6.6-stable review patch. If anyone has any objections, please let me know.
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From: Cong Zhang cong.zhang@oss.qualcomm.com
[ Upstream commit 10845a105bbcb030647a729f1716c2309da71d33 ]
If an hctx has no software ctx mapped, blk_mq_map_swqueue() never allocates tags and leaves hctx->tags NULL. The CPU hotplug offline notifier can still run for that hctx, return early since hctx cannot hold any requests.
Signed-off-by: Cong Zhang cong.zhang@oss.qualcomm.com Fixes: bf0beec0607d ("blk-mq: drain I/O when all CPUs in a hctx are offline") Reviewed-by: Ming Lei ming.lei@redhat.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- block/blk-mq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/block/blk-mq.c b/block/blk-mq.c index a3cd5079557b..427a36237da3 100644 --- a/block/blk-mq.c +++ b/block/blk-mq.c @@ -3578,7 +3578,7 @@ static int blk_mq_hctx_notify_offline(unsigned int cpu, struct hlist_node *node) struct blk_mq_hw_ctx, cpuhp_online); int ret = 0;
- if (blk_mq_hctx_has_online_cpu(hctx, cpu)) + if (!hctx->nr_ctx || blk_mq_hctx_has_online_cpu(hctx, cpu)) return 0;
/*