From 0e384220967e53780efb44fa673fb2e2f6c88d19 Mon Sep 17 00:00:00 2001
From: Konstantin Belousov <kib@FreeBSD.org>
Date: Tue, 24 May 2016 19:20:30 +0000
Subject: [PATCH] In vm_page_cache(), only drop the vnode after radix insert
 failure for empty page cache when the object type if OBJT_VNODE.

Reported and tested by:	pho
Reviewed by:	alc
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
---
 sys/vm/vm_page.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index de08bcedba1..7082eccd77a 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -3290,7 +3290,8 @@ vm_page_cache(vm_page_t m)
 	cache_was_empty = vm_radix_is_empty(&object->cache);
 	if (vm_radix_insert(&object->cache, m)) {
 		mtx_unlock(&vm_page_queue_free_mtx);
-		if (object->resident_page_count == 0)
+		if (object->type == OBJT_VNODE &&
+		    object->resident_page_count == 0)
 			vdrop(object->handle);
 		m->object = NULL;
 		vm_page_free(m);