Fix the recent panics/LORs/hangs created by my kqueue commit by:

- Introducing the possibility of using locks different than mutexes
for the knlist locking. In order to do this, we add three arguments to
knlist_init() to specify the functions to use to lock, unlock and
check if the lock is owned. If these arguments are NULL, we assume
mtx_lock, mtx_unlock and mtx_owned, respectively.

- Using the vnode lock for the knlist locking, when doing kqueue operations
on a vnode. This way, we don't have to lock the vnode while holding a
mutex, in filt_vfsread.

Reviewed by:	jmg
Approved by:	re (scottl), scottl (mentor override)
Pointyhat to:	ssouhlal
Will be happy:	everyone

1 files changed, 1 insertions, 1 deletions

diff --git a/sys/kern/kern_fork.c b/sys/kern/kern_fork.c
index 75214492a9ad..56ad939f480c 100644
--- a/sys/kern/kern_fork.c
+++ b/sys/kern/kern_fork.c
@@ -271,7 +271,7 @@ fork1(td, flags, pages, procp)
 #ifdef MAC
 	mac_init_proc(newproc);
 #endif
-	knlist_init(&newproc->p_klist, &newproc->p_mtx);
+	knlist_init(&newproc->p_klist, &newproc->p_mtx, NULL, NULL, NULL);
 
 	/* We have to lock the process tree while we look for a pid. */
 	sx_slock(&proctree_lock);