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=-8.5 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,USER_AGENT_MUTT 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 542A7C04EB8 for ; Mon, 10 Dec 2018 17:39:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 10D7520851 for ; Mon, 10 Dec 2018 17:39:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="QfdbiwQy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 10D7520851 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728890AbeLJRi6 (ORCPT ); Mon, 10 Dec 2018 12:38:58 -0500 Received: from mail-pl1-f194.google.com ([209.85.214.194]:33295 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727057AbeLJRi6 (ORCPT ); Mon, 10 Dec 2018 12:38:58 -0500 Received: by mail-pl1-f194.google.com with SMTP id z23so5580255plo.0; Mon, 10 Dec 2018 09:38:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=hz707KYSnjULRGls5w6XQJ+JzChQr0hSm9QIMsDXICk=; b=QfdbiwQy6RldfvRr+5v1YIaSbczNX2W0wwUxUGQaBy9Oi3Bj2eB9dKnKd2gyxecMev 7W86irwY+xqSIkqkLOaoI42f/GQMMYogPEtixpFc+eFqTZr+c4+erphGi+WDZ3E9IAIp 95P+x/SDCLbvlxP/Xo1WJbIuiaLwI0xa8JtobZDjuSpiC7UmciDyhCZVerXxtBKoLSo2 m/QFGa6uhLXB0Ftc4MvBcFr40mLafLLminhfo9VZsFyO4WjpKEo++ivAw1lYf4uXnbSq 68P9BQxdq7NYsatlBQeUc5zuvrbJMCvw2VC4LcKcKIHeAgAihrXcdEpCC7VXRtq+vrEE fM0g== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=hz707KYSnjULRGls5w6XQJ+JzChQr0hSm9QIMsDXICk=; b=sc+zjuVkSrRAT0g6658uSoc81iUgM+XVy0Y+Lz5DCHcgYXVf5F/4yBoxtE1MxXNfi4 FocgHoY0m/x4eDrW/vpTCGhLtdavJpmxYmHEgygg+x0a7iIT8zG+bQ2Jzl1zSGatlWjH d23XssEmRhfcAFE+JdInvl9n+9AYSXR846uh8TdHheWW83KkulXIe4Nfw0fcxNp+Y8Bw dOPB/vO85Db8jzwti9WMP4/g3txU3d6W0PXu6g3TC8nBIcP0ZXbJNSR72IgvojqmcFgO Y1oNrHvlAzJqkmSv6BbLBnSBi5BP1yGvgH/cpe1geGCKY+vA3RY/r/aisniv71JGFyZx K5DQ== X-Gm-Message-State: AA+aEWZqmDMMModWPv0yO0jXNnySibTWu5Mq1/UsJWY+Tojb9RQqG2Bz LZxuDw6N/hx5XgvOuUcpXPI= X-Google-Smtp-Source: AFSGD/XiH5/O2v2K/a5b7nBINiLufGI/8geS6LenbJbXRNpAQFYuoIZNrQ9U4E+5+LmgtYjwr0l8cA== X-Received: by 2002:a17:902:70c6:: with SMTP id l6mr13238115plt.30.1544463537242; Mon, 10 Dec 2018 09:38:57 -0800 (PST) Received: from xldev-tmpl.dev.purestorage.com ([192.30.188.252]) by smtp.gmail.com with ESMTPSA id e24sm15782588pfi.153.2018.12.10.09.38.56 (version=TLS1_2 cipher=AES128-SHA bits=128/128); Mon, 10 Dec 2018 09:38:56 -0800 (PST) Date: Mon, 10 Dec 2018 10:38:54 -0700 From: Anatoliy Glagolev To: Brian King Cc: aglagolev@purestorage.com, qla2xxx-upstream@qlogic.com, jejb@linux.vnet.ibm.com, martin.petersen@oracle.com, linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Benjamin Herrenschmidt , kmahlkuc@linux.vnet.ibm.com Subject: Re: [PATCH] scsi: qla2xxx: disabling pci error handler early Message-ID: <20181210173853.GA36196@xldev-tmpl.dev.purestorage.com> References: <1544212602-28085-1-git-send-email-glagolig@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks, Brian. Great point. Even for AER, it looks like in-flight error handler completion is not guaranteed on pci_disable_pcie_error_reporting call, so the crash is still possible. It looks like we need to maintain per-pci_dev context and keep track of in-flight callbacks to make a clean fix. I will send a new patch. On Fri, Dec 07, 