Don't drop the big lock at the end of exit1(), but move it into the middle of

sched_exit().  This means that cpu_exit() and whatever it does (for instance
calling free(), as well as the deadproc p_hash handling are now locked as well.
This may have been one of the causes of the reaper panics, especially with
rthread patches... which were terminating a lot of threads very quickly onto
the deadproc p_hash list.
ok kurt kettenis miod

2 files changed, 4 insertions, 8 deletions

diff --git a/sys/kern/kern_exit.c b/sys/kern/kern_exit.c
index 23c11c5283a..b8336c38499 100644
--- a/sys/kern/kern_exit.c
+++ b/sys/kern/kern_exit.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_exit.c,v 1.85 2009/06/24 13:03:20 kurt Exp $	*/
+/*	$OpenBSD: kern_exit.c,v 1.86 2009/10/05 17:43:07 deraadt Exp $	*/
 /*	$NetBSD: kern_exit.c,v 1.39 1996/04/22 01:38:25 christos Exp $	*/
 
 /*
@@ -319,9 +319,6 @@ exit1(struct proc *p, int rv, int flags)
 	if (p->p_emul->e_proc_exit)
 		(*p->p_emul->e_proc_exit)(p);
 
-	/* This process no longer needs to hold the kernel lock. */
-	KERNEL_PROC_UNLOCK(p);
-
 	/*
 	 * Finally, call machine-dependent code to switch to a new
 	 * context (possibly the idle context).  Once we are no longer
diff --git a/sys/kern/kern_sched.c b/sys/kern/kern_sched.c
index 08694052d08..15d57cf037c 100644
--- a/sys/kern/kern_sched.c
+++ b/sys/kern/kern_sched.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kern_sched.c,v 1.13 2009/04/22 08:35:54 art Exp $	*/
+/*	$OpenBSD: kern_sched.c,v 1.14 2009/10/05 17:43:08 deraadt Exp $	*/
 /*
  * Copyright (c) 2007, 2008 Artur Grabowski <art@openbsd.org>
  *
@@ -180,9 +180,8 @@ sched_exit(struct proc *p)
 
 	LIST_INSERT_HEAD(&spc->spc_deadproc, p, p_hash);
 
-#ifdef MULTIPROCESSOR
-	KASSERT(__mp_lock_held(&kernel_lock) == 0);
-#endif
+	/* This process no longer needs to hold the kernel lock. */
+	KERNEL_PROC_UNLOCK(p);
 
 	SCHED_LOCK(s);
 	idle = spc->spc_idleproc;