Re: [PATCH] block, bfq: switch 'bfqg->ref' to use atomic refcount apis

[Jens Axboe]

On Tue, 03 Jan 2023 16:47:55 +0800, Yu Kuai wrote:
> The updating of 'bfqg->ref' should be protected by 'bfqd->lock', however,
> during code review, we found that bfq_pd_free() update 'bfqg->ref'
> without holding the lock, which is problematic:
> 
> 1) bfq_pd_free() triggered by removing cgroup is called asynchronously;
> 2) bfqq will grab bfqg reference, and exit bfqq will drop the reference,
> which can concurrent with 1).
> 
> [...]

Applied, thanks!

[1/1] block, bfq: switch 'bfqg->ref' to use atomic refcount apis
      commit: 216f764716f34fe68cedc7296ae2043a7727e640

Best regards,
-- 
Jens Axboe