On 10/19/20 9:39 AM, Pavel Begunkov wrote: > io_link_timeout_fn() removes REQ_F_LINK_TIMEOUT from the link head's > flags, it's not atomic and may race with what the head is doing. > > If io_link_timeout_fn() doesn't clear the flag, as forced by this patch, > then it may happen that for "req -> link_timeout1 -> link_timeout2", > __io_kill_linked_timeout() would find link_timeout2 and try to cancel > it, so miscounting references. Teach it to ignore such double timeouts > by marking the active one with a new flag in io_prep_linked_timeout(). Applied, thanks. -- Jens Axboe
