This is a note to let you know that I've just added the patch titled
block: disable runtime-pm for blk-mq
to the 4.12-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
block-disable-runtime-pm-for-blk-mq.patch
and it can be found in the queue-4.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 765e40b675a9566459ddcb8358ad16f3b8344bbe Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@xxxxxx>
Date: Fri, 21 Jul 2017 13:46:10 +0200
Subject: block: disable runtime-pm for blk-mq
From: Christoph Hellwig <hch@xxxxxx>
commit 765e40b675a9566459ddcb8358ad16f3b8344bbe upstream.
The blk-mq code lacks support for looking at the rpm_status field, tracking
active requests and the RQF_PM flag.
Due to the default switch to blk-mq for scsi people start to run into
suspend / resume issue due to this fact, so make sure we disable the runtime
PM functionality until it is properly implemented.
Signed-off-by: Christoph Hellwig <hch@xxxxxx>
Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Cc: Oleksandr Natalenko <oleksandr@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
block/blk-core.c | 4 ++++
1 file changed, 4 insertions(+)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -3307,6 +3307,10 @@ EXPORT_SYMBOL(blk_finish_plug);
*/
void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
{
+ /* not support for RQF_PM and ->rpm_status in blk-mq yet */
+ if (q->mq_ops)
+ return;
+
q->dev = dev;
q->rpm_status = RPM_ACTIVE;
pm_runtime_set_autosuspend_delay(q->dev, -1);
Patches currently in stable-queue which might be from hch@xxxxxx are
queue-4.12/block-disable-runtime-pm-for-blk-mq.patch
queue-4.12/blk-mq-create-hctx-for-each-present-cpu.patch
queue-4.12/blk-mq-include-all-present-cpus-in-the-default-queue-mapping.patch