25 Oct 2019 09:58:14 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id D40E9222CB; Fri, 25 Oct 2019 13:58:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572011894; bh=LTN6V6hmihi+VaoMqArjWGsDY+jF6bjygzvWJgkpK/Q=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=LePEQpw2NwaR8My8PP+RJ91etq11kwVVze/f6T1clE38poAX3zILV4rFTjhuJhoKn PhXDKi3VNSt054usPUH3zLPoJF4V9Nqvqw3pmLz7zz5qLbJwU3QEzUXfsdB44YWvnD aLNcCNeENhDYoCW1bzsXyppqXM3irqOGqunL8lHA= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Bart Van Assche , Hannes Reinecke , Christoph Hellwig , Laurence Oberman , Jason Gunthorpe , Leon Romanovsky , Doug Ledford , "Martin K . Petersen" , Sasha Levin , linux-rdma@vger.kernel.org Subject: [PATCH AUTOSEL 4.9 06/20] scsi: RDMA/srp: Fix a sleep-in-invalid-context bug Date: Fri, 25 Oct 2019 09:57:46 -0400 Message-Id: <20191025135801.25739-6-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191025135801.25739-1-sashal@kernel.org> References: <20191025135801.25739-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org From: Bart Van Assche [ Upstream commit fd56141244066a6a21ef458670071c58b6402035 ] The previous patch guarantees that srp_queuecommand() does not get invoked while reconnecting occurs. Hence remove the code from srp_queuecommand() that prevents command queueing while reconnecting. This patch avoids that the following can appear in the kernel log: BUG: sleeping function called from invalid context at kernel/locking/mutex.c:747 in_atomic(): 1, irqs_disabled(): 0, pid: 5600, name: scsi_eh_9 1 lock held by scsi_eh_9/5600: #0: (rcu_read_lock){....}, at: [<00000000cbb798c7>] __blk_mq_run_hw_queue+0xf1/0x1e0 Preemption disabled at: [<00000000139badf2>] __blk_mq_delay_run_hw_queue+0x78/0xf0 CPU: 9 PID: 5600 Comm: scsi_eh_9 Tainted: G W 4.15.0-rc4-dbg+ #1 Hardware name: Dell Inc. PowerEdge R720/0VWT90, BIOS 2.5.4 01/22/2016 Call Trace: dump_stack+0x67/0x99 ___might_sleep+0x16a/0x250 [ib_srp] __mutex_lock+0x46/0x9d0 srp_queuecommand+0x356/0x420 [ib_srp] scsi_dispatch_cmd+0xf6/0x3f0 scsi_queue_rq+0x4a8/0x5f0 blk_mq_dispatch_rq_list+0x73/0x440 blk_mq_sched_dispatch_requests+0x109/0x1a0 __blk_mq_run_hw_queue+0x131/0x1e0 __blk_mq_delay_run_hw_queue+0x9a/0xf0 blk_mq_run_hw_queue+0xc0/0x1e0 blk_mq_start_hw_queues+0x2c/0x40 scsi_run_queue+0x18e/0x2d0 scsi_run_host_queues+0x22/0x40 scsi_error_handler+0x18d/0x5f0 kthread+0x11c/0x140 ret_from_fork+0x24/0x30 Reviewed-by: Hannes Reinecke Reviewed-by: Christoph Hellwig Reviewed-by: Laurence Oberman Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Doug Ledford Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/infiniband/ulp/srp/ib_srp.c | 21 ++------------------- 1 file changed, 2 insertions(+), 19 deletions(-) diff --git a/drivers/infiniband/ulp/srp/ib_srp.c b/drivers/infiniband/ulp/srp/ib_srp.c index 74de1ae48d4f7..a3145ae1d66d2 100644 --- a/drivers/infiniband/ulp/srp/ib_srp.c +++ b/drivers/infiniband/ulp/srp/ib_srp.c @@ -2102,7 +2102,6 @@ static void srp_handle_qp_err(struct ib_cq *cq, struct ib_wc *wc, static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd) { struct srp_target_port *target = host_to_target(shost); - struct srp_rport *rport = target->rport; struct srp_rdma_ch *ch; struct srp_request *req; struct srp_iu *iu; @@ -2112,16 +2111,6 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd) u32 tag; u16 idx; int len, ret; - const bool in_scsi_eh = !in_interrupt() && current == shost->ehandler; - - /* - * The SCSI EH thread is the only context from which srp_queuecommand() - * can get invoked for blocked devices (SDEV_BLOCK / - * SDEV_CREATED_BLOCK). Avoid racing with srp_reconnect_rport() by - * locking the rport mutex if invoked from inside the SCSI EH. - */ - if (in_scsi_eh) - mutex_lock(&rport->mutex); scmnd->result = srp_chkready(target->rport); if (unlikely(scmnd->result)) @@ -2183,13 +2172,7 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd) goto err_unmap; } - ret = 0; - -unlock_rport: - if (in_scsi_eh) - mutex_unlock(&rport->mutex); - - return ret; + return 0; err_unmap: srp_unmap_data(scmnd, ch, req); @@ -2211,7 +2194,7 @@ static int srp_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scmnd) ret = SCSI_MLQUEUE_HOST_BUSY; } - goto unlock_rport; + return ret; } /* -- 2.20.1