OpenCloudOS-Kernel/mm
Heiko Carstens 167d0f258f mm: take memory hotplug lock within numa_zonelist_order_handler()
Andre Wild reported the following warning:

  WARNING: CPU: 2 PID: 1205 at kernel/cpu.c:240 lockdep_assert_cpus_held+0x4c/0x60
  Modules linked in:
  CPU: 2 PID: 1205 Comm: bash Not tainted 4.13.0-rc2-00022-gfd2b2c57ec20 #10
  Hardware name: IBM 2964 N96 702 (z/VM 6.4.0)
  task: 00000000701d8100 task.stack: 0000000073594000
  Krnl PSW : 0704f00180000000 0000000000145e24 (lockdep_assert_cpus_held+0x4c/0x60)
  ...
  Call Trace:
   lockdep_assert_cpus_held+0x42/0x60)
   stop_machine_cpuslocked+0x62/0xf0
   build_all_zonelists+0x92/0x150
   numa_zonelist_order_handler+0x102/0x150
   proc_sys_call_handler.isra.12+0xda/0x118
   proc_sys_write+0x34/0x48
   __vfs_write+0x3c/0x178
   vfs_write+0xbc/0x1a0
   SyS_write+0x66/0xc0
   system_call+0xc4/0x2b0
   locks held by bash/1205:
   #0:  (sb_writers#4){.+.+.+}, at: vfs_write+0xa6/0x1a0
   #1:  (zl_order_mutex){+.+...}, at: numa_zonelist_order_handler+0x44/0x150
   #2:  (zonelists_mutex){+.+...}, at: numa_zonelist_order_handler+0xf4/0x150
  Last Breaking-Event-Address:
    lockdep_assert_cpus_held+0x48/0x60

This can be easily triggered with e.g.

    echo n > /proc/sys/vm/numa_zonelist_order

In commit 3f906ba236 ("mm/memory-hotplug: switch locking to a percpu
rwsem") memory hotplug locking was changed to fix a potential deadlock.

This also switched the stop_machine() invocation within
build_all_zonelists() to stop_machine_cpuslocked() which now expects
that online cpus are locked when being called.

This assumption is not true if build_all_zonelists() is being called
from numa_zonelist_order_handler().

In order to fix this simply add a mem_hotplug_begin()/mem_hotplug_done()
pair to numa_zonelist_order_handler().

Link: http://lkml.kernel.org/r/20170726111738.38768-1-heiko.carstens@de.ibm.com
Fixes: 3f906ba236 ("mm/memory-hotplug: switch locking to a percpu rwsem")
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Reported-by: Andre Wild <wild@linux.vnet.ibm.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-08-02 17:16:11 -07:00
..
kasan
Kconfig
Kconfig.debug
Makefile
backing-dev.c
balloon_compaction.c
bootmem.c
cleancache.c
cma.c
cma.h
cma_debug.c
compaction.c
debug.c
debug_page_ref.c
dmapool.c
early_ioremap.c
fadvise.c
failslab.c
filemap.c
frame_vector.c
frontswap.c
gup.c
highmem.c
huge_memory.c
hugetlb.c
hugetlb_cgroup.c
hwpoison-inject.c
init-mm.c
internal.h
interval_tree.c
khugepaged.c
kmemcheck.c
kmemleak-test.c
kmemleak.c
ksm.c
list_lru.c
maccess.c
madvise.c
memblock.c
memcontrol.c
memory-failure.c
memory.c
memory_hotplug.c
mempolicy.c
mempool.c
memtest.c
migrate.c
mincore.c
mlock.c
mm_init.c
mmap.c
mmu_context.c
mmu_notifier.c
mmzone.c
mprotect.c
mremap.c
msync.c
nobootmem.c
nommu.c
oom_kill.c
page-writeback.c
page_alloc.c mm: take memory hotplug lock within numa_zonelist_order_handler() 2017-08-02 17:16:11 -07:00
page_counter.c
page_ext.c
page_idle.c
page_io.c
page_isolation.c
page_owner.c
page_poison.c
page_vma_mapped.c
pagewalk.c
percpu-internal.h
percpu-km.c
percpu-stats.c
percpu-vm.c
percpu.c
pgtable-generic.c
process_vm_access.c
quicklist.c
readahead.c
rmap.c
rodata_test.c
shmem.c
slab.c
slab.h
slab_common.c
slob.c
slub.c
sparse-vmemmap.c
sparse.c
swap.c
swap_cgroup.c
swap_slots.c
swap_state.c
swapfile.c
truncate.c
usercopy.c
userfaultfd.c
util.c
vmacache.c
vmalloc.c
vmpressure.c
vmscan.c
vmstat.c
workingset.c
z3fold.c
zbud.c
zpool.c
zsmalloc.c
zswap.c