alistair23-linux/mm
Tim Chen a2e1673172 mm/swap_slots.c: fix race conditions in swap_slots cache init
Memory allocations can happen before the swap_slots cache initialization
is completed during cpu bring up.  If we are low on memory, we could
call get_swap_page() and access swap_slots_cache before it is fully
initialized.

Add a check in get_swap_page() for initialized swap_slots_cache to
prevent this condition.  Similar check already exists in free_swap_slot.
Also annotate the checks to indicate the likely condition.

We also added a memory barrier to make sure that the locks
initialization are done before the assignment of cache->slots and
cache->slots_ret pointers.  This ensures the assumption that it is safe
to acquire the slots cache locks and use the slots cache when the
corresponding cache->slots or cache->slots_ret pointers are non null.

[akpm@linux-foundation.org: tidy up comment]
[akpm@linux-foundation.org: fix spello in comment]
Link: http://lkml.kernel.org/r/65a9d0f133f63e66bba37b53b2fd0464b7cae771.1500677066.git.tim.c.chen@linux.intel.com
Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Reported-by: Wenwei Tao <wenwei.tww@alibaba-inc.com>
Acked-by: Ying Huang <ying.huang@intel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Hillf Danton <hdanton@sina.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-11-15 18:21:03 -08:00
..
kasan slab, slub, slob: add slab_flags_t 2017-11-15 18:21:01 -08:00
backing-dev.c backing-dev: kill unused pdflush_proc_obsolete() 2017-10-06 08:15:15 -06:00
balloon_compaction.c mm/migrate: new migrate mode MIGRATE_SYNC_NO_COPY 2017-09-08 18:26:46 -07:00
bootmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cleancache.c
cma.c mm/cma.c: take __GFP_NOWARN into account in cma_alloc() 2017-10-13 16:18:32 -07:00
cma.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cma_debug.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
compaction.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debug.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debug_page_ref.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
dmapool.c
early_ioremap.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
fadvise.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
failslab.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
filemap.c mm: have filemap_check_and_advance_wb_err clear AS_EIO/AS_ENOSPC 2017-10-03 17:54:24 -07:00
frame_vector.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
frontswap.c
gup.c Merge branch 'x86/urgent' into x86/mm, to pick up fixes 2017-10-20 13:06:52 +02:00
highmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
hmm.c mm/hmm: avoid bloating arch that do not make use of HMM 2017-09-08 18:26:46 -07:00
huge_memory.c mm/mmu_notifier: avoid call to invalidate_range() in range_end() 2017-11-15 18:21:03 -08:00
hugetlb.c mm/mmu_notifier: avoid double notification when it is useless 2017-11-15 18:21:03 -08:00
hugetlb_cgroup.c
hwpoison-inject.c
init-mm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
internal.h mm, oom: do not rely on TIF_MEMDIE for memory reserves access 2017-09-06 17:27:30 -07:00
interval_tree.c lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
Kconfig mm/hmm: avoid bloating arch that do not make use of HMM 2017-09-08 18:26:46 -07:00
Kconfig.debug
khugepaged.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kmemcheck.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
kmemleak-test.c
kmemleak.c
ksm.c mm/mmu_notifier: avoid double notification when it is useless 2017-11-15 18:21:03 -08:00
list_lru.c mm: memcontrol: use vmalloc fallback for large kmem memcg arrays 2017-10-03 17:54:25 -07:00
maccess.c
madvise.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
memblock.c mm/memblock.c: make the index explicit argument of for_each_memblock_type 2017-11-15 18:21:02 -08:00
memcontrol.c mm: slabinfo: remove CONFIG_SLABINFO 2017-11-15 18:21:01 -08:00
memory-failure.c
memory.c mm/mmu_notifier: avoid call to invalidate_range() in range_end() 2017-11-15 18:21:03 -08:00
memory_hotplug.c mm, memory_hotplug: remove timeout from __offline_memory 2017-11-15 18:21:02 -08:00
mempolicy.c mm/mempolicy: fix NUMA_INTERLEAVE_HIT counter 2017-10-13 16:18:32 -07:00
mempool.c mm/mempool.c: use kmalloc_array_node() 2017-11-15 18:21:02 -08:00
memtest.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
