Commit 8757d5fa authored by Jan Kiszka's avatar Jan Kiszka Committed by Linus Torvalds
Browse files

[PATCH] mm: fix oom roll-back of __vmalloc_area_node 



__vunmap must not rely on area->nr_pages when picking the release methode
for area->pages.  It may be too small when __vmalloc_area_node failed early
due to lacking memory.  Instead, use a flag in vmstruct to differentiate.

Signed-off-by: default avatarJan Kiszka <jan.kiszka@web.de>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent e322fedf

include/linux/vmalloc.h

+1 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ struct vm_area_struct; 
#define VM_ALLOC	0x00000002	/* vmalloc() */

#define VM_MAP		0x00000004	/* vmap()ed pages */

#define VM_USERMAP	0x00000008	/* suitable for remap_vmalloc_range */

#define VM_VPAGES	0x00000010	/* buffer for pages was vmalloc'ed */

/* bits [20..32] reserved for arch specific ioremap internals */



/*

mm/vmalloc.c

+4 −3
Original line number Diff line number Diff line
@@ -340,7 +340,7 @@ void __vunmap(void *addr, int deallocate_pages) 
			__free_page(area->pages[i]);

		}



		if (area->nr_pages > PAGE_SIZE/sizeof(struct page *))

		if (area->flags & VM_VPAGES)

			vfree(area->pages);

		else

			kfree(area->pages);
@@ -427,9 +427,10 @@ void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, 


	area->nr_pages = nr_pages;

	/* Please note that the recursion is strictly bounded. */

	if (array_size > PAGE_SIZE)

	if (array_size > PAGE_SIZE) {

		pages = __vmalloc_node(array_size, gfp_mask, PAGE_KERNEL, node);

	else

		area->flags |= VM_VPAGES;

	} else

		pages = kmalloc_node(array_size, (gfp_mask & ~__GFP_HIGHMEM), node);

	area->pages = pages;

	if (!area->pages) {

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