OpenE2K/linux
6
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity
c2ce8c142c
linux/mm
History
Wanpeng Li c2ce8c142c mm/vmalloc: fix show vmap_area information race with vmap_area tear down 
There is a race window between vmap_area tear down and show vmap_area
information.

	A                                                B

remove_vm_area
spin_lock(&vmap_area_lock);
va->vm = NULL;
va->flags &= ~VM_VM_AREA;
spin_unlock(&vmap_area_lock);
						spin_lock(&vmap_area_lock);
						if (va->flags & (VM_LAZY_FREE | VM_LAZY_FREEZING))
							return 0;
						if (!(va->flags & VM_VM_AREA)) {
							seq_printf(m, "0x%pK-0x%pK %7ld vm_map_ram\n",
								(void *)va->va_start, (void *)va->va_end,
								va->va_end - va->va_start);
							return 0;
						}
free_unmap_vmap_area(va);
	flush_cache_vunmap
	free_unmap_vmap_area_noflush
		unmap_vmap_area
		free_vmap_area_noflush
			va->flags |= VM_LAZY_FREE

The assumption !VM_VM_AREA represents vm_map_ram allocation is
introduced by d4033afdf8 ("mm, vmalloc: iterate vmap_area_list,
instead of vmlist, in vmallocinfo()").

However, !VM_VM_AREA also represents vmap_area is being tear down in
race window mentioned above.  This patch fix it by don't dump any
information for !VM_VM_AREA case and also remove (VM_LAZY_FREE |
VM_LAZY_FREEING) check since they are not possible for !VM_VM_AREA case.

