memcg: keep root group unchanged if creation fails

If the request is to create non-root group and we fail to meet it, we
should leave the root unchanged.

Signed-off-by: Hillf Danton <dhillf@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: potential integer overflow in nilfs_ioctl_clean_segments()

There is a potential integer overflow in nilfs_ioctl_clean_segments().
When a large argv[n].v_nmembs is passed from the userspace, the subsequent
call to vmalloc() will allocate a buffer smaller than expected, which
leads to out-of-bound access in nilfs_ioctl_move_blocks() and
lfs_clean_segments().

The following check does not prevent the overflow because nsegs is also
controlled by the userspace and could be very large.

if (argv[n].v_nmembs > nsegs * nilfs->ns_blocks_per_segment)
goto out_free;

This patch clamps argv[n].v_nmembs to UINT_MAX / argv[n].v_size, and
returns -EINVAL when overflow.

Signed-off-by: Haogang Chen <haogangchen@gmail.com>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

nilfs2: unbreak compat ioctl

commit 828b1c50ae ("nilfs2: add compat ioctl") incidentally broke all
other NILFS compat ioctls.  Make them work again.

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Tested-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: <stable@vger.kernel.org> [3.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

memcg: add mem_cgroup_replace_page_cache() to fix LRU issue

Commit ef6a3c6311 ("mm: add replace_page_cache_page() function") added a
function replace_page_cache_page().  This function replaces a page in the
radix-tree with a new page.  WHen doing this, memory cgroup needs to fix
up the accounting information.  memcg need to check PCG_USED bit etc.

In some(many?) cases, 'newpage' is on LRU before calling
replace_page_cache().  So, memcg's LRU accounting information should be
fixed, too.

This patch adds mem_cgroup_replace_page_cache() and removes the old hooks.
 In that function, old pages will be unaccounted without touching
res_counter and new page will be accounted to the memcg (of old page).
WHen overwriting pc->mem_cgroup of newpage, take zone->lru_lock and avoid
races with LRU handling.

Background:
  replace_page_cache_page() is called by FUSE code in its splice() handling.
  Here, 'newpage' is replacing oldpage but this newpage is not a newly allocated
  page and may be on LRU. LRU mis-accounting will be critical for memory cgroup
  because rmdir() checks the whole LRU is empty and there is no account leak.
  If a page is on the other LRU than it should be, rmdir() will fail.

Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Michal Hocko <mhocko@suse.cz>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cpusets-stall-when-updating-mems_allowed-for-mempolicy-or-disjoint-nodemask-fix-2-fix-2-fix

Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cpusets-stall-when-updating-mems_allowed-for-mempolicy-or-disjoint-nodemask-fix-2-fix-2

Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cpusets-stall-when-updating-mems_allowed-for-mempolicy-or-disjoint-nodemask-fix-2

Here's a cleaner way of doing it, we can extend it to mm/slab.c later.
Please fold into
cpusets-stall-when-updating-mems_allowed-for-mempolicy-or-disjoint-nodemask.patch.

Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cpusets-stall-when-updating-mems_allowed-for-mempolicy-or-disjoint-nodemask-fix

stupid temporary hack to make it build with CONFIG_NUMA=n

Cc: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Miao Xie <miaox@cn.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask

Kernels where MAX_NUMNODES > BITS_PER_LONG may temporarily see an empty
nodemask in a tsk's mempolicy if its previous nodemask is remapped onto a
new set of allowed cpuset nodes where the two nodemasks, as a result of
the remap, are now disjoint.

c0ff7453bb5c ("cpuset,mm: fix no node to alloc memory when changing
cpuset's mems") adds get_mems_allowed() to prevent the set of allowed
nodes from changing for a thread.  This causes any update to a set of
allowed nodes to stall until put_mems_allowed() is called.

This stall is unncessary, however, if at least one node remains unchanged
in the update to the set of allowed nodes.  This was addressed by
89e8a244b97e ("cpusets: avoid looping when storing to mems_allowed if one
node remains set"), but it's still possible that an empty nodemask may be
read from a mempolicy because the old nodemask may be remapped to the new
nodemask during rebind.  To prevent this, only avoid the stall if there is
no mempolicy for the thread being changed.

