Re: [syzbot] possible deadlock in worker_thread

From: Bart Van Assche
Date: Sun Feb 13 2022 - 18:20:21 EST


On 2/12/22 09:14, Tetsuo Handa wrote:
How can reviewing all flush_workqueue(system_long_wq) calls help?

It is allowed to queue blocking actions on system_long_wq. flush_workqueue(system_long_wq) can make a lower layer (e.g. ib_srp) wait on a blocking action from a higher layer (e.g. the loop driver) and thereby cause a deadlock. Hence my proposal to review all flush_workqueue(system_long_wq) calls.

Thanks,

Bart.