Vladimir Davydov b8529907ba memcg, slab: do not destroy children caches if parent has aliases ... Currently we destroy children caches at the very beginning of kmem_cache_destroy(). This is wrong, because the root cache will not necessarily be destroyed in the end - if it has aliases (refcount > 0), kmem_cache_destroy() will simply decrement its refcount and return. In this case, at best we will get a bunch of warnings in dmesg, like this one: kmem_cache_destroy kmalloc-32:0: Slab cache still has objects CPU: 1 PID: 7139 Comm: modprobe Tainted: G B W 3.13.0+ #117 Call Trace: dump_stack+0x49/0x5b kmem_cache_destroy+0xdf/0xf0 kmem_cache_destroy_memcg_children+0x97/0xc0 kmem_cache_destroy+0xf/0xf0 xfs_mru_cache_uninit+0x21/0x30 [xfs] exit_xfs_fs+0x2e/0xc44 [xfs] SyS_delete_module+0x198/0x1f0 system_call_fastpath+0x16/0x1b At worst - if kmem_cache_destroy() will race with an allocation from a memcg cache - the kernel will panic. This patch fixes this by moving children caches destruction after the check if the cache has aliases. Plus, it forbids destroying a root cache if it still has children caches, because each children cache keeps a reference to its parent. Signed-off-by: Vladimir Davydov <vdavydov@parallels.com> Cc: Michal Hocko <mhocko@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Glauber Costa <glommer@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-04-07 16:36:13 -07:00
..
backing-dev.c	bdi: avoid oops on device removal	2014-04-03 16:20:49 -07:00
balloon_compaction.c	mm: print more details for bad_page()	2014-01-23 16:36:50 -08:00
bootmem.c	mm/bootmem.c: remove unused local `map'	2013-11-13 12:09:09 +09:00
bounce.c	block: Convert bio_for_each_segment() to bvec_iter	2013-11-23 22:33:49 -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
compaction.c	mm, compaction: determine isolation mode only once	2014-04-07 16:35:55 -07:00
debug-pagealloc.c
dmapool.c
fadvise.c
failslab.c
filemap.c	memcg: rename high level charging functions	2014-04-07 16:35:57 -07:00
filemap_xip.c	seqcount: Add lockdep functionality to seqcount/seqlock structures	2013-11-06 12:40:26 +01:00
fremap.c	mm: fix bad rss-counter if remap_file_pages raced migration	2014-03-19 16:21:49 -07:00
frontswap.c	frontswap: fix incorrect zeroing and allocation size for frontswap_map	2013-06-12 16:29:46 -07:00
highmem.c
huge_memory.c	memcg: rename high level charging functions	2014-04-07 16:35:57 -07:00
hugetlb.c	mm: hugetlb: fix softlockup when a large number of hugepages are freed.	2014-04-07 16:35:58 -07:00
hugetlb_cgroup.c	cgroup: drop const from @buffer of cftype->write_string()	2014-03-19 10:23:54 -04:00
hwpoison-inject.c	mm/hwpoison: add '#' to hwpoison_inject	2014-01-21 16:19:48 -08:00
init-mm.c
internal.h	mm/readahead.c: inline ra_submit	2014-04-07 16:35:58 -07:00
interval_tree.c
Kconfig	mm: disable split page table lock for !MMU	2014-04-07 16:35:52 -07:00
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c	kmemleak: change some global variables to int	2014-04-03 16:20:50 -07:00
ksm.c	mm: close PageTail race	2014-03-04 07:55:47 -08:00
list_lru.c	mm: keep page cache radix tree nodes in check	2014-04-03 16:21:01 -07:00
maccess.c
madvise.c	mm/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood	2013-09-30 14:31:02 -07:00
Makefile	mm: per-thread vma caching	2014-04-07 16:35:53 -07:00
memblock.c	mm/memblock.c: use PFN_PHYS()	2014-04-07 16:35:58 -07:00
memcontrol.c	memcg, slab: do not destroy children caches if parent has aliases	2014-04-07 16:36:13 -07:00
memory-failure.c	Merge branch 'for-3.15' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup	2014-04-03 13:05:42 -07:00
memory.c	mm: remove unused arg of set_page_dirty_balance()	2014-04-07 16:35:57 -07:00
memory_hotplug.c	mm/memory_hotplug.c: move register_memory_resource out of the lock_memory_hotplug	2014-01-23 16:36:52 -08:00
mempolicy.c	mm, mempolicy: remove per-process flag	2014-04-07 16:35:54 -07:00
mempool.c	mempool: add unlikely and likely hints	2014-04-07 16:35:55 -07:00
