Index: sys/amd64/amd64/pmap.c
===================================================================
--- sys/amd64/amd64/pmap.c
+++ sys/amd64/amd64/pmap.c
@@ -358,6 +358,13 @@
 #define	CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m)	\
 			CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, VM_PAGE_TO_PHYS(m))
 
+#define PV_LIST_LOCK_MATCHES(lockp, pa) ({				\
+			(PHYS_TO_PV_LIST_LOCK(pa) == (*lockp));		\
+})
+
+#define PV_LIST_LOCK_MATCHES_VM_PAGE(lockp, m)		\
+			PV_LIST_LOCK_MATCHES(lockp, VM_PAGE_TO_PHYS(m))
+
 #define	RELEASE_PV_LIST_LOCK(lockp)		do {	\
 	struct rwlock **_lockp = (lockp);		\
 							\
@@ -1149,7 +1156,7 @@
 static void	free_pv_chunk(struct pv_chunk *pc);
 static void	free_pv_chunk_batch(struct pv_chunklist *batch);
 static void	free_pv_entry(pmap_t pmap, pv_entry_t pv);
-static pv_entry_t get_pv_entry(pmap_t pmap, struct rwlock **lockp);
+static pv_entry_t get_pv_entry(pmap_t pmap, bool reclaim, struct rwlock **lockp);
 static int	popcnt_pc_map_pq(uint64_t *map);
 static vm_page_t reclaim_pv_chunk(pmap_t locked_pmap, struct rwlock **lockp);
 static void	reserve_pv_entries(pmap_t pmap, int needed,
@@ -4160,7 +4167,6 @@
 	static int active_reclaims = 0;
 
 	PMAP_LOCK_ASSERT(locked_pmap, MA_OWNED);
-	KASSERT(lockp != NULL, ("reclaim_pv_chunk: lockp is NULL"));
 	pmap = NULL;
 	m_pc = NULL;
 	PG_G = PG_A = PG_M = PG_RW = 0;
@@ -4420,7 +4426,7 @@
  * The given PV list lock may be released.
  */
 static pv_entry_t
-get_pv_entry(pmap_t pmap, struct rwlock **lockp)
+get_pv_entry(pmap_t pmap, bool reclaim, struct rwlock **lockp)
 {
 	int bit, field;
 	pv_entry_t pv;
@@ -4457,7 +4463,7 @@
 	m = vm_page_alloc(NULL, 0, VM_ALLOC_NORMAL | VM_ALLOC_NOOBJ |
 	    VM_ALLOC_WIRED);
 	if (m == NULL) {
-		if (lockp == NULL) {
+		if (!reclaim) {
 			PV_STAT(pc_chunk_tryfail++);
 			return (NULL);
 		}
@@ -4747,8 +4753,9 @@
 	pv_entry_t pv;
 
 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
-	/* Pass NULL instead of the lock pointer to disable reclamation. */
-	if ((pv = get_pv_entry(pmap, NULL)) != NULL) {
+	if (!PV_LIST_LOCK_MATCHES_VM_PAGE(lockp, m))
+		RELEASE_PV_LIST_LOCK(lockp);
+	if ((pv = get_pv_entry(pmap, false, NULL)) != NULL) {
 		pv->pv_va = va;
 		CHANGE_PV_LIST_LOCK_TO_VM_PAGE(lockp, m);
 		TAILQ_INSERT_TAIL(&m->md.pv_list, pv, pv_next);
@@ -4772,12 +4779,13 @@
 	vm_paddr_t pa;
 
 	PMAP_LOCK_ASSERT(pmap, MA_OWNED);
-	/* Pass NULL instead of the lock pointer to disable reclamation. */
-	if ((pv = get_pv_entry(pmap, (flags & PMAP_ENTER_NORECLAIM) != 0 ?
-	    NULL : lockp)) == NULL)
+	pa = pde & PG_PS_FRAME;
+	if (!PV_LIST_LOCK_MATCHES(lockp, pa))
+		RELEASE_PV_LIST_LOCK(lockp);
+	pv = get_pv_entry(pmap, !(flags & PMAP_ENTER_NORECLAIM), lockp);
+	if (pv == NULL)
 		return (false);
 	pv->pv_va = va;
-	pa = pde & PG_PS_FRAME;
 	CHANGE_PV_LIST_LOCK_TO_PHYS(lockp, pa);
 	pvh = pa_to_pvh(pa);
 	TAILQ_INSERT_TAIL(&pvh->pv_list, pv, pv_next);
@@ -5978,7 +5986,9 @@
 	 */
 	if ((newpte & PG_MANAGED) != 0) {
 		if (pv == NULL) {
-			pv = get_pv_entry(pmap, &lock);
+			if (!PV_LIST_LOCK_MATCHES_VM_PAGE(&lock, m))
+				RELEASE_PV_LIST_LOCK(&lock);
+			pv = get_pv_entry(pmap, true, &lock);
 			pv->pv_va = va;
 		}
 		CHANGE_PV_LIST_LOCK_TO_PHYS(&lock, pa);
@@ -6171,6 +6181,7 @@
 		 * Abort this mapping if its PV entry could not be created.
 		 */
 		if (!pmap_pv_insert_pde(pmap, va, newpde, flags, lockp)) {
+			RELEASE_PV_LIST_LOCK(lockp);
 			SLIST_INIT(&free);
 			if (pmap_unwire_ptp(pmap, va, pdpg, &free)) {
 				/*
@@ -6350,6 +6361,7 @@
 	 */
 	if ((m->oflags & VPO_UNMANAGED) == 0 &&
 	    !pmap_try_insert_pv_entry(pmap, va, m, lockp)) {
+		RELEASE_PV_LIST_LOCK(lockp);
 		if (mpte != NULL) {
 			SLIST_INIT(&free);
 			if (pmap_unwire_ptp(pmap, va, mpte, &free)) {