diff --git a/sys/vm/vm_page.c b/sys/vm/vm_page.c
index 6d55892..6c85664 100644
--- a/sys/vm/vm_page.c
+++ b/sys/vm/vm_page.c
@@ -474,10 +474,10 @@ vm_page_startup(vm_offset_t vaddr)
 }
 
 void
-vm_page_flag_set(vm_page_t m, unsigned short bits)
+vm_page_flag_set(vm_page_t m, uint16_t bits)
 {
+	uint32_t *addr;
 
-	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
 	/*
 	 * The PG_WRITEABLE flag can only be set if the page is managed and
 	 * VPO_BUSY.  Currently, this flag is only set by pmap_enter().
@@ -485,21 +485,25 @@ vm_page_flag_set(vm_page_t m, unsigned short bits)
 	KASSERT((bits & PG_WRITEABLE) == 0 ||
 	    (m->oflags & (VPO_UNMANAGED | VPO_BUSY)) == VPO_BUSY,
 	    ("PG_WRITEABLE and !VPO_BUSY"));
-	m->flags |= bits;
+	addr = (void *)&m->flags;
+	MPASS(((uintptr_t)addr & 0x3) == 0);
+	atomic_set_32(addr, bits);
 } 
 
 void
-vm_page_flag_clear(vm_page_t m, unsigned short bits)
+vm_page_flag_clear(vm_page_t m, uint16_t bits)
 {
+	uint32_t *addr;
 
-	mtx_assert(&vm_page_queue_mtx, MA_OWNED);
 	/*
 	 * The PG_REFERENCED flag can only be cleared if the object
 	 * containing the page is locked.
 	 */
 	KASSERT((bits & PG_REFERENCED) == 0 || VM_OBJECT_LOCKED(m->object),
 	    ("PG_REFERENCED and !VM_OBJECT_LOCKED"));
-	m->flags &= ~bits;
+	addr = (void *)&m->flags;
+	MPASS(((uintptr_t)addr & 0x3) == 0);
+	atomic_clear_32(addr, bits);
 }
 
 void
diff --git a/sys/vm/vm_page.h b/sys/vm/vm_page.h
index 1dda1e2..8cff926 100644
--- a/sys/vm/vm_page.h
+++ b/sys/vm/vm_page.h
@@ -114,6 +114,12 @@
 TAILQ_HEAD(pglist, vm_page);
 
 struct vm_page {
+	uint16_t flags;			/* see below */
+	uint8_t	queue;			/* page queue index (P,Q) */
+	int8_t segind;
+	uint8_t	order;			/* index of the buddy queue */
+	uint8_t pool;
+	u_short cow;			/* page cow mapping count (P) */
 	TAILQ_ENTRY(vm_page) pageq;	/* queue info for FIFO queue or free list (Q) */
 	TAILQ_ENTRY(vm_page) listq;	/* pages in same object (O) 	*/
 	struct vm_page *left;		/* splay tree link (O)		*/
@@ -123,12 +129,6 @@ struct vm_page {
 	vm_pindex_t pindex;		/* offset into object (O,P) */
 	vm_paddr_t phys_addr;		/* physical address of page */
 	struct md_page md;		/* machine dependant stuff */
-	uint8_t	queue;			/* page queue index (P,Q) */
-	int8_t segind;
-	u_short	flags;			/* see below */
-	uint8_t	order;			/* index of the buddy queue */
-	uint8_t pool;
-	u_short cow;			/* page cow mapping count (P) */
 	u_int wire_count;		/* wired down maps refs (P) */
 	short hold_count;		/* page hold count (P) */
 	u_short oflags;			/* page flags (O) */
@@ -341,8 +341,8 @@ extern struct vpglocks vm_page_queue_lock;
 #define	VM_ALLOC_COUNT_SHIFT	16
 #define	VM_ALLOC_COUNT(count)	((count) << VM_ALLOC_COUNT_SHIFT)
 
-void vm_page_flag_set(vm_page_t m, unsigned short bits);
-void vm_page_flag_clear(vm_page_t m, unsigned short bits);
+void vm_page_flag_set(vm_page_t m, uint16_t bits);
+void vm_page_flag_clear(vm_page_t m, uint16_t bits);
 void vm_page_busy(vm_page_t m);
 void vm_page_flash(vm_page_t m);
 void vm_page_io_start(vm_page_t m);