2018 at 04:00:27PM -0600, Brian King wrote: > On 12/07/2018 01:56 PM, Anatoliy Glagolev wrote: > > qla2x00_disable_board_on_pci_error and pcie error handlers may run > > in parallel. Specifically, I observed qla2xxx_pci_slot_reset running > > at around the same moment as qla2x00_disable_board_on_pci_error. > > If scsi_qla_host_t or qla_hw_data structs are removed before an error > > handler completes, the handler crashes. > > > > This patch disables pcie error handling early in > > qla2x00_disable_board_on_pci_error and in other paths that remove > > those structs. > > While this may fix this issue for PCIe AER, I think you'll still have > the exposure for EEH errors on a Power system, since we don't have > the pci_enable_pcie_error_reporting API wired up to do anything, > nor do we have much ability to do anything with it since its an > attribute of the hardware. > > Is there a way to fix this that doesn't break Power? > > Thanks, > > Brian > > > > > Signed-off-by: Anatoliy Glagolev > > --- > > drivers/scsi/qla2xxx/qla_os.c | 15 +++++++++------ > > 1 file changed, 9 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c > > index e881fce..b8f277a 100644 > > --- a/drivers/scsi/qla2xxx/qla_os.c > > +++ b/drivers/scsi/qla2xxx/qla_os.c > > @@ -2775,9 +2775,6 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) > > return ret; > > } > > > > - /* This may fail but that's ok */ > > - pci_enable_pcie_error_reporting(pdev); > > - > > ha = kzalloc(sizeof(struct qla_hw_data), GFP_KERNEL); > > if (!ha) { > > ql_log_pci(ql_log_fatal, pdev, 0x0009, > > @@ -3039,6 +3036,9 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) > > goto probe_hw_failed; > > } > > > > + /* This may fail but that's ok */ > > + pci_enable_pcie_error_reporting(pdev); > > + > > pci_set_drvdata(pdev, base_vha); > > set_bit(PFLG_DRIVER_PROBING, &base_vha->pci_flags); > > > > @@ -3400,6 +3400,8 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) > > kthread_stop(t); > > } > > > > + pci_disable_pcie_error_reporting(); > > + > > qla2x00_free_device(base_vha); > > scsi_host_put(base_vha->host); > > /* > > @@ -3625,6 +3627,8 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) > > } > > qla2x00_wait_for_hba_ready(base_vha); > > > > + pci_disable_pcie_error_reporting(pdev); > > + > > qla2x00_wait_for_sess_deletion(base_vha); > > > > /* > > @@ -3698,8 +3702,6 @@ static void qla2x00_iocb_work_fn(struct work_struct *work) > > pci_release_selected_regions(ha->pdev, ha->bars); > > kfree(ha); > > > > - pci_disable_pcie_error_reporting(pdev); > > - > > pci_disable_device(pdev); > > } > > > > @@ -5826,6 +5828,8 @@ void qla2x00_relogin(struct scsi_qla_host *vha) > > return; > > } > > > > + pci_disable_pcie_error_reporting(pdev); > > + > > qla2x00_wait_for_sess_deletion(base_vha); > > > > set_bit(UNLOADING, &base_vha->dpc_flags); > > @@ -5866,7 +5870,6 @@ void qla2x00_relogin(struct scsi_qla_host *vha) > > qla2x00_unmap_iobases(ha); > > > > pci_release_selected_regions(ha->pdev, ha->bars); > > - pci_disable_pcie_error_reporting(pdev); > > pci_disable_device(pdev); > > > > /* > > > > > -- > Brian King > Power Linux I/O > IBM Linux Technology Center >