On Wed, 2021-06-09 at 13:33 -0700, Linus Torvalds wrote: > Now, the fact that we haven't cleared TIF_NOTIFY_SIGNAL for the first > signal is clearly the immediate cause of this, but at the same time I > really get the feeling that that coredump aborting code should always > had used fatal_signal_pending(). I need clarify what does happen with the io_uring situation. If somehow, TIF_NOTIFY_SIGNAL wasn't cleared, I would get all the time a 0 byte size core dump because do_coredump() does check if the dump is interrupted before writing a single byte. io_uring is quite a strange animal. AFAIK, the common pattern to use a wait_queue is to insert a task into it and then put that task to sleep until the waited event occur. io_uring place tasks into wait queues and then let the the task return to user space to do some other stuff (like core dumping). I would guess that it is the main reason for it using the task_work feature. So the TIF_NOTIFY_SIGNAL does get set WHILE the core dump is written. Greetings, Olivier
