linux-sg2042/mm
Hugh Dickins 5b280c0cc7 mm: don't return 0 too early from find_get_pages()
Callers of find_get_pages(), or its wrapper pagevec_lookup() - notably
truncate_inode_pages_range() - stop looking further when it returns 0.

But if an interrupt comes just after its radix_tree_gang_lookup_slot(),
especially if we have preemptible RCU enabled, isn't it conceivable that
all 14 pages returned could be removed from the page cache by
shrink_page_list(), before find_get_pages() gets to process them?  So
causing it to return 0 although there may be plenty more pages beyond.

Make find_get_pages() and find_get_pages_tag() check for this unlikely
case, and restart should it occur; but callers of find_get_pages_contig()
have no such expectation, it's okay for that to return 0 early.

I have not seen this in practice, just worried by the possibility.

Signed-off-by: Hugh Dickins <hughd@google.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Salman Qazi <sqazi@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-03-22 17:44:04 -07:00
..
Kconfig mm: compaction: don't depend on HUGETLB_PAGE 2011-01-26 10:50:02 +10:00
Kconfig.debug mm: debug-pagealloc: fix kconfig dependency warning 2011-03-22 17:44:02 -07:00
Makefile bootmem: Separate out CONFIG_NO_BOOTMEM code into nobootmem.c 2011-02-24 14:43:05 +01:00
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 bootmem: Move contig_page_data definition to bootmem.c/nobootmem.c 2011-02-24 14:43:06 +01:00
bounce.c bounce: call flush_dcache_page() after bounce_copy_vec() 2010-09-09 18:57:25 -07:00
compaction.c mm/compaction: check migrate_pages's return value instead of list_empty() 2011-03-22 17:44:00 -07:00
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: don't return 0 too early from find_get_pages() 2011-03-22 17:44:04 -07:00
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+memcg-numa: fix BUG at include/linux/mm.h:370! 2011-03-14 08:29:50 -07:00
hugetlb.c hugetlbfs: correct handling of negative input to /proc/sys/vm/nr_hugepages 2011-03-22 17:44:04 -07:00
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 mm: export __get_user_pages 2011-03-17 13:08:27 -03:00
kmemcheck.c kmemcheck: Fix build errors due to missing slab.h 2010-03-30 22:02:32 +09:00
kmemleak-test.c kmemleak: remove memset by using kzalloc 2011-01-27 18:31:51 +00:00
kmemleak.c kmemleak: Allow kmemleak metadata allocations to fail 2011-01-27 18:32:06 +00:00
ksm.c mm: rename drop_anon_vma() to put_anon_vma() 2011-03-22 17:44:03 -07:00
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: don't adjust size in memblock_find_base() 2011-02-11 16:12:20 -08:00
memcontrol.c pagewalk: only split huge pages when necessary 2011-03-22 17:44:04 -07:00
memory-failure.c mm: change __remove_from_page_cache() 2011-03-22 17:44:02 -07:00
memory.c mm: allow GUP to fail instead of waiting on a page 2011-03-22 17:44:02 -07:00
memory_hotplug.c Merge branch 'slub/hotplug' into slab/urgent 2011-01-15 13:28:17 +02:00
mempolicy.c mempolicy: remove redundant check in __mpol_equal() 2011-03-22 17:44:04 -07:00
mempool.c mm: remove broken 'kzalloc' mempool 2009-09-22 07:17:35 -07:00
migrate.c mm: rename drop_anon_vma() to put_anon_vma() 2011-03-22 17:44:03 -07:00
mincore.c thp: mincore transparent hugepage support 2011-01-13 17:32:44 -08:00
mlock.c mlock: operate on any regions with protection != PROT_NONE 2011-02-02 10:20:50 +11:00
mm_init.c
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 mm: fix possible cause of a page_mapped BUG 2011-02-23 21:55:06 -08:00
msync.c sanitize vfs_fsync calling conventions 2010-05-21 18:31:21 -04:00
nobootmem.c bootmem: Move __alloc_memory_core_early() to nobootmem.c 2011-02-24 14:43:06 +01:00
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: suppress nodes that are not allowed from meminfo on oom kill 2011-03-22 17:44:01 -07:00
page-writeback.c mm: reclaim invalidated page ASAP 2011-03-22 17:44:04 -07:00
page_alloc.c mm: batch-free pcp list if possible 2011-03-22 17:44:02 -07:00
page_cgroup.c mm: notifier_from_errno() cleanup 2011-03-22 17:44:01 -07:00
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 pagewalk: only split huge pages when necessary 2011-03-22 17:44:04 -07:00
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 mm/pgtable-generic.c: fix CONFIG_SWAP=n build 2011-01-26 10:49:58 +10:00
prio_tree.c
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 mm: simplify anon_vma refcounts 2011-03-22 17:44:03 -07:00
shmem.c mm: shmem: change remove_from_page_cache 2011-03-22 17:44:02 -07:00
slab.c mm: notifier_from_errno() cleanup 2011-03-22 17:44:01 -07:00
slob.c mm: Remove support for kmem_cache_name() 2011-01-23 21:00:05 +02:00
slub.c slub: Add statistics for this_cmpxchg_double failures 2011-03-22 20:48:04 +02:00
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 mm: reclaim invalidated page ASAP 2011-03-22 17:44:04 -07:00
swap_state.c thp: split_huge_page paging 2011-01-13 17:32:41 -08:00
swapfile.c mm: swap: unlock swapfile inode mutex before closing file on bad swapfiles 2011-03-22 17:43:58 -07:00
thrash.c mm: pass mm to grab_swap_token 2009-06-23 12:50:05 -07:00
truncate.c mm: deactivate invalidated pages 2011-03-22 17:44:03 -07:00
util.c kernel: kmem_ptr_validate considered harmful 2011-01-07 17:50:16 +11:00
vmalloc.c mm: vmap area cache 2011-03-22 17:44:00 -07:00
vmscan.c mm: vmscan: kswapd should not free an excessive number of pages when balancing small zones 2011-03-22 17:44:04 -07:00
vmstat.c thp: transparent hugepage vmstat 2011-01-13 17:32:43 -08:00