linux/mm
Tejun Heo 833af8427b percpu: restructure pcpu_extend_area_map() to fix bugs and improve readability
pcpu_extend_area_map() had the following two bugs.

* It should return 1 if pcpu_lock was dropped and reacquired but it
  returned 0.  This could lead to oops if free_percpu() races with
  area map extension.

* pcpu_mem_free() was called under pcpu_lock.  pcpu_mem_free() might
  end up calling vfree() which isn't IRQ safe.  This could lead to
  deadlock through lock order inversion via IRQ.

In addition, Linus pointed out that the temporary lock dropping and
subtle three-way return value of pcpu_extend_area_map() was very ugly
and suggested to split the function into two - pcpu_need_to_extend()
and pcpu_extend_area_map().

This patch restructures pcpu_extend_area_map() as suggested and fixes
the two bugs.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
2009-11-13 00:55:35 +09:00
..
allocpercpu.c percpu: use dynamic percpu allocator as the default percpu allocator 2009-06-24 15:13:35 +09:00
backing-dev.c writeback: splice dirty inode entries to default bdi on bdi_destroy() 2009-09-16 15:18:52 +02:00
bootmem.c kmemleak: Do not report alloc_bootmem blocks as leaks 2009-08-27 14:29:17 +01:00
bounce.c block: remove some includings of blktrace_api.h 2009-06-16 11:19:36 +02:00
debug-pagealloc.c generic debug pagealloc 2009-04-01 08:59:13 -07:00
dmapool.c dmapools: protect page_list walk in show_pools() 2009-06-30 18:56:00 -07:00
fadvise.c readahead: move max_sane_readahead() calls into force_page_cache_readahead() 2009-06-16 19:47:28 -07:00
failslab.c kmemtrace, mm: fix slab.h dependency problem in mm/failslab.c 2009-04-03 12:23:01 +02:00
filemap_xip.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
filemap.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
fremap.c Do not account for the address space used by hugetlbfs using VM_ACCOUNT 2009-02-10 10:48:42 -08:00
highmem.c block: remove some includings of blktrace_api.h 2009-06-16 11:19:36 +02:00
hugetlb.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
hwpoison-inject.c HWPOISON: Add simple debugfs interface to inject hwpoison on arbitary PFNs 2009-09-16 11:50:17 +02:00
init-mm.c mm: consolidate init_mm definition 2009-06-16 19:47:28 -07:00
internal.h mm: move highest_memmap_pfn 2009-09-22 07:17:41 -07:00
Kconfig x86: Fix hwpoison code related build failure on 32-bit NUMAQ 2009-09-27 09:55:11 +02:00
Kconfig.debug trivial: improve help text for mm debug config options 2009-09-21 15:14:57 +02:00
kmemcheck.c kmemcheck: add hooks for the page allocator 2009-06-15 15:48:33 +02:00
kmemleak-test.c percpu: clean up percpu variable definitions 2009-06-24 15:13:48 +09:00
kmemleak.c kmemleak: Improve the "Early log buffer exceeded" error message 2009-09-11 10:42:09 +01:00
ksm.c ksm: change default values to better fit into mainline kernel 2009-09-24 07:20:56 -07:00
maccess.c [S390] maccess: add weak attribute to probe_kernel_write 2009-06-12 10:27:37 +02:00
madvise.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
Makefile procfs: disable per-task stack usage on NOMMU 2009-09-24 17:11:24 -07:00
memcontrol.c memcg: show swap usage in stat file 2009-09-24 07:20:59 -07:00
memory_hotplug.c walk system ram range 2009-09-23 07:39:41 -07:00
memory-failure.c HWPOISON: The high level memory error handler in the VM v7 2009-09-16 11:50:15 +02:00
memory.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2009-09-24 08:32:11 -07:00
