On Thu, Feb 04, 2021 at 01:09:13PM +0100, Peter Zijlstra wrote: > And I need to dig into that fcntl() crud again, see if that's capable of > doing a SIGTRAP and if it's possible to target that to the task raising > it, instead of doing a process wide signal delivery.
Hmm, so it might be possible to extend SETOWN_EX to allow {F_OWNER_TID,0} to mean any current thread. And I think SETSIG can be used to set SIGTRAP, although I don't see it setting the fields you wanted, not entirely sure that's fixable.