This is a temporary solution until all reads from mempolicy nodemasks can
be guaranteed to not be empty without the get_mems_allowed()
synchronization.

Also moves the check for nodemask intersection inside task_lock() so that
tsk->mems_allowed cannot change.  This ensures that nothing can set this
tsk's mems_allowed out from under us and also protects tsk->mempolicy.

Reported-by: Miao Xie <miaox@cn.fujitsu.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Paul Menage <paul@paulmenage.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

Merge remote-tracking branch 'uapi/for-next'

Merge remote-tracking branch 'kvmtool/master'

Conflicts:
include/net/9p/9p.h
scripts/kconfig/Makefile

Merge remote-tracking branch 'remoteproc/for-next'

Merge remote-tracking branch 'memblock/memblock-kill-early_node_map'

Conflicts:
arch/arm/mm/init.c
arch/score/Kconfig

Merge remote-tracking branch 'xshm/xshm-for-next'

Merge remote-tracking branch 'kmap_atomic/kmap_atomic'

Conflicts:
Documentation/feature-removal-schedule.txt

Merge remote-tracking branch 'vhost/linux-next'

Conflicts:
arch/hexagon/Kconfig
arch/m68k/Kconfig

Merge remote-tracking branch 'pinctrl/for-next'

Merge remote-tracking branch 'writeback/writeback-for-next'

Merge remote-tracking branch 'tmem/tmem'

Conflicts:
mm/swapfile.c

Merge remote-tracking branch 'char-misc/char-misc-next'

Merge remote-tracking branch 'staging/staging-next'

Conflicts:
drivers/hid/hid-hyperv.c
drivers/staging/hv/Kconfig
drivers/staging/hv/Makefile
drivers/staging/iio/adc/ad799x_core.c

Merge remote-tracking branch 'usb/usb-next'

Merge remote-tracking branch 'tty/tty-next'

Conflicts:
drivers/tty/serial/Kconfig
drivers/tty/serial/Makefile

Merge remote-tracking branch 'driver-core/driver-core-next'

Merge remote-tracking branch 'hsi/for-next'

Merge commit 'refs/next/20111214/regmap'

Conflicts:
drivers/base/regmap/regcache.c
drivers/base/regmap/regmap.c

Merge remote-tracking branch 'namespace/master'

Merge remote-tracking branch 'sysctl/master'

Merge remote-tracking branch 'percpu/for-next'

Merge remote-tracking branch 'xen-two/linux-next'

Conflicts:
arch/x86/xen/Kconfig

Merge remote-tracking branch 'xen/upstream/xen'

Conflicts:
arch/x86/xen/Kconfig

Merge remote-tracking branch 'oprofile/for-next'

Merge remote-tracking branch 'kmemleak/kmemleak'

Merge remote-tracking branch 'cgroup/for-next'

Merge remote-tracking branch 'uprobes/for-next'

Merge remote-tracking branch 'tip/auto-latest'

Conflicts:
drivers/cpufreq/cpufreq_conservative.c
drivers/cpufreq/cpufreq_ondemand.c
drivers/macintosh/rack-meter.c
fs/proc/stat.c
fs/proc/uptime.c
kernel/sched/core.c
kernel/sched/fair.c

Merge remote-tracking branch 'gpio/gpio/next'

Merge remote-tracking branch 'edac-amd/for-next'

Merge remote-tracking branch 'fsnotify/for-next'

Merge remote-tracking branch 'apm/for-next'

Merge remote-tracking branch 'pm/linux-next'

Conflicts:
fs/xfs/xfs_buf.c

Merge remote-tracking branch 'trivial/for-next'

Conflicts:
arch/powerpc/platforms/40x/Kconfig

Merge remote-tracking branch 'osd/linux-next'

Merge remote-tracking branch 'cputime/cputime'

Merge remote-tracking branch 'iommu/next'

Conflicts:
drivers/pci/hotplug/acpiphp_glue.c
include/linux/pci_regs.h

Merge remote-tracking branch 'watchdog/linux-next'