mempolicy.c mm: make set_mempolicy(MPOL_INTERLEAV) N_HIGH_MEMORY aware 2009-08-07 10:39:55 -07:00
mempool.c mm: remove broken 'kzalloc' mempool 2009-09-22 07:17:35 -07:00
migrate.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
mincore.c [CVE-2009-0029] System call wrappers part 14 2009-01-14 14:15:24 +01:00
mlock.c mm: m(un)lock avoid ZERO_PAGE 2009-09-22 07:17:40 -07:00
mm_init.c mm: mminit_loglevel cannot be __meminitdata anymore 2008-08-20 15:40:30 -07:00
mmap.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
mmu_context.c mm: reduce atomic use on use_mm fast path 2009-09-22 07:17:42 -07:00
mmu_notifier.c ksm: add mmu_notifier set_pte_at_notify() 2009-09-22 07:17:31 -07:00
mmzone.c [ARM] Double check memmap is actually valid with a memmap has unexpected holes V2 2009-05-18 11:22:24 +01:00
mprotect.c perf: Do the big rename: Performance Counters -> Performance Events 2009-09-21 14:28:04 +02:00
mremap.c truncate: new helpers 2009-09-24 08:41:47 -04:00
msync.c [CVE-2009-0029] System call wrappers part 13 2009-01-14 14:15:23 +01:00
nommu.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
oom_kill.c oom: oom_kill doesn't kill vfork parent (or child) 2009-09-22 07:17:39 -07:00
page_alloc.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
page_cgroup.c memory hotplug: alloc page from other node in memory online 2009-09-22 07:17:26 -07:00
page_io.c mm: remove file argument from swap_readpage() 2009-06-16 19:47:44 -07:00
page_isolation.c memory hotplug: fix page_zone() calculation in test_pages_isolated() 2008-11-06 15:41:19 -08:00
page-writeback.c writeback: pass in super_block to bdi_start_writeback() 2009-09-26 00:10:40 +02:00
pagewalk.c
percpu.c percpu: restructure pcpu_extend_area_map() to fix bugs and improve readability 2009-11-13 00:55:35 +09:00
prio_tree.c
quicklist.c cpumask: use new-style cpumask ops in mm/quicklist. 2009-09-24 09:34:52 +09:30
readahead.c readahead: introduce context readahead algorithm 2009-06-16 19:47:30 -07:00
rmap.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
shmem_acl.c shmfs: use 'check_acl' instead of 'permission' 2009-09-08 11:08:46 -07:00
shmem.c const: mark struct vm_struct_operations 2009-09-27 11:39:25 -07:00
slab.c mm: replace various uses of num_physpages by totalram_pages 2009-09-22 07:17:38 -07:00
slob.c slab: remove duplicate kmem_cache_init_late() declarations 2009-08-06 11:36:25 +03:00
slub.c mm: kmem_cache_create(): make it easier to catch NULL cache names 2009-09-22 07:17:33 -07:00
sparse-vmemmap.c memory hotplug: alloc page from other node in memory online 2009-09-22 07:17:26 -07:00
sparse.c memory hotplug: alloc page from other node in memory online 2009-09-22 07:17:26 -07:00
swap_state.c mm: add_to_swap_cache() does not return -EEXIST 2009-09-22 07:17:35 -07:00
swap.c mm: replace various uses of num_physpages by totalram_pages 2009-09-22 07:17:38 -07:00
swapfile.c Merge branch 'hwpoison' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-mce-2.6 2009-09-24 07:53:22 -07:00
thrash.c mm: pass mm to grab_swap_token 2009-06-23 12:50:05 -07:00
truncate.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 2009-09-24 08:32:11 -07:00
util.c Merge branches 'slab/documentation', 'slab/fixes', 'slob/cleanups' and 'slub/fixes' into for-linus 2009-06-17 08:30:15 +03:00
vmalloc.c kcore: register module area in generic way 2009-09-23 07:39:42 -07:00
vmscan.c Merge branch 'writeback' of git://git.kernel.dk/linux-2.6-block 2009-09-25 09:27:30 -07:00
vmstat.c mm: vmstat: add isolate pages 2009-09-22 07:17:29 -07:00