1
0
Fork 0
alistair23-linux/mm
Hugh Dickins 1ce82b69e9 mm: fix migration hangs on anon_vma lock
Increased usage of page migration in mmotm reveals that the anon_vma
locking in unmap_and_move() has been deficient since 2.6.36 (or even
earlier).  Review at the time of f18194275c
("mm: fix hang on anon_vma->root->lock") missed the issue here: the
anon_vma to which we get a reference may already have been freed back to
its slab (it is in use when we check page_mapped, but that can change),
and so its anon_vma->root may be switched at any moment by reuse in
anon_vma_prepare.

Perhaps we could fix that with a get_anon_vma_unless_zero(), but let's
not: just rely on page_lock_anon_vma() to do all the hard thinking for us,
then we don't need any rcu read locking over here.

In removing the rcu_unlock label: since PageAnon is a bit in
page->mapping, it's impossible for a !page->mapping page to be anon; but
insert VM_BUG_ON in case the implementation ever changes.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Hugh Dickins <hughd@google.com>
Reviewed-by: Mel Gorman <mel@csn.ul.ie>
Reviewed-by: Rik van Riel <riel@redhat.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: "Jun'ichi Nomura" <j-nomura@ce.jp.nec.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: <stable@kernel.org> [2.6.37, 2.6.36]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-01-13 17:32:49 -08:00
..
Kconfig thp: select CONFIG_COMPACTION if TRANSPARENT_HUGEPAGE enabled 2011-01-13 17:32:45 -08:00
Kconfig.debug trivial: improve help text for mm debug config options 2009-09-21 15:14:57 +02:00
Makefile thp: transparent hugepage core 2011-01-13 17:32:42 -08:00
backing-dev.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2010-10-26 17:58:44 -07:00
bootmem.c x86, memblock: Replace e820_/_early string with memblock_ 2010-08-27 11:13:47 -07:00
bounce.c bounce: call flush_dcache_page() after bounce_copy_vec() 2010-09-09 18:57:25 -07:00
compaction.c thp: use compaction for all allocation orders 2011-01-13 17:32:46 -08:00
debug-pagealloc.c generic debug pagealloc 2009-04-01 08:59:13 -07:00
dmapool.c mm/dmapool.c: use TASK_UNINTERRUPTIBLE in dma_pool_alloc() 2011-01-13 17:32:48 -08:00
fadvise.c readahead: introduce FMODE_RANDOM for POSIX_FADV_RANDOM 2010-03-06 11:26:25 -08:00
failslab.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
filemap.c mm: remove likely() from grab_cache_page_write_begin() 2011-01-13 17:32:36 -08:00
filemap_xip.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
fremap.c Avoid pgoff overflow in remap_file_pages 2010-09-25 09:34:58 -07:00
highmem.c mm,x86: fix kmap_atomic_push vs ioremap_32.c 2010-10-27 18:03:05 -07:00
huge_memory.c thp: khugepaged: make khugepaged aware about madvise 2011-01-13 17:32:47 -08:00
hugetlb.c hugetlb: fix handling of parse errors in sysfs 2011-01-13 17:32:49 -08:00
hwpoison-inject.c HWPOISON, hugetlb: support hwpoison injection for hugepage 2010-08-11 09:23:11 +02:00
init-mm.c mm: provide init_mm mm_context initializer 2010-08-09 20:44:54 -07:00
internal.h thp: transparent hugepage core 2011-01-13 17:32:42 -08:00
kmemcheck.c kmemcheck: Fix build errors due to missing slab.h 2010-03-30 22:02:32 +09:00
kmemleak-test.c percpu: clean up percpu variable definitions 2009-06-24 15:13:48 +09:00
kmemleak.c kmemleak: Fix typo in the comment 2010-08-08 21:57:23 +01:00
ksm.c ksm: drain pagevecs to lru 2011-01-13 17:32:49 -08:00
maccess.c MN10300: Save frame pointer in thread_info struct rather than global var 2010-10-27 17:29:01 +01:00
madvise.c thp: khugepaged: make khugepaged aware about madvise 2011-01-13 17:32:47 -08:00
memblock.c memblock: Annotate memblock functions with __init_memblock 2010-10-11 16:00:52 -07:00
memcontrol.c thp: compound_trans_order 2011-01-13 17:32:47 -08:00
