Signals sent specifically to a particular thread must

be delivered to that thread, regardless of whether it
has it masked or not.

Previously, if the targeted thread had the signal masked,
it would be put on the processes' siglist. If
another thread has the signal umasked or unmasks it before
the target, then the thread it was intended for would never
receive it.

This patch attempts to solve the problem by requiring callers
of tdsignal() to say whether the signal is for the thread or
for the process. If it is for the process, then normal processing
occurs and any thread that has it unmasked can receive it.
But if it is destined for a specific thread, it is put on
that thread's pending list regardless of whether it is currently
masked or not.

The new behaviour still needs more work, though.  If the signal
is reposted for some reason it is always posted back to the
thread that handled it because the information regarding the
target of the signal has been lost by then.

Reviewed by:	jdp, jeff, bde (style)

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/kern/kern_kse.c b/sys/kern/kern_kse.c
index bc71b47..4ea5231 100644
--- a/sys/kern/kern_kse.c
+++ b/sys/kern/kern_kse.c
@@ -413,7 +413,7 @@ kse_thr_interrupt(struct thread *td, struct kse_thr_interrupt_args *uap)
 	if (sig > 0) {
 		td2->td_flags &= ~TDF_INTERRUPT;
 		mtx_unlock_spin(&sched_lock);
-		tdsignal(td2, sig);
+		tdsignal(td2, sig, SIGTARGET_P);
 	} else if (sig == 0) {
 		mtx_unlock_spin(&sched_lock);
 	} else {