Eric, et al, sorry for delay, I didn't read emails several days. On 06/10, Eric W. Biederman wrote: > > v2: Don't remove the now unnecessary code in prepare_signal. No, that code is still needed. Otherwise any fatal signal will be turned into SIGKILL. > --- a/fs/coredump.c > +++ b/fs/coredump.c > @@ -519,7 +519,7 @@ static bool dump_interrupted(void) > * but then we need to teach dump_write() to restart and clear > * TIF_SIGPENDING. > */ > - return signal_pending(current); > + return fatal_signal_pending(current) || freezing(current); > } Well yes, this is what the comment says. But note that there is another reason why dump_interrupted() returns true if signal_pending(), it assumes thagt __dump_emit()->__kernel_write() may fail anyway if signal_pending() is true. Say, pipe_write(), or iirc nfs, perhaps something else... That is why zap_threads() clears TIF_SIGPENDING. Perhaps it should clear TIF_NOTIFY_SIGNAL as well and we should change io-uring to not abuse the dumping threads? Or perhaps we should change __dump_emit() to clear signal_pending() and restart __kernel_write() if it fails or returns a short write. Otherwise the change above doesn't look like a full fix to me. Oleg.
