git: 54747740ccc6 - stable/13 - sigtd(): prefer non-stopped thread as a target for signal queue

The branch stable/13 has been updated by kib:

URL: https://cgit.FreeBSD.org/src/commit/?id=54747740ccc6a717c54f23324639bedff5f64211

commit 54747740ccc6a717c54f23324639bedff5f64211
Author:     Konstantin Belousov <kib@FreeBSD.org>
AuthorDate: 2023-07-21 09:41:39 +0000
Commit:     Konstantin Belousov <kib@FreeBSD.org>
CommitDate: 2023-08-07 00:48:45 +0000

    sigtd(): prefer non-stopped thread as a target for signal queue
    
    (cherry picked from commit dfe172484d0e1de0bb32bcab8775eb83e15031c0)
---
 sys/kern/kern_sig.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/sys/kern/kern_sig.c b/sys/kern/kern_sig.c
index 77f63252454a..e002d7d0e5fa 100644
--- a/sys/kern/kern_sig.c
+++ b/sys/kern/kern_sig.c
@@ -2100,14 +2100,18 @@ sigtd(struct proc *p, int sig, bool fast_sigblock)
 	if (curproc == p && !SIGISMEMBER(curthread->td_sigmask, sig) &&
 	    (!fast_sigblock || curthread->td_sigblock_val == 0))
 		return (curthread);
+
+	/* Find a non-stopped thread that does not mask the signal. */
 	signal_td = NULL;
 	FOREACH_THREAD_IN_PROC(p, td) {
 		if (!SIGISMEMBER(td->td_sigmask, sig) && (!fast_sigblock ||
-		    td != curthread || td->td_sigblock_val == 0)) {
+		    td != curthread || td->td_sigblock_val == 0) &&
+		    (td->td_flags & TDF_BOUNDARY) == 0) {
 			signal_td = td;
 			break;
 		}
 	}
+	/* Select random (first) thread if no better match was found. */
 	if (signal_td == NULL)
 		signal_td = FIRST_THREAD_IN_PROC(p);
 	return (signal_td);