linux/mm
Martijn Coenen ab0d430c52 memcg: only free spare array when readers are done
[ Upstream commit 6611d8d761 ]

A spare array holding mem cgroup threshold events is kept around to make
sure we can always safely deregister an event and have an array to store
the new set of events in.

In the scenario where we're going from 1 to 0 registered events, the
pointer to the primary array containing 1 event is copied to the spare
slot, and then the spare slot is freed because no events are left.
However, it is freed before calling synchronize_rcu(), which means
readers may still be accessing threshold->primary after it is freed.

Fixed by only freeing after synchronize_rcu().

Signed-off-by: Martijn Coenen <maco@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vladimir Davydov <vdavydov@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
History 2016-02-09 22:57:10 -05:00
..
backing-dev.c Merge branch 'for-3.18/core' of git://git.kernel.dk/linux-block 2014-10-18 11:53:51 -07:00
balloon_compaction.c virtio_balloon: fix race between migration and ballooning 2016-02-09 22:56:37 -05:00
bootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-13 16:17:06 -08:00
cleancache.c mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE 2014-01-23 16:36:50 -08:00
cma.c mm/CMA: fix boot regression due to physical address of high_memory 2015-01-08 10:30:28 -08:00
compaction.c mm: fix negative nr_isolated counts 2015-03-14 15:37:16 -04:00
debug-pagealloc.c mm, x86: Remove debug_pagealloc_enabled 2011-12-06 09:24:07 +01:00
debug.c mm/debug.c: use pr_emerg() 2014-10-09 22:25:59 -04:00
dmapool.c mm/dmapool.c: fixed a brace coding style issue 2014-10-09 22:26:00 -04:00
early_ioremap.c mm: create generic early_ioremap() support 2014-04-07 16:36:15 -07:00
fadvise.c teach SYSCALL_DEFINE<n> how to deal with long long/unsigned long long 2013-03-03 22:46:22 -05:00
failslab.c switch debugfs to umode_t 2012-01-03 22:54:56 -05:00
filemap.c mm: make sendfile(2) killable 2015-11-15 12:51:48 -05:00
filemap_xip.c seqcount: Add lockdep functionality to seqcount/seqlock structures 2013-11-06 12:40:26 +01:00
fremap.c mm: mark remap_file_pages() syscall as deprecated 2014-06-06 16:08:17 -07:00
frontswap.c mm: frontswap: invalidate expired data on a dup-store failure 2014-12-02 17:32:07 -08:00
gup.c mm/hugetlb: take page table lock in follow_huge_pmd() 2015-05-17 19:12:31 -04:00
highmem.c mm/highmem: make kmap cache coloring aware 2014-08-06 18:01:22 -07:00
huge_memory.c mm, thp: fix collapsing of hugepages on madvise 2014-10-29 16:33:14 -07:00
hugetlb.c mm: hugetlbfs: skip shared VMAs when unmapping private pages to satisfy a fault 2015-10-27 22:13:20 -04:00
hugetlb_cgroup.c hugetlb_cgroup: use lockdep_assert_held rather than spin_is_locked 2014-08-29 16:28:16 -07:00
hwpoison-inject.c mm/hwpoison-inject.c: remove unnecessary null test before debugfs_remove_recursive 2014-08-06 18:01:19 -07:00
init-mm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
internal.h mm/page_alloc: restrict max order of merging on isolated pageblock 2014-11-13 16:17:05 -08:00
interval_tree.c mm: convert a few VM_BUG_ON callers to VM_BUG_ON_VMA 2014-10-09 22:25:57 -04:00
iov_iter.c Fix thinko in iov_iter_single_seg_count 2014-11-13 13:28:55 -05:00
Kconfig mm/balloon_compaction: add vmstat counters and kpageflags bit 2014-10-09 22:26:01 -04:00
Kconfig.debug mm: more intensive memory corruption debugging 2012-01-10 16:30:42 -08:00
kmemcheck.c mm/slab_common: move kmem_cache definition to internal header 2014-10-09 22:25:50 -04:00
kmemleak-test.c mm/kmemleak-test.c: use pr_fmt for logging 2014-06-06 16:08:18 -07:00
kmemleak.c mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc() 2015-07-05 10:12:51 -04:00
ksm.c vm: add VM_FAULT_SIGSEGV handling support 2015-02-05 22:36:01 -08:00
list_lru.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
maccess.c mm: Map most files to use export.h instead of module.h 2011-10-31 09:20:12 -04:00
madvise.c mm: update the description for madvise_remove 2014-08-06 18:01:18 -07:00
Makefile Fixup for 3.18: use PATCHv2 of "mm: Support compiling out madvise and fadvise" 2014-10-12 09:21:57 -04:00
memblock.c mem-hotplug: let memblock skip the hotpluggable memory regions in __next_mem_range() 2014-09-10 15:42:12 -07:00
memcontrol.c memcg: only free spare array when readers are done 2016-02-09 22:57:10 -05:00
memory-failure.c mm: soft-offline: check return value in second __get_any_page() call 2016-02-09 22:57:09 -05:00
memory.c mmu_gather: move minimal range calculations into generic code 2015-03-28 09:22:01 -04:00
memory_hotplug.c mm/memory_hotplug.c: set zone->wait_table to null after freeing it 2015-07-03 12:34:45 -04:00
mempolicy.c mm, numa: really disable NUMA balancing by default on single node machines 2015-06-10 13:42:34 -04:00
