diff --git a/kernel-src/mm/pmm.c b/kernel-src/mm/pmm.c
index 93125770..5570b442 100644
--- a/kernel-src/mm/pmm.c
+++ b/kernel-src/mm/pmm.c
@@ -133,6 +133,7 @@ void pmm_release(void *addr) {
 
 	uintmax_t newrefcount = __atomic_sub_fetch(&page->refcount, 1, __ATOMIC_SEQ_CST);
 	if (newrefcount == 0) {
+		__assert((page->flags & PAGE_FLAGS_DIRTY) == 0);
 		MUTEX_ACQUIRE(&freelistmutex, false);
 		insertinfreelist(page);
 		if (page->backing == NULL)
diff --git a/kernel-src/mm/vmm.c b/kernel-src/mm/vmm.c
index a6057710..9341e475 100644
--- a/kernel-src/mm/vmm.c
+++ b/kernel-src/mm/vmm.c
@@ -223,15 +223,20 @@ static void destroyrange(vmmrange_t *range, uintmax_t _offset, size_t size, int
 			if (range->vnode->type == V_TYPE_CHDEV) {
 				// character device mapping
 				__assert(VOP_MUNMAP(range->vnode, vaddr, range->offset + offset, mmuflagstovnodeflags(range->mmuflags) | (range->flags & VMM_FLAGS_SHARED ? V_FFLAGS_SHARED : 0), cred) == 0);
-			} else if (arch_mmu_iswritable(_cpu()->vmmctx->pagetable, vaddr) == false || arch_mmu_isdirty(_cpu()->vmmctx->pagetable, vaddr) == false) {
+			} else if (arch_mmu_iswritable(_cpu()->vmmctx->pagetable, vaddr) && arch_mmu_isdirty(_cpu()->vmmctx->pagetable, vaddr)) {
 				// dirty page cache mapping
+				arch_mmu_unmap(_cpu()->vmmctx->pagetable, vaddr);
 				vmmcache_makedirty(pmm_getpage(physical));
 				pmm_release(physical);
+			} else {
+				// non dirty page mapping
+				arch_mmu_unmap(_cpu()->vmmctx->pagetable, vaddr);
+				pmm_release(physical);
 			}
 		} else {
 			// anonymous or private non character device mapping
-			pmm_release(physical);
 			arch_mmu_unmap(_cpu()->vmmctx->pagetable, vaddr);
+			pmm_release(physical);
 		}
 	}