linux-toradex.git/mm, branch v4.8-rc2

mm/memory_hotplug.c: initialize per_cpu_nodestats for hotadded pgdats

2016-08-11T23:58:14+00:00

The following oops occurs after a pgdat is hotadded:

  Unable to handle kernel paging request for data at address 0x00c30001
  Faulting instruction address: 0xc00000000022f8f4
  Oops: Kernel access of bad area, sig: 11 [#1]
  SMP NR_CPUS=2048 NUMA pSeries
  Modules linked in: ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 ipt_REJECT nf_reject_ipv4 xt_conntrack ebtable_nat ebtable_broute bridge stp llc ebtable_filter ebtables ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_security ip6table_raw ip6table_filter ip6_tables iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack iptable_mangle iptable_security iptable_raw iptable_filter nls_utf8 isofs sg virtio_balloon uio_pdrv_genirq uio ip_tables xfs libcrc32c sr_mod cdrom sd_mod virtio_net ibmvscsi scsi_transport_srp virtio_pci virtio_ring virtio dm_mirror dm_region_hash dm_log dm_mod
  CPU: 0 PID: 0 Comm: swapper/0 Tainted: G        W 4.8.0-rc1-device #110
  task: c000000000ef3080 task.stack: c000000000f6c000
  NIP: c00000000022f8f4 LR: c00000000022f948 CTR: 0000000000000000
  REGS: c000000000f6fa50 TRAP: 0300   Tainted: G        W (4.8.0-rc1-device)
  MSR: 800000010280b033   CR: 84002028  XER: 20000000
  CFAR: d000000001d2013c DAR: 0000000000c30001 DSISR: 40000000 SOFTE: 0
  NIP refresh_cpu_vm_stats+0x1a4/0x2f0
  LR refresh_cpu_vm_stats+0x1f8/0x2f0
  Call Trace:
    refresh_cpu_vm_stats+0x1f8/0x2f0 (unreliable)

Add per_cpu_nodestats initialization to the hotplug codepath.

Link: http://lkml.kernel.org/r/1470931473-7090-1-git-send-email-arbab@linux.vnet.ibm.com
Signed-off-by: Reza Arbab 
Cc: Mel Gorman 
Cc: Paul Mackerras 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm, oom: fix uninitialized ret in task_will_free_mem()

2016-08-11T23:58:14+00:00

    mm/oom_kill.c: In function `task_will_free_mem':
    mm/oom_kill.c:767: warning: `ret' may be used uninitialized in this function

If __task_will_free_mem() is never called inside the for_each_process()
loop, ret will not be initialized.

Fixes: 1af8bb43269563e4 ("mm, oom: fortify task_will_free_mem()")
Link: http://lkml.kernel.org/r/1470255599-24841-1-git-send-email-geert@linux-m68k.org
Signed-off-by: Geert Uytterhoeven 
Acked-by: Tetsuo Handa 
Acked-by: Michal Hocko 
Cc: Oleg Nesterov 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

kasan: remove the unnecessary WARN_ONCE from quarantine.c

2016-08-11T23:58:14+00:00

It's quite unlikely that the user will so little memory that the per-CPU
quarantines won't fit into the given fraction of the available memory.
Even in that case he won't be able to do anything with the information
given in the warning.

Link: http://lkml.kernel.org/r/1470929182-101413-1-git-send-email-glider@google.com
Signed-off-by: Alexander Potapenko 
Acked-by: Andrey Ryabinin 
Cc: Dmitry Vyukov 
Cc: Andrey Konovalov 
Cc: Christoph Lameter 
Cc: Joonsoo Kim 
Cc: Kuthonuzo Luruo 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: memcontrol: fix memcg id ref counter on swap charge move

2016-08-11T23:58:13+00:00

Since commit 73f576c04b94 ("mm: memcontrol: fix cgroup creation failure
after many small jobs") swap entries do not pin memcg->css.refcnt
directly.  Instead, they pin memcg->id.ref.  So we should adjust the
reference counters accordingly when moving swap charges between cgroups.

