Re: [PATCH v2] block/blk-cgroup-rwstat: use data_race() for online test

From: Jens Axboe

Date: Mon Aug 03 2026 - 22:22:26 EST



On Mon, 03 Aug 2026 21:34:00 +0800, Tao Cui wrote:
> blkg_rwstat_recursive_sum() reads pos_blkg->online without the queue
> lock that its doc comment requires, since blkcg_print_blkgs() stopped
> holding it in 56cc24f59c14. Concurrent blkg_create/destroy flips
> ->online, tripping KCSAN. The race is harmless (RCU-protected, stale
> online only causes minor stat noise). Use data_race() to annotate
> the intentional lockless read.
>
> [...]

Applied, thanks!

[1/1] block/blk-cgroup-rwstat: use data_race() for online test
(no commit info)

Best regards,
--
Jens Axboe