Suggested-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Acked-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Wanpeng Li <liwanp@linux.vnet.ibm.com>
Cc: Mitsuo Hayasaka <mitsuo.hayasaka.hu@hitachi.com>
Cc: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-13 12:09:05 +09:00
..
backing-dev.c mm/backing-dev.c: check user buffer length before copying data to the related user buffer 2013-09-11 15:58:03 -07:00
balloon_compaction.c
bootmem.c mm: use pgdat_end_pfn() to simplify the code in others 2013-11-13 12:09:03 +09:00
bounce.c mm/bounce.c: fix a regression where MS_SNAP_STABLE (stable pages snapshotting) was ignored 2013-09-30 14:31:02 -07:00
cleancache.c
compaction.c mm/compaction.c: update comment about zone lock in isolate_freepages_block 2013-11-13 12:09:03 +09:00
debug-pagealloc.c
dmapool.c
fadvise.c
failslab.c
filemap_xip.c
filemap.c mm: memcg: handle non-error OOM situations more gracefully 2013-10-16 21:35:53 -07:00
fremap.c mm: save soft-dirty bits on file pages 2013-08-13 17:57:48 -07:00
frontswap.c
highmem.c
huge_memory.c mm/huge_memory.c: fix stale comments of transparent_hugepage_flags 2013-11-13 12:09:03 +09:00
hugetlb_cgroup.c cgroup: pass around cgroup_subsys_state instead of cgroup in file methods 2013-08-08 20:11:24 -04:00
hugetlb.c mm: hugetlb: initialize PG_reserved for tail pages of gigantic compound pages 2013-10-16 21:35:52 -07:00
hwpoison-inject.c mm/hwpoison: fix the lack of one reference count against poisoned page 2013-09-30 14:31:03 -07:00
init-mm.c
internal.h mm: vmscan: fix do_try_to_free_pages() livelock 2013-09-11 15:58:01 -07:00
interval_tree.c
Kconfig powerpc: Fix memory hotplug with sparse vmemmap 2013-10-03 17:21:38 +10:00
Kconfig.debug
kmemcheck.c
kmemleak-test.c
kmemleak.c mm: replace strict_strtoul() with kstrtoul() 2013-09-11 15:57:11 -07:00
ksm.c ksm: remove redundant __GFP_ZERO from kcalloc 2013-11-13 12:09:02 +09:00
list_lru.c mm: list_lru: fix almost infinite loop causing effective livelock 2013-10-30 12:57:46 -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/hwpoison: fix traversal of hugetlbfs pages to avoid printk flood 2013-09-30 14:31:02 -07:00
Makefile list: add a new LRU list type 2013-09-10 18:56:30 -04:00
memblock.c memblock, numa: binary search node id 2013-09-11 15:57:51 -07:00
memcontrol.c mm: add a helper function to check may oom condition 2013-11-13 12:09:04 +09:00
memory_hotplug.c cpu/mem hotplug: add try_online_node() for cpu_up() 2013-11-13 12:09:04 +09:00
memory-failure.c mm/memory-failure.c: move set_migratetype_isolate() outside get_any_page() 2013-11-13 12:09:04 +09:00
memory.c mm: remove obsolete comments about page table lock 2013-11-13 12:09:03 +09:00
mempolicy.c mm, mempolicy: make mpol_to_str robust and always succeed 2013-11-13 12:09:05 +09:00
mempool.c mm/mempool.c: convert kmalloc_node(...GFP_ZERO...) to kzalloc_node(...) 2013-09-11 15:58:14 -07:00
migrate.c Merge branch 'linus' into sched/core 2013-11-01 08:24:41 +01:00
mincore.c
mlock.c mm/mlock.c: prevent walking off the end of a pagetable in no-pmd configuration 2013-09-30 14:31:02 -07:00
mm_init.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mmap.c mm/mmap: remove unnecessary assignment 2013-09-11 15:58:13 -07:00
mmu_context.c
mmu_notifier.c
mmzone.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mprotect.c Merge branch 'linus' into sched/core 2013-11-01 08:24:41 +01:00
mremap.c mm: revert mremap pud_free anti-fix 2013-10-16 21:35:53 -07:00
msync.c
nobootmem.c mm/nobootmem.c: have __free_pages_memory() free in larger chunks. 2013-11-13 12:09:04 +09:00
nommu.c mm: remove free_area_cache 2013-07-10 18:11:34 -07:00
oom_kill.c mm: memcg: handle non-error OOM situations more gracefully 2013-10-16 21:35:53 -07:00
page_alloc.c mm: add a helper function to check may oom condition 2013-11-13 12:09:04 +09:00
page_cgroup.c
page_io.c aio: Kill aio_rw_vect_retry() 2013-07-30 11:53:12 -04:00
page_isolation.c mm: memory-hotplug: enable memory hotplug to handle hugepage 2013-09-11 15:57:48 -07:00
page-writeback.c writeback: fix negative bdi max pause 2013-10-16 21:35:53 -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: clear memory allocated with the km allocator 2010-09-10 10:56:24 +02:00
percpu-vm.c
percpu.c
pgtable-generic.c mm: move pgtable related functions to right place 2013-09-11 15:57:30 -07:00
process_vm_access.c
quicklist.c
readahead.c mm/readahead.c:do_readhead(): don't check for ->readpage 2013-11-13 12:09:02 +09:00
rmap.c thp: account anon transparent huge pages into NR_ANON_PAGES 2013-09-12 15:38:03 -07:00
shmem.c initmpfs: make rootfs use tmpfs when CONFIG_TMPFS enabled 2013-09-11 15:59:37 -07:00
slab_common.c slab_common: Do not check for duplicate slab names 2013-09-28 09:47:41 +03:00
slab.c
slab.h memcg: check that kmem_cache has memcg_params before accessing it 2013-08-28 19:26:38 -07:00
slob.c mm/sl[aou]b: Move kmallocXXX functions to common code 2013-09-04 20:51:33 +03:00
slub.c Merge branch 'slab/next' of git://git.kernel.org/pub/scm/linux/kernel/git/penberg/linux 2013-09-15 07:15:06 -04:00
sparse-vmemmap.c
sparse.c mm/sparse: introduce alloc_usemap_and_memmap 2013-09-11 15:58:01 -07:00
swap_state.c lib/radix-tree.c: make radix_tree_node_alloc() work correctly within interrupt 2013-09-11 15:59:36 -07:00
swap.c mm: make lru_add_drain_all() selective 2013-09-12 15:38:02 -07:00
swapfile.c swap: fix set_blocksize race during swapon/swapoff 2013-10-16 21:35:53 -07:00
truncate.c truncate: drop 'oldsize' truncate_pagecache() parameter 2013-09-12 15:38:02 -07:00
util.c swap: clean-up #ifdef in page_mapping() 2013-09-11 15:57:31 -07:00
vmalloc.c mm/vmalloc: fix show vmap_area information race with vmap_area tear down 2013-11-13 12:09:05 +09:00
vmpressure.c Merge branch 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup 2013-09-03 18:25:03 -07:00
vmscan.c mm/vmscan.c: don't forget to free shrinker->nr_deferred 2013-10-16 21:35:52 -07:00
vmstat.c mm: vmscan: fix do_try_to_free_pages() livelock 2013-09-11 15:58:01 -07:00
zbud.c mm/zbud: fix some trivial typos in comments 2013-09-11 15:57:35 -07:00
zswap.c mm/zswap: bugfix: memory leak when re-swapon 2013-10-16 21:35:52 -07:00