This is a note to let you know that I've just added the patch titled
blk-mq: Fix tagset reinit in the presence of cpu hot-unplug
to the 4.9-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:
blk-mq-fix-tagset-reinit-in-the-presence-of-cpu-hot-unplug.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Mon Dec 18 14:12:34 CET 2017
From: Sagi Grimberg <sagi@xxxxxxxxxxx>
Date: Mon, 13 Mar 2017 16:10:11 +0200
Subject: blk-mq: Fix tagset reinit in the presence of cpu hot-unplug
From: Sagi Grimberg <sagi@xxxxxxxxxxx>
[ Upstream commit 0067d4b020ea07a58540acb2c5fcd3364bf326e0 ]
In case cpu was unplugged, we need to make sure not to assume
that the tags for that cpu are still allocated. so check
for null tags when reinitializing a tagset.
Reported-by: Yi Zhang <yizhan@xxxxxxxxxx>
Signed-off-by: Sagi Grimberg <sagi@xxxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
block/blk-mq-tag.c | 3 +++
1 file changed, 3 insertions(+)
--- a/block/blk-mq-tag.c
+++ b/block/blk-mq-tag.c
@@ -311,6 +311,9 @@ int blk_mq_reinit_tagset(struct blk_mq_t
for (i = 0; i < set->nr_hw_queues; i++) {
struct blk_mq_tags *tags = set->tags[i];
+ if (!tags)
+ continue;
+
for (j = 0; j < tags->nr_tags; j++) {
if (!tags->rqs[j])
continue;
Patches currently in stable-queue which might be from sagi@xxxxxxxxxxx are
queue-4.9/blk-mq-fix-tagset-reinit-in-the-presence-of-cpu-hot-unplug.patch
queue-4.9/nvmet-confirm-sq-percpu-has-scheduled-and-switched-to-atomic.patch
queue-4.9/nvme-use-kref_get_unless_zero-in-nvme_find_get_ns.patch
queue-4.9/nvme-loop-fix-a-possible-use-after-free-when-destroying-the-admin-queue.patch
queue-4.9/nvmet-rdma-fix-a-possible-uninitialized-variable-dereference.patch