@@ -3120,8 +3120,8 @@ static int sd_suspend_common(struct device *dev, bool ignore_stop_errors)
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 && sdkp->media_present) {
sd_printk(KERN_NOTICE, sdkp, "Synchronizing SCSI cache\n");
@@ -3162,6 +3162,9 @@ 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;
@@ -144,6 +144,9 @@ static int sr_runtime_suspend(struct device *dev)
{
struct scsi_cd *cd = dev_get_drvdata(dev);
+ if (!cd) /* E.g.: runtime suspend following sr_remove() */
+ return 0;
+
if (cd->media_present)
return -EBUSY;
else
@@ -988,6 +991,7 @@ static int sr_remove(struct device *dev)
scsi_autopm_get_device(cd->device);
del_gendisk(cd->disk);
+ dev_set_drvdata(dev, NULL);
mutex_lock(&sr_ref_mutex);
kref_put(&cd->kref, sr_kref_release);
This is a note to let you know that I have just added a patch titled SCSI: fix crashes in sd and sr runtime PM to the linux-3.16.y-queue branch of the 3.16.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.16.y-queue This patch is scheduled to be released in version 3.16.7-ckt25. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.16.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Luis ---8<------------------------------------------------------------ From 446c7d0ac2244591db162c9c0e1890599cf072df Mon Sep 17 00:00:00 2001 From: Alan Stern <stern@rowland.harvard.edu> Date: Wed, 20 Jan 2016 11:26:01 -0500 Subject: SCSI: fix crashes in sd and sr runtime PM 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 <https://bugs.debian.org/801925>. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Reported-by: Paul Menzel <paul.menzel@giantmonkey.de> Reported-by: Erich Schubert <erich@debian.org> Reported-by: Alexandre Rossi <alexandre.rossi@gmail.com> Tested-by: Paul Menzel <paul.menzel@giantmonkey.de> Tested-by: Erich Schubert <erich@debian.org> Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com> Signed-off-by: Luis Henriques <luis.henriques@canonical.com> --- drivers/scsi/sd.c | 7 +++++-- drivers/scsi/sr.c | 4 ++++ 2 files changed, 9 insertions(+), 2 deletions(-)