Olivier Langlois <olivier@xxxxxxxxxxxxxx> writes: > 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. Did you mean? So the TIF_NOTIFY_SIGNAL does _not_ get set WHILE the core dump is written. Eric