mempool.c mm/mempool.c: update the kmemleak stack trace for mempool allocations 2014-06-06 16:08:17 -07:00
migrate.c mm/hugetlb: take page table lock in follow_huge_pmd() 2015-05-17 19:12:31 -04:00
mincore.c mm + fs: prepare for non-page entries in page cache radix trees 2014-04-03 16:21:00 -07:00
mlock.c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-10-13 15:44:12 +02:00
mm_init.c mm: bring back /sys/kernel/mm 2014-01-27 21:02:39 -08:00
mmap.c mm: fix anon_vma->degree underflow in anon_vma endless growing prevention 2015-04-24 17:13:38 -04:00
mmu_context.c sched/mm: call finish_arch_post_lock_switch in idle_task_exit and use_mm 2014-02-21 08:50:17 +01:00
mmu_notifier.c kvm: Fix page ageing bugs 2014-09-24 14:07:58 +02:00
mmzone.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mprotect.c mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared 2014-10-14 02:18:28 +02:00
mremap.c mm/mremap.c: use linux headers 2014-10-09 22:26:00 -04:00
msync.c msync: fix incorrect fstart calculation 2014-07-03 09:21:53 -07:00
nobootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-13 16:17:06 -08:00
nommu.c mm/nommu.c: fix arithmetic overflow in __vm_enough_memory() 2015-03-14 15:37:16 -04:00
oom_kill.c OOM, PM: OOM killed task shouldn't escape PM suspend 2014-10-21 23:44:21 +02:00
page-writeback.c writeback: use |1 instead of +1 to protect against div by zero 2015-05-23 15:52:00 -04:00
page_alloc.c mm: when stealing freepages, also take pages created by splitting buddy page 2015-03-14 15:37:15 -04:00
page_cgroup.c cgroup/kmemleak: add kmemleak_free() for cgroup deallocations. 2014-10-29 16:33:13 -07:00
page_io.c fix __swap_writepage() compile failure on old gcc versions 2014-06-14 19:30:48 -05:00
page_isolation.c mm/page_alloc.c: call kernel_map_pages in unset_migrateype_isolate 2015-04-24 17:13:43 -04:00
pagewalk.c mm: pagewalk: call pte_hole() for VM_PFNMAP during walk_page_range 2015-02-11 15:00:53 +08:00
percpu-km.c percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated 2014-09-02 14:46:05 -04:00
percpu-vm.c percpu: move region iterations out of pcpu_[de]populate_chunk() 2014-09-02 14:46:02 -04:00
percpu.c mm: kmemleak_alloc_percpu() should follow the gfp from per_alloc() 2015-07-05 10:12:51 -04:00
pgtable-generic.c mm: actually clear pmd_numa before invalidating 2014-08-29 16:28:15 -07:00
process_vm_access.c start adding the tag to iov_iter 2014-05-06 17:32:49 -04:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm/readahead.c: remove unused file_ra_state from count_history_pages 2014-08-06 18:01:15 -07:00
rmap.c mm: fix anon_vma->degree underflow in anon_vma endless growing prevention 2015-04-24 17:13:38 -04:00
shmem.c memcg, shmem: fix shmem migration to use lrucare 2015-02-11 15:00:53 +08:00
slab.c mm/slab: fix unexpected index mapping result of kmalloc_size(INDEX_NODE+1) 2015-10-27 22:14:30 -04:00
slab.h mm/slab: use percpu allocator for cpu cache 2014-10-09 22:25:51 -04:00
slab_common.c mm/slab: fix unalignment problem on Malta with EVA due to slab merge 2014-11-13 16:17:05 -08:00
slob.c mm/sl[ao]b: always track caller in kmalloc_(node_)track_caller() 2014-10-09 22:25:50 -04:00
slub.c mm/slab_common: commonize slab merge logic 2014-10-09 22:25:51 -04:00
sparse-vmemmap.c mm/sparse: use memblock apis for early memory allocations 2014-01-21 16:19:47 -08:00
sparse.c mm: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:35:54 -07:00
swap.c mm: memcontrol: do not kill uncharge batching in free_pages_and_swap_cache 2014-10-09 22:25:59 -04:00
swap_state.c mm: memcontrol: do not kill uncharge batching in free_pages_and_swap_cache 2014-10-09 22:25:59 -04:00
swapfile.c mm: memcontrol: rewrite uncharge API 2014-08-08 15:57:17 -07:00
truncate.c mm: Fix comment before truncate_setsize() 2014-11-07 08:29:25 +11:00
util.c proc/maps: make vm_is_stack() logic namespace-friendly 2014-10-09 22:25:50 -04:00
vmacache.c mm,vmacache: optimize overflow system-wide flushing 2014-06-04 16:53:57 -07:00
vmalloc.c mm/vmalloc.c: use seq_open_private() instead of seq_open() 2014-10-09 22:25:56 -04:00
vmpressure.c mm/vmpressure.c: fix race in vmpressure_work_fn() 2014-12-02 17:32:07 -08:00
vmscan.c vmscan: fix increasing nr_isolated incurred by putback unevictable pages 2015-10-07 10:18:57 -04:00
vmstat.c vmstat: do not use deferrable delayed work for vmstat_update 2015-03-23 21:02:53 -04:00
workingset.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
zbud.c zbud: avoid accessing last unused freelist 2014-10-09 22:26:03 -04:00
zpool.c mm/zpool: use prefixed module loading 2014-08-29 16:28:16 -07:00
zsmalloc.c zsmalloc: simplify init_zspage free obj linking 2014-10-09 22:26:03 -04:00
zswap.c mm/zswap.c: add __init to zswap_entry_cache_destroy() 2014-08-08 15:57:18 -07:00