d98c7a0984
Somehow I imagined that calling a NULL destructor would free a compound page rather than oopsing. No, we must supply a default destructor, __free_pages_ok using the order noted by prep_compound_page. hugetlb can still replace this as before with its own free_huge_page pointer. The case that needs this is not common: rarely does put_compound_page's put_page_testzero bring the count down to 0. But if get_user_pages is applied to some part of a compound page, without immediate release (e.g. AIO or Infiniband), then it's possible for its put_page to come after the containing vma has been unmapped and the driver done its free_pages. That's just the kind of case compound pages are supposed to be guarding against (but Nick points out, nor did PageReserved handle this right). Signed-off-by: Hugh Dickins <hugh@veritas.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| bootmem.c | ||
| fadvise.c | ||
| filemap_xip.c | ||
| filemap.c | ||
| filemap.h | ||
| fremap.c | ||
| highmem.c | ||
| hugetlb.c | ||
| internal.h | ||
| Kconfig | ||
| madvise.c | ||
| Makefile | ||
| memory_hotplug.c | ||
| memory.c | ||
| mempolicy.c | ||
| mempool.c | ||
| mincore.c | ||
| mlock.c | ||
| mmap.c | ||
| mprotect.c | ||
| mremap.c | ||
| msync.c | ||
| nommu.c | ||
| oom_kill.c | ||
| page_alloc.c | ||
| page_io.c | ||
| page-writeback.c | ||
| pdflush.c | ||
| prio_tree.c | ||
| readahead.c | ||
| rmap.c | ||
| shmem.c | ||
| slab.c | ||
| slob.c | ||
| sparse.c | ||
| swap_state.c | ||
| swap.c | ||
| swapfile.c | ||
| thrash.c | ||
| tiny-shmem.c | ||
| truncate.c | ||
| util.c | ||
| vmalloc.c | ||
| vmscan.c | ||