Revert "SCSI: Fix NULL pointer dereference in runtime PM (really closes: #801925)"

This reverts commit 41c5be2e73.  The
patch it adds is already in 4.4 and this will allow for a clean merge
from master.

debian/changelog

@@ -1,9 +1,3 @@
-linux (4.3.5-2) UNRELEASED; urgency=medium
-
-  * SCSI: Fix NULL pointer dereference in runtime PM (really closes: #801925)
-
- -- Ben Hutchings <ben@decadent.org.uk>  Tue, 09 Feb 2016 20:48:32 +0000
-
 linux (4.3.5-1) unstable; urgency=medium
 
   * New upstream stable update:

debian/patches/bugfix/all/scsi-fix-null-pointer-dereference-in-runtime-pm.patch

@@ -1,82 +0,0 @@
-From: Ken Xue <ken.xue@amd.com>
-Date: Tue, 1 Dec 2015 14:45:46 +0800
-Subject: SCSI: Fix NULL pointer dereference in runtime PM
-Origin: https://git.kernel.org/linus/4fd41a8552afc01054d9d9fc7f1a63c324867d27
-Bug: https://bugzilla.kernel.org/show_bug.cgi?id=101371
-Bug-Debian: https://bugs.debian.org/801925
-
-The routines in scsi_pm.c assume that if a runtime-PM callback is
-invoked for a SCSI device, it can only mean that the device's driver
-has asked the block layer to handle the runtime power management (by
-calling blk_pm_runtime_init(), which among other things sets q->dev).
-
-However, this assumption turns out to be wrong for things like the ses
-driver.  Normally ses devices are not allowed to do runtime PM, but
-userspace can override this setting.  If this happens, the kernel gets
-a NULL pointer dereference when blk_post_runtime_resume() tries to use
-the uninitialized q->dev pointer.
-
-This patch fixes the problem by checking q->dev in block layer before
-handle runtime PM. Since ses doesn't define any PM callbacks and call
-blk_pm_runtime_init(), the crash won't occur.
-
-This fixes Bugzilla #101371.
-https://bugzilla.kernel.org/show_bug.cgi?id=101371
-
-More discussion can be found from below link.
-http://marc.info/?l=linux-scsi&m=144163730531875&w=2
-
-Signed-off-by: Ken Xue <Ken.Xue@amd.com>
-Acked-by: Alan Stern <stern@rowland.harvard.edu>
-Cc: Xiangliang Yu <Xiangliang.Yu@amd.com>
-Cc: James E.J. Bottomley <JBottomley@odin.com>
-Cc: Jens Axboe <axboe@kernel.dk>
-Cc: Michael Terry <Michael.terry@canonical.com>
-Cc: stable@vger.kernel.org
-Signed-off-by: Jens Axboe <axboe@fb.com>
----
- block/blk-core.c | 12 ++++++++++++
- 1 file changed, 12 insertions(+)
-
---- a/block/blk-core.c
-+++ b/block/blk-core.c
-@@ -3280,6 +3280,9 @@ int blk_pre_runtime_suspend(struct reque
- {
- 	int ret = 0;
- 
-+	if (!q->dev)
-+		return ret;
-+
- 	spin_lock_irq(q->queue_lock);
- 	if (q->nr_pending) {
- 		ret = -EBUSY;
-@@ -3307,6 +3310,9 @@ EXPORT_SYMBOL(blk_pre_runtime_suspend);
-  */
- void blk_post_runtime_suspend(struct request_queue *q, int err)
- {
-+	if (!q->dev)
-+		return;
-+
- 	spin_lock_irq(q->queue_lock);
- 	if (!err) {
- 		q->rpm_status = RPM_SUSPENDED;
-@@ -3331,6 +3337,9 @@ EXPORT_SYMBOL(blk_post_runtime_suspend);
-  */
- void blk_pre_runtime_resume(struct request_queue *q)
- {
-+	if (!q->dev)
-+		return;
-+
- 	spin_lock_irq(q->queue_lock);
- 	q->rpm_status = RPM_RESUMING;
- 	spin_unlock_irq(q->queue_lock);
-@@ -3353,6 +3362,9 @@ EXPORT_SYMBOL(blk_pre_runtime_resume);
-  */
- void blk_post_runtime_resume(struct request_queue *q, int err)
- {
-+	if (!q->dev)
-+		return;
-+
- 	spin_lock_irq(q->queue_lock);
- 	if (!err) {
- 		q->rpm_status = RPM_ACTIVE;

debian/patches/series

@@ -142,4 +142,3 @@ bugfix/all/rt2x00-fix-monitor-mode-regression.patch
 bugfix/all/pipe-limit-the-per-user-amount-of-pages-allocated-in.patch
 bugfix/all/fix-abi-changes-for-cve-2013-4312-fix.patch
 features/sparc/hwrng-n2-attach-on-t5-m5-t7-m7-sparc-cpus.patch
-bugfix/all/scsi-fix-null-pointer-dereference-in-runtime-pm.patch