migrate.c	mm: fix swapops.h:131 bug if remap_file_pages raced migration	2014-03-20 22:09:09 -07:00
mincore.c	mm + fs: prepare for non-page entries in page cache radix trees	2014-04-03 16:21:00 -07:00
mlock.c	mm: try_to_unmap_cluster() should lock_page() before mlocking	2014-04-07 16:35:57 -07:00
mm_init.c	mm: bring back /sys/kernel/mm	2014-01-27 21:02:39 -08:00
mmap.c	mm: per-thread vma caching	2014-04-07 16:35:53 -07:00
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	mm: audit/fix non-modular users of module_init in core code	2014-01-23 16:36:52 -08:00
mmzone.c	mm: numa: Change page last {nid,pid} into {cpu,pid}	2013-10-09 14:47:45 +02:00
mprotect.c	mm: move mmu notifier call from change_protection to change_pmd_range	2014-04-07 16:35:50 -07:00
mremap.c	mm: revert mremap pud_free anti-fix	2013-10-16 21:35:53 -07:00
msync.c
nobootmem.c	mm/nobootmem.c: mark function as static	2014-04-03 16:21:02 -07:00
nommu.c	mm: fix 'ERROR: do not initialise globals to 0 or NULL' and coding style	2014-04-07 16:35:55 -07:00
oom_kill.c	mm, oom: base root bonus on current usage	2014-01-30 16:56:56 -08:00
page-writeback.c	mm: remove unused arg of set_page_dirty_balance()	2014-04-07 16:35:57 -07:00
page_alloc.c	mm/page_alloc.c: change mm debug routines back to EXPORT_SYMBOL	2014-04-07 16:35:59 -07:00
page_cgroup.c	mm/page_cgroup.c: mark functions as static	2014-04-03 16:21:02 -07:00
page_io.c	Merge branch 'for-3.14/core' of git://git.kernel.dk/linux-block	2014-01-30 11:19:05 -08:00
page_isolation.c	mm: memory-hotplug: enable memory hotplug to handle hugepage	2013-09-11 15:57:48 -07:00
pagewalk.c	mm/pagewalk.c: fix walk_page_range() access of wrong PTEs	2013-10-30 14:27:03 -07:00
percpu-km.c
percpu-vm.c
percpu.c	percpu: renew the max_contig if we merge the head and previous block	2014-03-29 09:29:42 -04:00
pgtable-generic.c	mm: fix TLB flush race between migration, and change_protection_range	2013-12-18 19:04:51 -08:00
process_vm_access.c	mm/process_vm_access.c: mark function as static	2014-04-03 16:21:02 -07:00
quicklist.c
readahead.c	mm/readahead.c: inline ra_submit	2014-04-07 16:35:58 -07:00
rmap.c	mm: try_to_unmap_cluster() should lock_page() before mlocking	2014-04-07 16:35:57 -07:00
shmem.c	memcg: rename high level charging functions	2014-04-07 16:35:57 -07:00
slab.c	mm, mempolicy: remove per-process flag	2014-04-07 16:35:54 -07:00
slab.h	memcg, slab: never try to merge memcg caches	2014-04-07 16:36:12 -07:00
slab_common.c	memcg, slab: do not destroy children caches if parent has aliases	2014-04-07 16:36:13 -07:00
slob.c	mm/sl[aou]b: Move kmallocXXX functions to common code	2013-09-04 20:51:33 +03:00
slub.c	memcg, slab: never try to merge memcg caches	2014-04-07 16:36:12 -07:00
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: thrash detection-based file cache sizing	2014-04-03 16:21:01 -07:00
swap_state.c	swap: add a simple detector for inappropriate swapin readahead	2014-02-06 13:48:51 -08:00
swapfile.c	mm/swap: fix race on swap_info reuse between swapoff and swapon	2014-02-06 13:48:51 -08:00
truncate.c	mm: keep page cache radix tree nodes in check	2014-04-03 16:21:01 -07:00
util.c	mm: use macros from compiler.h instead of __attribute__((...))	2014-04-07 16:35:54 -07:00
vmacache.c	mm: per-thread vma caching	2014-04-07 16:35:53 -07:00
vmalloc.c	mm/vmalloc.c: enhance vm_map_ram() comment	2014-04-07 16:35:55 -07:00
vmpressure.c	arm, pm, vmpressure: add missing slab.h includes	2014-02-03 13:24:01 -05:00
vmscan.c	mm/vmscan: do not check compaction_ready on promoted zones	2014-04-07 16:35:50 -07:00
vmstat.c	drop_caches: add some documentation and info message	2014-04-03 16:21:04 -07:00
workingset.c	mm: keep page cache radix tree nodes in check	2014-04-03 16:21:01 -07:00
zbud.c	mm/zbud: fix some trivial typos in comments	2013-09-11 15:57:35 -07:00
zsmalloc.c	zsmalloc: add copyright	2014-01-30 16:56:55 -08:00
zswap.c	mm/zswap.c: remove unnecessary parentheses	2014-04-07 16:36:03 -07:00