memory-failure.c thp: compound_trans_order 2011-01-13 17:32:47 -08:00
memory.c thp: add debug checks for mapcount related invariants 2011-01-13 17:32:47 -08:00
memory_hotplug.c thp: remove PG_buddy 2011-01-13 17:32:43 -08:00
mempolicy.c thp: add numa awareness to hugepage allocations 2011-01-13 17:32:45 -08:00
mempool.c mm: remove broken 'kzalloc' mempool 2009-09-22 07:17:35 -07:00
migrate.c mm: fix migration hangs on anon_vma lock 2011-01-13 17:32:49 -08:00
mincore.c thp: mincore transparent hugepage support 2011-01-13 17:32:44 -08:00
mlock.c mlock: do not hold mmap_sem for extended periods of time 2011-01-13 17:32:36 -08:00
mm_init.c mm: mminit_loglevel cannot be __meminitdata anymore 2008-08-20 15:40:30 -07:00
mmap.c brk: fix min_brk lower bound computation for COMPAT_BRK 2011-01-13 17:32:48 -08:00
mmu_context.c exit: fix oops in sync_mm_rss 2010-03-24 16:31:21 -07:00
mmu_notifier.c thp: mmu_notifier_test_young 2011-01-13 17:32:46 -08:00
mmzone.c mm: page allocator: adjust the per-cpu counter threshold when memory is low 2011-01-13 17:32:31 -08:00
mprotect.c thp: mprotect: transparent huge page support 2011-01-13 17:32:44 -08:00
mremap.c thp: split_huge_page_mm/vma 2011-01-13 17:32:41 -08:00
msync.c sanitize vfs_fsync calling conventions 2010-05-21 18:31:21 -04:00
nommu.c mlock: do not hold mmap_sem for extended periods of time 2011-01-13 17:32:36 -08:00
oom_kill.c oom: kill all threads sharing oom killed task's mm 2010-10-26 16:52:05 -07:00
page-writeback.c writeback: avoid unnecessary determine_dirtyable_memory call 2011-01-13 17:32:38 -08:00
page_alloc.c mm/page_alloc.c: simplify calculation of combined index of adjacent buddy lists 2011-01-13 17:32:48 -08:00
page_cgroup.c kmemleak: Annotate false positive in init_section_page_cgroup() 2010-07-19 11:54:14 +01:00
page_io.c block: unify flags for struct bio and struct request 2010-08-07 18:20:39 +02:00
page_isolation.c mm: page_isolation: codeclean fix comment and rm unneeded val init 2010-10-26 16:52:11 -07:00
pagewalk.c thp: split_huge_page_mm/vma 2011-01-13 17:32:41 -08:00
percpu-km.c percpu: clear memory allocated with the km allocator 2010-10-02 10:28:42 +03:00
percpu-vm.c mm: remove gfp mask from pcpu_get_vm_areas 2011-01-13 17:32:34 -08:00
percpu.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial 2011-01-13 10:05:56 -08:00
pgtable-generic.c thp: add pmd mangling generic functions 2011-01-13 17:32:40 -08:00
prio_tree.c spelling fixes: mm/ 2007-10-20 01:27:18 +02:00
quicklist.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
readahead.c readahead.c: fix comment 2010-05-25 08:07:00 -07:00
rmap.c thp: fix memory-failure hugetlbfs vs THP collision 2011-01-13 17:32:47 -08:00
shmem.c fs: icache RCU free inodes 2011-01-07 17:50:26 +11:00
slab.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/slab-2.6 2011-01-10 08:38:01 -08:00
slob.c kernel: kmem_ptr_validate considered harmful 2011-01-07 17:50:16 +11:00
slub.c mm: convert sprintf_symbol to %pS 2011-01-13 17:32:33 -08:00
sparse-vmemmap.c tree-wide: fix comment/printk typos 2010-11-01 15:38:34 -04:00
sparse.c thp: remove PG_buddy 2011-01-13 17:32:43 -08:00
swap.c thp: transparent hugepage core 2011-01-13 17:32:42 -08:00
swap_state.c thp: split_huge_page paging 2011-01-13 17:32:41 -08:00
swapfile.c thp: split_huge_page paging 2011-01-13 17:32:41 -08:00
thrash.c mm: pass mm to grab_swap_token 2009-06-23 12:50:05 -07:00
truncate.c Call the filesystem back whenever a page is removed from the page cache 2010-12-02 09:55:21 -05:00
util.c kernel: kmem_ptr_validate considered harmful 2011-01-07 17:50:16 +11:00
vmalloc.c vmalloc: remove redundant unlikely() 2011-01-13 17:32:36 -08:00
vmscan.c thp: scale nr_rotated to balance memory pressure 2011-01-13 17:32:46 -08:00
vmstat.c thp: transparent hugepage vmstat 2011-01-13 17:32:43 -08:00