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 11CCEC00454 for ; Wed, 11 Dec 2019 15:41:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id DCE3622B48 for ; Wed, 11 Dec 2019 15:41:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576078871; bh=ys9FpzFo0o8D1xty71NRiow1xBrNJTDXhBCms8rNtE0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=V2t8Vh4tS7v+sqOwLOurp8+wcrUpraDIoCNgoKErcOlpMZF6w/PqiiI647/ZWpTh3 DIzMgTqsvAnGvTxCnFAoQyKSu34t0Kzg22JgJgJyPq3+cZ0EDrGjeVQEiUTYvkiQK+ Cf6sosWS62xR4HRp73m38WZb/zXkZ2gxiODxyPU0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388352AbfLKPiR (ORCPT ); Wed, 11 Dec 2019 10:38:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:48604 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388267AbfLKPiQ (ORCPT ); Wed, 11 Dec 2019 10:38:16 -0500 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 803D12077B; Wed, 11 Dec 2019 15:38:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576078696; bh=ys9FpzFo0o8D1xty71NRiow1xBrNJTDXhBCms8rNtE0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=K7qNMyrj25/OPa+BRZPQAF1wmoNcJC4rfInAcwrndf8M26daQJZJf5C3LpI3TTcI9 Gp008Au4vQoX7a6yQh6C8kaBo7zoIXX1GqymRHF2tYZRX1AXJhMZ/EH/3TQ4mCMk29 iNx4lYlnJU+qjHfOA+5NFT6JtM+sb9gCn5G8zGBs= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: James Smart , Dick Kennedy , "Martin K . Petersen" , Sasha Levin , linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 02/37] scsi: lpfc: Fix locking on mailbox command completion Date: Wed, 11 Dec 2019 10:37:38 -0500 Message-Id: <20191211153813.24126-2-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191211153813.24126-1-sashal@kernel.org> References: <20191211153813.24126-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: James Smart [ Upstream commit 07b8582430370097238b589f4e24da7613ca6dd3 ] Symptoms were seen of the driver not having valid data for mailbox commands. After debugging, the following sequence was found: The driver maintains a port-wide pointer of the mailbox command that is currently in execution. Once finished, the port-wide pointer is cleared (done in lpfc_sli4_mq_release()). The next mailbox command issued will set the next pointer and so on. The mailbox response data is only copied if there is a valid port-wide pointer. In the failing case, it was seen that a new mailbox command was being attempted in parallel with the completion. The parallel path was seeing the mailbox no long in use (flag check under lock) and thus set the port pointer. The completion path had cleared the active flag under lock, but had not touched the port pointer. The port pointer is cleared after the lock is released. In this case, the completion path cleared the just-set value by the parallel path. Fix by making the calls that clear mbox state/port pointer while under lock. Also slightly cleaned up the error path. Link: https://lore.kernel.org/r/20190922035906.10977-8-jsmart2021@gmail.com Signed-off-by: Dick Kennedy Signed-off-by: James Smart Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/lpfc/lpfc_sli.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/lpfc/lpfc_sli.c b/drivers/scsi/lpfc/lpfc_sli.c index 523a1058078a5..9b8867c023b93 100644 --- a/drivers/scsi/lpfc/lpfc_sli.c +++ b/drivers/scsi/lpfc/lpfc_sli.c @@ -11759,13 +11759,19 @@ send_current_mbox: phba->sli.sli_flag &= ~LPFC_SLI_MBOX_ACTIVE; /* Setting active mailbox pointer need to be in sync to flag clear */ phba->sli.mbox_active = NULL; + if (bf_get(lpfc_trailer_consumed, mcqe)) + lpfc_sli4_mq_release(phba->sli4_hba.mbx_wq); spin_unlock_irqrestore(&phba->hbalock, iflags); /* Wake up worker thread to post the next pending mailbox command */ lpfc_worker_wake_up(phba); + return workposted; + out_no_mqe_complete: + spin_lock_irqsave(&phba->hbalock, iflags); if (bf_get(lpfc_trailer_consumed, mcqe)) lpfc_sli4_mq_release(phba->sli4_hba.mbx_wq); - return workposted; + spin_unlock_irqrestore(&phba->hbalock, iflags); + return false; } /** -- 2.20.1