Index: sys/vm/vm_reserv.c
===================================================================
--- sys/vm/vm_reserv.c
+++ sys/vm/vm_reserv.c
@@ -317,6 +317,9 @@
 		seg = &vm_phys_segs[segind];
 		paddr = roundup2(seg->start, VM_LEVEL_0_SIZE);
 		while (paddr + VM_LEVEL_0_SIZE <= seg->end) {
+			/* Check paddr to not overflow. */
+			if (paddr + VM_LEVEL_0_SIZE < paddr)
+				break;
 			rv = &vm_reserv_array[paddr >> VM_LEVEL_0_SHIFT];
 			fullpop += rv->popcnt == VM_LEVEL_0_NPAGES;
 			paddr += VM_LEVEL_0_SIZE;
@@ -1056,6 +1059,9 @@
 		seg = &vm_phys_segs[segind];
 		paddr = roundup2(seg->start, VM_LEVEL_0_SIZE);
 		while (paddr + VM_LEVEL_0_SIZE <= seg->end) {
+			/* Check paddr to not overflow. */
+			if (paddr + VM_LEVEL_0_SIZE < paddr)
+				break;
 			rv = &vm_reserv_array[paddr >> VM_LEVEL_0_SHIFT];
 			rv->pages = PHYS_TO_VM_PAGE(paddr);
 			rv->domain = seg->domain;