By using the 32-bit Linux version of Sun's Java Development Kit 1.6

on FreeBSD (amd64), invocations of "javac" (or "java") eventually
end with the output of "Killed" and exit code 137.

This is caused by:
1. After calling exec() in multithreaded linux program threads are not
   destroyed and continue running. They get killed after program being
   executed finishes.

2. linux_exit_group doesn't return correct exit code when called not
   from group leader. Which happens regularly using sun jvm.

The submitters fix this in a similar way to how NetBSD handles this.

I took the PRs away from dchagin, who seems to be out of touch of
this since a while (no response from him).

The patches committed here are from [2], with some little modifications
from me to the style.

PR:		141439 [1], 144194 [2]
Submitted by:	Stefan Schmidt <stefan.schmidt@stadtbuch.de>, gk
Reviewed by:	rdivacky (in april 2010)
MFC after:	5 days

1 files changed, 10 insertions, 21 deletions

diff --git a/sys/compat/linux/linux_misc.c b/sys/compat/linux/linux_misc.c
index d2cf6b6..c50bf1c 100644
--- a/sys/compat/linux/linux_misc.c
+++ b/sys/compat/linux/linux_misc.c
@@ -1695,34 +1695,23 @@ linux_setdomainname(struct thread *td, struct linux_setdomainname_args *args)
 int
 linux_exit_group(struct thread *td, struct linux_exit_group_args *args)
 {
-	struct linux_emuldata *em, *td_em, *tmp_em;
-	struct proc *sp;
+	struct linux_emuldata *em;
 
 #ifdef DEBUG
 	if (ldebug(exit_group))
 		printf(ARGS(exit_group, "%i"), args->error_code);
 #endif
 
-	if (linux_use26(td)) {
-		td_em = em_find(td->td_proc, EMUL_DONTLOCK);
-
-		KASSERT(td_em != NULL, ("exit_group: emuldata not found.\n"));
-
-		EMUL_SHARED_RLOCK(&emul_shared_lock);
-		LIST_FOREACH_SAFE(em, &td_em->shared->threads, threads, tmp_em) {
-			if (em->pid == td_em->pid)
-				continue;
-
-			sp = pfind(em->pid);
-			psignal(sp, SIGKILL);
-			PROC_UNLOCK(sp);
-#ifdef DEBUG
-			printf(LMSG("linux_sys_exit_group: kill PID %d\n"), em->pid);
-#endif
-		}
-
-		EMUL_SHARED_RUNLOCK(&emul_shared_lock);
+	em = em_find(td->td_proc, EMUL_DONTLOCK);
+	if (em->shared->refs > 1) {
+		EMUL_SHARED_WLOCK(&emul_shared_lock);
+		em->shared->flags |= EMUL_SHARED_HASXSTAT;
+		em->shared->xstat = W_EXITCODE(args->error_code, 0);
+		EMUL_SHARED_WUNLOCK(&emul_shared_lock);
+		if (linux_use26(td))
+			linux_kill_threads(td, SIGKILL);
 	}
+
 	/*
 	 * XXX: we should send a signal to the parent if
 	 * SIGNAL_EXIT_GROUP is set. We ignore that (temporarily?)