From patchwork Thu Jan 2 22:07:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 234613 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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham 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 27885C3276C for ; Thu, 2 Jan 2020 22:46:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F24A3217F4 for ; Thu, 2 Jan 2020 22:46:07 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578005168; bh=tYYuJnqw2Qu4p+aCSfePhowU4FvIn/H2uYj/U0pTY84=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=etmCnaVeBD74g4nDiaOMLAVHl+uzMywUHnKYf2SbOZqTqbSEl86T0tTKVroASaybz hBupGe2huBVgI+Xm8HcrpNapb+FdxtBFShFeKcCgXDkyvx06MPr7NTdtpz07+MRggf m7VraD/9djX7n4slxBnkajcAziqyCOwE459WALHY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730276AbgABWqG (ORCPT ); Thu, 2 Jan 2020 17:46:06 -0500 Received: from mail.kernel.org ([198.145.29.99]:36324 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730010AbgABWbS (ORCPT ); Thu, 2 Jan 2020 17:31:18 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 01AA022B48; Thu, 2 Jan 2020 22:31:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1578004277; bh=tYYuJnqw2Qu4p+aCSfePhowU4FvIn/H2uYj/U0pTY84=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GL+vTllDL4C5aYFlWgp49pGFID9x+0waD/e0Uf0vS3xfA+BLHOYmZa6DrYiEpBDDU RPoxSf5bZgoHgM2yuSfS0Kc2HR871fSzLUwnWqRYauyuFvsIVIVj0JcAGPGJz1xuNT 9ivsbnm0vzjgx/QiRyhkdjt9GofX+Q+sODbZ9t6Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Dick Kennedy , James Smart , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.9 112/171] scsi: lpfc: Fix locking on mailbox command completion Date: Thu, 2 Jan 2020 23:07:23 +0100 Message-Id: <20200102220602.684358442@linuxfoundation.org> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200102220546.960200039@linuxfoundation.org> References: <20200102220546.960200039@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@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 e1e0feb25003..1eb9d5f6cea0 100644 --- a/drivers/scsi/lpfc/lpfc_sli.c +++ b/drivers/scsi/lpfc/lpfc_sli.c @@ -11962,13 +11962,19 @@ 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; } /**