On 10/6/20 9:16 PM, Muchun Song wrote:

We should make sure that async workqueue is canceled on exit, but on
some corner case, we found that the async workqueue is not canceled
on exit in the linux-5.4. So we started an in-depth investigation.
Fortunately, we finally found the problem. The commit:

  1c4404efcf2c ("io_uring: make sure async workqueue is canceled on exit")

did not completely solve this problem. This patch series to solve this
problem completely. And there's no upstream variant of this commit, so
this patch series is just fix the linux-5.4.y stable branch.

Thanks, I'll review/test these and pass them on if good.

-- 
Jens Axboe