MFC r279362:

The VNASSERT in vflush() FORCECLOSE case is trying to panic early to
prevent errors from yanking devices out from under filesystems.  Only
care about special vnodes on devfs, special nodes on other kinds of
filesystems do not have special properties.

3 files changed, 3 insertions, 2 deletions

diff --git a/sys/fs/devfs/devfs_vnops.c b/sys/fs/devfs/devfs_vnops.c
index d3ab235..134f8b0 100644
--- a/sys/fs/devfs/devfs_vnops.c
+++ b/sys/fs/devfs/devfs_vnops.c
@@ -63,7 +63,6 @@
 #include <sys/vnode.h>
 
 static struct vop_vector devfs_vnodeops;
-static struct vop_vector devfs_specops;
 static struct fileops devfs_ops_f;
 
 #include <fs/devfs/devfs.h>
@@ -1737,7 +1736,7 @@ static struct vop_vector devfs_vnodeops = {
 	.vop_vptocnp =		devfs_vptocnp,
 };
 
-static struct vop_vector devfs_specops = {
+struct vop_vector devfs_specops = {
 	.vop_default =		&default_vnodeops,
 
 	.vop_access =		devfs_access,
diff --git a/sys/kern/vfs_subr.c b/sys/kern/vfs_subr.c
index a2690c6..8fb7734 100644
--- a/sys/kern/vfs_subr.c
+++ b/sys/kern/vfs_subr.c
@@ -2624,6 +2624,7 @@ loop:
 		 */
 		if (vp->v_usecount == 0 || (flags & FORCECLOSE)) {
 			VNASSERT(vp->v_usecount == 0 ||
+			    vp->v_op != &devfs_specops ||
 			    (vp->v_type != VCHR && vp->v_type != VBLK), vp,
 			    ("device VNODE %p is FORCECLOSED", vp));
 			vgonel(vp);
diff --git a/sys/sys/vnode.h b/sys/sys/vnode.h
index 20bd0a1..71b129e 100644
--- a/sys/sys/vnode.h
+++ b/sys/sys/vnode.h
@@ -819,6 +819,7 @@ void vnode_destroy_vobject(struct vnode *vp);
 extern struct vop_vector fifo_specops;
 extern struct vop_vector dead_vnodeops;
 extern struct vop_vector default_vnodeops;
+extern struct vop_vector devfs_specops;
 
 #define VOP_PANIC	((void*)(uintptr_t)vop_panic)
 #define VOP_NULL	((void*)(uintptr_t)vop_null)