Fixes: 73f576c04b941 ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Link: http://lkml.kernel.org/r/9ce297c64954a42dc90b543bc76106c4a94f07e8.1470219853.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov 
Acked-by: Michal Hocko 
Acked-by: Johannes Weiner 
Cc: 	[3.19+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm: memcontrol: fix swap counter leak on swapout from offline cgroup

2016-08-11T23:58:13+00:00

An offline memory cgroup might have anonymous memory or shmem left
charged to it and no swap.  Since only swap entries pin the id of an
offline cgroup, such a cgroup will have no id and so an attempt to
swapout its anon/shmem will not store memory cgroup info in the swap
cgroup map.  As a result, memcg->swap or memcg->memsw will never get
uncharged from it and any of its ascendants.

Fix this by always charging swapout to the first ancestor cgroup that
hasn't released its id yet.

[hannes@cmpxchg.org: add comment to mem_cgroup_swapout]
[vdavydov@virtuozzo.com: use WARN_ON_ONCE() in mem_cgroup_id_get_online()]
  Link: http://lkml.kernel.org/r/20160803123445.GJ13263@esperanza
Fixes: 73f576c04b941 ("mm: memcontrol: fix cgroup creation failure after many small jobs")
Link: http://lkml.kernel.org/r/5336daa5c9a32e776067773d9da655d2dc126491.1470219853.git.vdavydov@virtuozzo.com
Signed-off-by: Vladimir Davydov 
Acked-by: Johannes Weiner 
Acked-by: Michal Hocko 
Cc: 	[3.19+]
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

proc, meminfo: use correct helpers for calculating LRU sizes in meminfo

2016-08-11T23:58:13+00:00

meminfo_proc_show() and si_mem_available() are using the wrong helpers
for calculating the size of the LRUs.  The user-visible impact is that
there appears to be an abnormally high number of unevictable pages.

Link: http://lkml.kernel.org/r/20160805105805.GR2799@techsingularity.net
Signed-off-by: Mel Gorman 
Cc: Dave Chinner 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/hugetlb: fix incorrect hugepages count during mem hotplug

2016-08-11T23:58:13+00:00

When memory hotplug operates, free hugepages will be freed if the
movable node is offline.  Therefore, /proc/sys/vm/nr_hugepages will be
incorrect.

Fix it by reducing max_huge_pages when the node is offlined.

n-horiguchi@ah.jp.nec.com said:

: dissolve_free_huge_page intends to break a hugepage into buddy, and the
: destination hugepage is supposed to be allocated from the pool of the
: destination node, so the system-wide pool size is reduced.  So adding
: h->max_huge_pages-- makes sense to me.

Link: http://lkml.kernel.org/r/1470624546-902-1-git-send-email-zhongjiang@huawei.com
Signed-off-by: zhong jiang 
Cc: Mike Kravetz 
Acked-by: Naoya Horiguchi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/slub.c: run free_partial() outside of the kmem_cache_node->list_lock

2016-08-10T23:40:56+00:00

With debugobjects enabled and using SLAB_DESTROY_BY_RCU, when a
kmem_cache_node is destroyed the call_rcu() may trigger a slab
allocation to fill the debug object pool (__debug_object_init:fill_pool).

Everywhere but during kmem_cache_destroy(), discard_slab() is performed
outside of the kmem_cache_node->list_lock and avoids a lockdep warning
about potential recursion:

  =============================================
  [ INFO: possible recursive locking detected ]
  4.8.0-rc1-gfxbench+ #1 Tainted: G     U
  ---------------------------------------------
  rmmod/8895 is trying to acquire lock:
   (&(&n->list_lock)->rlock){-.-...}, at: [] get_partial_node.isra.63+0x47/0x430

  but task is already holding lock:
   (&(&n->list_lock)->rlock){-.-...}, at: [] __kmem_cache_shutdown+0x54/0x320

  other info that might help us debug this:
  Possible unsafe locking scenario:
        CPU0
        ----
   lock(&(&n->list_lock)->rlock);
   lock(&(&n->list_lock)->rlock);