migrate.c mm/mmu_notifier: avoid call to invalidate_range() in range_end() 2017-11-15 18:21:03 -08:00
mincore.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mlock.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mm_init.c
mmap.c lib/interval_tree: fast overlap detection 2017-09-08 18:26:49 -07:00
mmu_context.c
mmu_notifier.c mm/mmu_notifier: avoid call to invalidate_range() in range_end() 2017-11-15 18:21:03 -08:00
mmzone.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mprotect.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mremap.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
msync.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nobootmem.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
nommu.c Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-09-14 18:13:32 -07:00
oom_kill.c mm: oom: show unreclaimable slab info when unreclaimable slabs > user memory 2017-11-15 18:21:01 -08:00
page-writeback.c mm/page-writeback.c: print a warning if the vm dirtiness settings are illogical 2017-11-15 18:21:03 -08:00
page_alloc.c mm, page_alloc: fail has_unmovable_pages when seeing reserved pages 2017-11-15 18:21:02 -08:00
page_counter.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_ext.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_idle.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_io.c mm, swap: skip swapcache for swapin of synchronous device 2017-11-15 18:21:02 -08:00
page_isolation.c mm: distinguish CMA and MOVABLE isolation in has_unmovable_pages() 2017-11-15 18:21:02 -08:00
page_owner.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_poison.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
page_vma_mapped.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pagewalk.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
percpu-internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
percpu-km.c
percpu-stats.c percpu: fix starting offset for chunk statistics traversal 2017-09-27 14:45:57 -07:00
percpu-vm.c
percpu.c mm, percpu: add support for __GFP_NOWARN flag 2017-10-19 13:13:49 +01:00
pgtable-generic.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
process_vm_access.c
quicklist.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
readahead.c
rmap.c mm/mmu_notifier: avoid double notification when it is useless 2017-11-15 18:21:03 -08:00
rodata_test.c mm: fix RODATA_TEST failure "rodata_test: test data was not read only" 2017-10-03 17:54:24 -07:00
shmem.c mm: treewide: remove GFP_TEMPORARY allocation flag 2017-09-13 18:53:16 -07:00
slab.c slab, slub, slob: convert slab_flags_t to 32-bit 2017-11-15 18:21:01 -08:00
slab.h slab, slub, slob: add slab_flags_t 2017-11-15 18:21:01 -08:00
slab_common.c slab, slub, slob: add slab_flags_t 2017-11-15 18:21:01 -08:00
slob.c slab, slub, slob: add slab_flags_t 2017-11-15 18:21:01 -08:00
slub.c slub: fix sysfs duplicate filename creation when slub_debug=O 2017-11-15 18:21:01 -08:00
sparse-vmemmap.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
sparse.c Merge branch 'x86/mm' into x86/asm, to merge branches 2017-11-10 08:05:30 +01:00
swap.c mm: avoid marking swap cached page as lazyfree 2017-10-03 17:54:24 -07:00
swap_cgroup.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
swap_slots.c mm/swap_slots.c: fix race conditions in swap_slots cache init 2017-11-15 18:21:03 -08:00
swap_state.c mm, swap: fix false error message in __swp_swapcount() 2017-11-15 18:21:02 -08:00
swapfile.c mm: swap: SWP_SYNCHRONOUS_IO: skip swapcache only if swapped page has no other reference 2017-11-15 18:21:02 -08:00
truncate.c
usercopy.c
userfaultfd.c userfaultfd: shmem: wire up shmem_mfill_zeropage_pte 2017-09-06 17:27:28 -07:00
util.c mm: rename global_page_state to global_zone_page_state 2017-09-06 17:27:29 -07:00
vmacache.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
vmalloc.c Revert "vmalloc: back off when the current task is killed" 2017-10-13 16:18:32 -07:00
vmpressure.c
vmscan.c mm: remove unused pgdat->inactive_ratio 2017-11-15 18:21:03 -08:00
vmstat.c mm: remove unused pgdat->inactive_ratio 2017-11-15 18:21:03 -08:00
workingset.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
z3fold.c z3fold: fix stale list handling 2017-10-03 17:54:24 -07:00
zbud.c
zpool.c
zsmalloc.c zsmalloc: calling zs_map_object() from irq is a bug 2017-11-15 18:21:03 -08:00
zswap.c