---

yaml
---
r: 105288
b: refs/heads/master
c: cdfd432
h: refs/heads/master
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: e7c4b0bfd025f71cf7624b7c1be174f63caade33
+refs/heads/master: cdfd4325c0d878679bd6a3ba8285b71d9980e3c0

trunk/include/linux/mm.h

@@ -100,6 +100,7 @@ extern unsigned int kobjsize(const void *objp);
 #define VM_DONTEXPAND	0x00040000	/* Cannot expand with mremap() */
 #define VM_RESERVED	0x00080000	/* Count as reserved_vm like IO */
 #define VM_ACCOUNT	0x00100000	/* Is a VM accounted object */
+#define VM_NORESERVE	0x00200000	/* should the VM suppress accounting */
 #define VM_HUGETLB	0x00400000	/* Huge TLB Page VM */
 #define VM_NONLINEAR	0x00800000	/* Is non-linear (remap_file_pages) */
 #define VM_MAPPED_COPY	0x01000000	/* T if mapped copy of data (nommu mmap) */

trunk/mm/mmap.c

@@ -1110,6 +1110,9 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 	if (!may_expand_vm(mm, len >> PAGE_SHIFT))
 		return -ENOMEM;
 
+	if (flags & MAP_NORESERVE)
+		vm_flags |= VM_NORESERVE;
+
 	if (accountable && (!(flags & MAP_NORESERVE) ||
 			    sysctl_overcommit_memory == OVERCOMMIT_NEVER)) {
 		if (vm_flags & VM_SHARED) {

trunk/mm/mprotect.c

@@ -153,12 +153,10 @@ mprotect_fixup(struct vm_area_struct *vma, struct vm_area_struct **pprev,
 	 * If we make a private mapping writable we increase our commit;
 	 * but (without finer accounting) cannot reduce our commit if we
 	 * make it unwritable again.
-	 *
-	 * FIXME? We haven't defined a VM_NORESERVE flag, so mprotecting
-	 * a MAP_NORESERVE private mapping to writable will now reserve.
 	 */
 	if (newflags & VM_WRITE) {
-		if (!(oldflags & (VM_ACCOUNT|VM_WRITE|VM_SHARED))) {
+		if (!(oldflags & (VM_ACCOUNT|VM_WRITE|
+						VM_SHARED|VM_NORESERVE))) {
 			charged = nrpages;
 			if (security_vm_enough_memory(charged))
 				return -ENOMEM;