mm: vmalloc: don't remove inexistent guard hole in remove_vm_area()

Commit 71394fe501 ("mm: vmalloc: add flag preventing guard hole
allocation") missed a spot.  Currently remove_vm_area() decreases vm->size
to "remove" the guard hole page, even when it isn't present.  All but one
users just free the vm_struct rigth away and never access vm->size anyway.

Don't touch the size in remove_vm_area() and have __vunmap() use the
proper get_vm_area_size() helper.

Signed-off-by: Jerome Marchand <jmarchan@redhat.com>
Acked-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Jerome Marchand 2015-11-20 15:57:02 -08:00 коммит произвёл Linus Torvalds
Родитель 429d48622c
Коммит 7511c3ede7
1 изменённых файлов: 2 добавлений и 3 удалений

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@ -1443,7 +1443,6 @@ struct vm_struct *remove_vm_area(const void *addr)
vmap_debug_free_range(va->va_start, va->va_end);
kasan_free_shadow(vm);
free_unmap_vmap_area(va);
vm->size -= PAGE_SIZE;
return vm;
}
@ -1468,8 +1467,8 @@ static void __vunmap(const void *addr, int deallocate_pages)
return;
}
debug_check_no_locks_freed(addr, area->size);
debug_check_no_obj_freed(addr, area->size);
debug_check_no_locks_freed(addr, get_vm_area_size(area));
debug_check_no_obj_freed(addr, get_vm_area_size(area));
if (deallocate_pages) {
int i;