Merge remote-tracking branch 'security/next'

Conflicts:
lib/Makefile

Merge remote-tracking branch 'regulator/for-next'

Merge remote-tracking branch 'fbdev/fbdev-next'

Merge remote-tracking branch 'drm/drm-next'

Conflicts:
drivers/gpu/drm/nouveau/nouveau_sgdma.c

Merge remote-tracking branch 'mfd/for-next'

Merge remote-tracking branch 'md/for-next'

Merge remote-tracking branch 'slab/for-next'

Merge remote-tracking branch 'kgdb/kgdb-next'

Merge remote-tracking branch 'mmc/mmc-next'

Conflicts:
drivers/mmc/card/block.c

Merge remote-tracking branch 'battery/master'

Merge commit 'refs/next/20111215/block'

Merge remote-tracking branch 'input/next'

Conflicts:
drivers/input/keyboard/samsung-keypad.c

Merge branch 'quilt/rr'

Merge remote-tracking branch 'cpufreq/next'

Merge remote-tracking branch 'sound-asoc/for-next'

Merge remote-tracking branch 'sound/for-next'

Conflicts:
arch/arm/mach-s3c64xx/mach-crag6410.c

Merge remote-tracking branch 'crypto/master'

Merge remote-tracking branch 'l2-mtd/master'

Conflicts:
drivers/mtd/maps/bcm963xx-flash.c

Merge remote-tracking branch 'mtd/master'

Merge remote-tracking branch 'bluetooth/master'

Merge remote-tracking branch 'wireless-next/master'

Conflicts:
drivers/net/wireless/iwlwifi/iwl-agn.c

Merge remote-tracking branch 'net-next/master'

Conflicts:
drivers/net/wireless/iwlwifi/iwl-agn.c

Merge remote-tracking branch 'slave-dma/next'

Conflicts:
drivers/dma/pl330.c

Merge remote-tracking branch 'target-merge/for-next-merge'

Merge remote-tracking branch 'target-updates/for-next'

Merge remote-tracking branch 'scsi/master'

Merge remote-tracking branch 'dlm/next'

Merge remote-tracking branch 'ubi/linux-next'

Merge remote-tracking branch 'libata/NEXT'

Merge remote-tracking branch 'kconfig/for-next'

Merge remote-tracking branch 'kbuild/for-next'

Merge remote-tracking branch 'v4l-dvb/master'

Conflicts:
drivers/staging/media/as102/as102_drv.h

Merge remote-tracking branch 'hwmon-staging/hwmon-next'

Merge branch 'quilt/jdelvare-hwmon'

Merge remote-tracking branch 'bjdooks-i2c/next-i2c'

Conflicts:
drivers/i2c/busses/i2c-designware-platdrv.c

Merge branch 'quilt/i2c'

Merge commit 'refs/next/20111216/hid'

Merge remote-tracking branch 'pci/linux-next'

Merge remote-tracking branch 'xfs/master'

Merge remote-tracking branch 'ubifs/linux-next'

Merge remote-tracking branch 'nfsd/nfsd-next'

Merge remote-tracking branch 'nfs/linux-next'

Merge remote-tracking branch 'logfs/master'

Conflicts:
fs/logfs/file.c

Merge remote-tracking branch 'gfs2/master'

Merge remote-tracking branch 'fuse/for-next'

Merge remote-tracking branch 'ecryptfs/next'

Merge remote-tracking branch 'xtensa/master'

Merge remote-tracking branch 's390/features'

Merge remote-tracking branch '52xx-and-virtex/powerpc/next'

Merge remote-tracking branch '4xx/next'

Conflicts:
arch/powerpc/platforms/40x/ppc40x_simple.c

Merge remote-tracking branch 'powerpc/next'

Merge remote-tracking branch 'parisc/for-next'

Merge remote-tracking branch 'mips/mips-for-linux-next'

Conflicts:
arch/mips/kernel/perf_event_mipsxx.c

Merge remote-tracking branch 'm68knommu/for-next'

Conflicts:
arch/m68k/Kconfig.debug