On Thu, Feb 04, 2021 at 01:53:59PM +0100, Dmitry Vyukov wrote: > Humm... I was thinking of perf_event_open(pid == 0). > It does not make sense to send SIGTRAP in a remote process, because it > does not necessarily cooperate with us. > > But is there any problem with clone w/o CLONE_THREAD? Assuming the > current process has setup the signal handler, the child will have the > same handler and the same code/address space. So delivery of SIGTRAP > should work the same way in the child.
Nothing should be doing CLONE_VM without CLONE_THREAD. Yes, it's possible, but if you do so, you get to keep the pieces IMO. Current libc either does a full clone (fork) or pthread_create, pthread_create does CLONE_THREAD.