   *** DEADLOCK ***
   May be due to missing lock nesting notation
   5 locks held by rmmod/8895:
   #0:  (&dev->mutex){......}, at: driver_detach+0x42/0xc0
   #1:  (&dev->mutex){......}, at: driver_detach+0x50/0xc0
   #2:  (cpu_hotplug.dep_map){++++++}, at: get_online_cpus+0x2d/0x80
   #3:  (slab_mutex){+.+.+.}, at: kmem_cache_destroy+0x3c/0x220
   #4:  (&(&n->list_lock)->rlock){-.-...}, at: __kmem_cache_shutdown+0x54/0x320

  stack backtrace:
  CPU: 6 PID: 8895 Comm: rmmod Tainted: G     U          4.8.0-rc1-gfxbench+ #1
  Hardware name: Gigabyte Technology Co., Ltd. H87M-D3H/H87M-D3H, BIOS F11 08/18/2015
  Call Trace:
    __lock_acquire+0x1646/0x1ad0
    lock_acquire+0xb2/0x200
    _raw_spin_lock+0x36/0x50
    get_partial_node.isra.63+0x47/0x430
    ___slab_alloc.constprop.67+0x1a7/0x3b0
    __slab_alloc.isra.64.constprop.66+0x43/0x80
    kmem_cache_alloc+0x236/0x2d0
    __debug_object_init+0x2de/0x400
    debug_object_activate+0x109/0x1e0
    __call_rcu.constprop.63+0x32/0x2f0
    call_rcu+0x12/0x20
    discard_slab+0x3d/0x40
    __kmem_cache_shutdown+0xdb/0x320
    shutdown_cache+0x19/0x60
    kmem_cache_destroy+0x1ae/0x220
    i915_gem_load_cleanup+0x14/0x40 [i915]
    i915_driver_unload+0x151/0x180 [i915]
    i915_pci_remove+0x14/0x20 [i915]
    pci_device_remove+0x34/0xb0
    __device_release_driver+0x95/0x140
    driver_detach+0xb6/0xc0
    bus_remove_driver+0x53/0xd0
    driver_unregister+0x27/0x50
    pci_unregister_driver+0x25/0x70
    i915_exit+0x1a/0x1e2 [i915]
    SyS_delete_module+0x193/0x1f0
    entry_SYSCALL_64_fastpath+0x1c/0xac

Fixes: 52b4b950b507 ("mm: slab: free kmem_cache_node after destroy sysfs file")
Link: http://lkml.kernel.org/r/1470759070-18743-1-git-send-email-chris@chris-wilson.co.uk
Reported-by: Dave Gordon 
Signed-off-by: Chris Wilson 
Reviewed-by: Vladimir Davydov 
Acked-by: Christoph Lameter 
Cc: Pekka Enberg 
Cc: David Rientjes 
Cc: Joonsoo Kim 
Cc: Dmitry Safonov 
Cc: Daniel Vetter 
Cc: Dave Gordon 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

rmap: fix compound check logic in page_remove_file_rmap

2016-08-10T23:40:56+00:00

In page_remove_file_rmap(.) we have the following check:

  VM_BUG_ON_PAGE(compound && !PageTransHuge(page), page);

This is meant to check for either HugeTLB pages or THP when a compound
page is passed in.

Unfortunately, if one disables CONFIG_TRANSPARENT_HUGEPAGE, then
PageTransHuge(.) will always return false, provoking BUGs when one runs
the libhugetlbfs test suite.

This patch replaces PageTransHuge(), with PageHead() which will work for
both HugeTLB and THP.

Fixes: dd78fedde4b9 ("rmap: support file thp")
Link: http://lkml.kernel.org/r/1470838217-5889-1-git-send-email-steve.capper@arm.com
Signed-off-by: Steve Capper 
Acked-by: Kirill A. Shutemov 
Cc: Huang Shijie 
Cc: Will Deacon 
Cc: Catalin Marinas 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm, rmap: fix false positive VM_BUG() in page_add_file_rmap()

2016-08-10T23:40:56+00:00

PageTransCompound() doesn't distinguish THP from from any other type of
compound pages.  This can lead to false-positive VM_BUG_ON() in
page_add_file_rmap() if called on compound page from a driver[1].

I think we can exclude such cases by checking if the page belong to a
mapping.

The VM_BUG_ON_PAGE() is downgraded to VM_WARN_ON_ONCE().  This path
should not cause any harm to non-THP page, but good to know if we step
on anything else.

[1] http://lkml.kernel.org/r/c711e067-0bff-a6cb-3c37-04dfe77d2db1@redhat.com

Link: http://lkml.kernel.org/r/20160810161345.GA67522@black.fi.intel.com
Signed-off-by: Kirill A. Shutemov 
Reported-by: Laura Abbott 
Tested-by: Laura Abbott 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds