From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964796AbcCDQGM (ORCPT ); Fri, 4 Mar 2016 11:06:12 -0500 Received: from wtarreau.pck.nerim.net ([62.212.114.60]:60774 "EHLO 1wt.eu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759523AbcCDQFs (ORCPT ); Fri, 4 Mar 2016 11:05:48 -0500 Message-Id: <20160304153001.579998776@1wt.eu> User-Agent: quilt/0.63-1 Date: Fri, 04 Mar 2016 16:30:20 +0100 From: Willy Tarreau To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Alan Stern , Paul Menzel , Erich Schubert , Alexandre Rossi , James Bottomley , Ben Hutchings , Willy Tarreau Subject: [PATCH 2.6.32 20/55] SCSI: fix crashes in sd and sr runtime PM MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 In-Reply-To: <148ee355b419e9976ca727513a1405c8@local> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.32-longterm review patch. If anyone has any objections, please let me know. ------------------ From: Alan Stern commit 13b4389143413a1f18127c07f72c74cad5b563e8 upstream. Runtime suspend during driver probe and removal can cause problems. The driver's runtime_suspend or runtime_resume callbacks may invoked before the driver has finished binding to the device or after the driver has unbound from the device. This problem shows up with the sd and sr drivers, and can cause disk or CD/DVD drives to become unusable as a result. The fix is simple. The drivers store a pointer to the scsi_disk or scsi_cd structure as their private device data when probing is finished, so we simply have to be sure to clear the private data during removal and test it during runtime suspend/resume. This fixes . Signed-off-by: Alan Stern Reported-by: Paul Menzel Reported-by: Erich Schubert Reported-by: Alexandre Rossi Tested-by: Paul Menzel Tested-by: Erich Schubert Signed-off-by: James Bottomley [bwh: Backported to 3.2: drop changes to sr as it doesn't support runtime PM] Signed-off-by: Ben Hutchings Signed-off-by: Willy Tarreau --- drivers/scsi/sd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c index 9202fc8..88de52c 100644 --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2311,8 +2311,8 @@ static int sd_suspend(struct device *dev, pm_message_t mesg) struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); int ret = 0; - if (!sdkp) - return 0; /* this can happen */ + if (!sdkp) /* E.g.: runtime suspend following sd_remove() */ + return 0; if (sdkp->WCE) { sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n"); @@ -2336,6 +2336,9 @@ static int sd_resume(struct device *dev) struct scsi_disk *sdkp = scsi_disk_get_from_dev(dev); int ret = 0; + if (!sdkp) /* E.g.: runtime resume at the start of sd_probe() */ + return 0; + if (!sdkp->device->manage_start_stop) goto done; -- 1.7.12.2.21.g234cd45.dirty