diff options
| -rw-r--r-- | include/linux/mm.h | 1 | ||||
| -rw-r--r-- | mm/mmap.c | 3 | ||||
| -rw-r--r-- | mm/mprotect.c | 6 |
3 files changed, 6 insertions, 4 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index 196924b657bc..df322fb4df31 100644 --- a/include/linux/mm.h +++ b/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) */ diff --git a/mm/mmap.c b/mm/mmap.c index 75e0d0673d78..57d3b6097deb 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -1110,6 +1110,9 @@ munmap_back: 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) { diff --git a/mm/mprotect.c b/mm/mprotect.c index 360d9cc8b38c..abd645a3b0a0 100644 --- a/mm/mprotect.c +++ b/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; |