Subject: [PATCH v1 1/2] block: bypass blk_set_runtime_active for uninitialized q->dev

From: Stanley Chu <[email-masked]>
Date: Wed, 11 Sep 2019 14:32:41 +0800

Some devices may skip blk_pm_runtime_init() and have null pointer
in its request_queue->dev. For example, SCSI devices of UFS Well-Known
LUNs.

Currently the null pointer is checked by the user of
blk_set_runtime_active(), i.e., scsi_dev_type_resume(). It is better to
check it by blk_set_runtime_active() itself instead of by its users.

Signed-off-by: Stanley Chu <[email-masked]>
---
 block/blk-pm.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/block/blk-pm.c b/block/blk-pm.c
index 0a028c189897..56ed94f7a2a3 100644
--- a/block/blk-pm.c
+++ b/block/blk-pm.c
@@ -207,6 +207,9 @@ EXPORT_SYMBOL(blk_post_runtime_resume);
  */
 void blk_set_runtime_active(struct request_queue *q)
 {
+	if (!q->dev)
+		return;
+
 	spin_lock_irq(&q->queue_lock);
 	q->rpm_status = RPM_ACTIVE;
 	pm_runtime_mark_last_busy(q->dev);
-- 
2.18.0

_______________________________________________
linux-arm-kernel mailing list
[email-masked]
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel