The race is calling cgroup_clone() while umounting the ns cgroup subsys,
and thus cgroup_clone() might access invalid cgroup_fs, or kill_sb() is
called after cgroup_clone() created a new dir in it.

The BUG I triggered is BUG_ON(root->number_of_cgroups != 1);

  ------------[ cut here ]------------
  kernel BUG at kernel/cgroup.c:1093!
  invalid opcode: 0000 [#1] SMP
  ...
  Process umount (pid: 5177, ti=e411e000 task=e40c4670 task.ti=e411e000)
  ...
  Call Trace:
   [<c0493df7>] ? deactivate_super+0x3f/0x51
   [<c04a3600>] ? mntput_no_expire+0xb3/0xdd
   [<c04a3ab2>] ? sys_umount+0x265/0x2ac
   [<c04a3b06>] ? sys_oldumount+0xd/0xf
   [<c0403911>] ? sysenter_do_call+0x12/0x31
  ...
  EIP: [<c0456e76>] cgroup_kill_sb+0x23/0xe0 SS:ESP 0068:e411ef2c
  ---[ end trace c766c1be3bf944ac ]---

Cc: Serge E. Hallyn <serue@us.ibm.com>
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Paul Menage <menage@google.com>
Cc: "Serge E. Hallyn" <serue@us.ibm.com>
Cc: Balbir Singh <balbir@in.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'cpus4096-for-linus-3' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (77 commits)
  x86: setup_per_cpu_areas() cleanup
  cpumask: fix compile error when CONFIG_NR_CPUS is not defined
  cpumask: use alloc_cpumask_var_node where appropriate
  cpumask: convert shared_cpu_map in acpi_processor* structs to cpumask_var_t
  x86: use cpumask_var_t in acpi/boot.c
  x86: cleanup some remaining usages of NR_CPUS where s/b nr_cpu_ids
  sched: put back some stack hog changes that were undone in kernel/sched.c
  x86: enable cpus display of kernel_max and offlined cpus
  ia64: cpumask fix for is_affinity_mask_valid()
  cpumask: convert RCU implementations, fix
  xtensa: define __fls
  mn10300: define __fls
  m32r: define __fls
  h8300: define __fls
  frv: define __fls
  cris: define __fls
  cpumask: CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
  cpumask: zero extra bits in alloc_cpumask_var_node
  cpumask: replace for_each_cpu_mask_nr with for_each_cpu in kernel/time/
  cpumask: convert mm/
  ...

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/linux-2.6-iommu: (89 commits)
  AMD IOMMU: remove now unnecessary #ifdefs
  AMD IOMMU: prealloc_protection_domains should be static
  kvm/iommu: fix compile warning
  AMD IOMMU: add statistics about total number of map requests
  AMD IOMMU: add statistics about allocated io memory
  AMD IOMMU: add stats counter for domain tlb flushes
  AMD IOMMU: add stats counter for single iommu domain tlb flushes
  AMD IOMMU: add stats counter for cross-page request
  AMD IOMMU: add stats counter for free_coherent requests
  AMD IOMMU: add stats counter for alloc_coherent requests
  AMD IOMMU: add stats counter for unmap_sg requests
  AMD IOMMU: add stats counter for map_sg requests
  AMD IOMMU: add stats counter for unmap_single requests
  AMD IOMMU: add stats counter for map_single requests
  AMD IOMMU: add stats counter for completion wait events
  AMD IOMMU: add init code for statistic collection
  AMD IOMMU: add necessary header defines for stats counting
  AMD IOMMU: add Kconfig entry for statistic collection code
  AMD IOMMU: use dev_name in iommu_enable function
  AMD IOMMU: use calc_devid in prealloc_protection_domains
  ...

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: (34 commits)
  V4L/DVB (10173): Missing v4l2_prio_close in radio_release
  V4L/DVB (10172): add DVB_DEVICE_TYPE= to uevent
  V4L/DVB (10171): Use usb_set_intfdata
  V4L/DVB (10170): tuner-simple: prevent possible OOPS caused by divide by zero error
  V4L/DVB (10168): sms1xxx: fix inverted gpio for lna control on tiger r2
  V4L/DVB (10167): sms1xxx: add support for inverted gpio
  V4L/DVB (10166): dvb frontend: stop using non-C99 compliant comments
  V4L/DVB (10165): Add FE_CAN_2G_MODULATION flag to frontends that support DVB-S2
  V4L/DVB (10164): Add missing S2 caps flag to S2API
  V4L/DVB (10163): em28xx: allocate adev together with struct em28xx dev
  V4L/DVB (10162): tuner-simple: Fix tuner type set message
  V4L/DVB (10161): saa7134: fix autodetection for AVer TV GO 007 FM Plus
  V4L/DVB (10160): em28xx: update chip id for em2710
  V4L/DVB (10157): Add USB ID for the Sil4701 radio from DealExtreme
  V4L/DVB (10156): saa7134: Add support for Avermedia AVer TV GO 007 FM Plus
  V4L/DVB (10155): Add TEA5764 radio driver
  V4L/DVB (10154): saa7134: fix a merge conflict on Behold H6 board
  V4L/DVB (10153): Add the Beholder H6 card to DVB-T part of sources.
  V4L/DVB (10152): Change configuration of the Beholder H6 card
  V4L/DVB (10151): Fix I2C bridge error in zl10353
  ...

those two functions only used in that C file
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/drzeus/mmc:
  mmc: warn about voltage mismatches
  mmc_spi: Add support for OpenFirmware bindings
  pxamci: fix dma_unmap_sg length
  mmc_block: ensure all sectors that do not have errors are read
  drivers/mmc: Move a dereference below a NULL test
  sdhci: handle built-in sdhci with modular leds class
  mmc: balanc pci_iomap with pci_iounmap
  mmc_block: print better error messages
  mmc: Add mmc_vddrange_to_ocrmask() helper function
  ricoh_mmc: Handle newer models of Ricoh controllers
  mmc: Add 8-bit bus width support
  sdhci: activate led support also when module
  mmc: trivial annotation of 'blocks'
  pci: use pci_ioremap_bar() in drivers/mmc
  sdricoh_cs: Add support for Bay Controller devices
  mmc: at91_mci: reorder timer setup and mmc_add_host() call

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  [WATCHDOG] Add support for the WM8350 watchdog
  [WATCHDOG] Add SMSC SCH311x Watchdog Timer.
  [WATCHDOG] ib700wdt - add timeout parameter

* 'cputime' of git://git390.osdl.marist.edu/pub/scm/linux-2.6:
  [PATCH] fast vdso implementation for CLOCK_THREAD_CPUTIME_ID
  [PATCH] improve idle cputime accounting
  [PATCH] improve precision of idle time detection.
  [PATCH] improve precision of process accounting.
  [PATCH] idle cputime accounting
  [PATCH] fix scaled & unscaled cputime accounting

Before, when we only ever printed out the pointer value itself, a NULL
pointer would never cause issues and might as well be printed out as
just its numeric value.

However, with the extended %p formats, especially %pR, we might validly
want to print out resources for debugging.  And sometimes they don't
even exist, and the resource pointer is just NULL.  Print it out as
such, rather than oopsing.

This is a more generic version of a patch done by Trent Piepho (catching
all %p cases rather than just %pR, and using "(null)" instead of
"[NULL]" to match glibc).
Requested-by: Trent Piepho <xyzzy@speakeasy.org>
Acked-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

... just make it a binfmt handler like #! one.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

They are actually alpha vs.  i386/arm/m68k i.e. ecoff vs. aout.

In the only place where we actually tried to handle arm and i386/m68k in
different ways (START_DATA() in coredump handling), the arm variant
works for all of them (i386 and m68k have u.start_code set to 0).
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

it's been used only in sunos compat
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This updates some personal info in the CREDITS file.

I'm no longer actively involved in Keyspan driver work so shouldn't
really be listed as a Maintainer here.

I do however field the occasional question on them and as I'm dropping
the misc.nu domain, want to ensure people can find me should they need
to.
Signed-off-by: Hugh Blemings <hugh@blemings.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Impact: cleanup

__alloc_bootmem and __alloc_bootmem_node do panic
for us in case of fail so no need for additional
checks here.

Also lets use pr_*() macros for printing.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

CONFIG_NR_CPUS will be defined for all arch's whether SMP or not, but
it may not have made it into all arches yet.
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: Reduce inter-node memory traffic.

Reduces inter-node memory traffic (offloading the global system bus)
by allocating referenced struct cpumasks on the same node as the
referring struct.
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: Reduce memory usage, use new API.

This is part of an effort to reduce structure sizes for machines
configured with large NR_CPUS.  cpumask_t gets replaced by
cpumask_var_t, which is either struct cpumask[1] (small NR_CPUS) or
struct cpumask * (large NR_CPUS).

(Changes to powernow-k* by <travis>.)
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: reduce stack size, use new API.

Replace cpumask_t with cpumask_var_t.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Mike Travis <travis@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: Reduce future system panics due to cpumask operations using NR_CPUS

Insure that code does not look at bits >= nr_cpu_ids as when cpumasks are
allocated based on nr_cpu_ids, these extra bits will not be defined.

Also some other minor updates:

   * change in to use cpu accessor function set_cpu_present() instead of
     directly accessing cpu_present_map w/cpu_clear() [arch/x86/kernel/reboot.c]

   * use cpumask_of() instead of &cpumask_of_cpu() [arch/x86/kernel/reboot.c]

   * optimize some cpu_mask_to_apicid_and functions.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: prevents panic from stack overflow on numa-capable machines.

Some of the "removal of stack hogs" changes in kernel/sched.c by using
node_to_cpumask_ptr were undone by the early cpumask API updates, and
causes a panic due to stack overflow.  This patch undoes those changes
by using cpumask_of_node() which returns a 'const struct cpumask *'.

In addition, cpu_coregoup_map is replaced with cpu_coregroup_mask further
reducing stack usage.  (Both of these updates removed 9 FIXME's!)

Also:
   Pick up some remaining changes from the old 'cpumask_t' functions to
   the new 'struct cpumask *' functions.

   Optimize memory traffic by allocating each percpu local_cpu_mask on the
   same node as the referring cpu.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: enables /sys/devices/system/cpu/{kernel_max,offline} user interface

By setting total_cpus, the drivers/base/cpu.c will display the
values of kernel_max (NR_CPUS-1) and the offlined cpu map.
Signed-off-by: Mike Travis <travis@sgi.com>
Acked-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: build fix on ia64

ia64's default_affinity_write() still had old cpumask_t usage:

 /home/mingo/tip/kernel/irq/proc.c: In function `default_affinity_write':
 /home/mingo/tip/kernel/irq/proc.c:114: error: incompatible type for argument 1 of `is_affinity_mask_valid'
 make[3]: *** [kernel/irq/proc.o] Error 1
 make[3]: *** Waiting for unfinished jobs....

update it to cpumask_var_t.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Impact: cleanup

This warning:

 kernel/rcuclassic.c: In function ‘rcu_start_batch’:
 kernel/rcuclassic.c:397: warning: passing argument 1 of ‘cpumask_andnot’ from incompatible pointer type

triggers because one usage site of rcp->cpumask was not converted
to to_cpumask(rcp->cpumask). There's no ill effects of this bug.
Signed-off-by: Ingo Molnar <mingo@elte.hu>

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into cpus4096-v2

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux-2.6-cpumask into merge-rr-cpumask

Conflicts:
	arch/x86/kernel/io_apic.c
	kernel/rcuclassic.c
	kernel/sched.c
	kernel/time/tick-sched.c
Signed-off-by: Mike Travis <travis@sgi.com>
[ mingo@elte.hu: backmerged typo fix for io_apic.c ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>

The #ifdef's are no longer necessary when the iommu-api and the amd
iommu updates are merged together.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: cleanup, reduce kernel size a bit, avoid sparse warning

Fixes sparse warning:
arch/x86/kernel/amd_iommu.c:1299:6: warning: symbol 'prealloc_protection_domains' was not declared. Should it be static?
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

This fixes a compile warning about a variable thats maybe used
uninitialized in the function.
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see total number of map requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see amount of allocated io memory in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of domain tlb flushes in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of single iommu domain tlb flushes in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of requests for more than one page in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of free_coherent requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of alloc_coherent requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of unmap_sg requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of map_sg requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of unmap_single requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

Impact: see number of map_single requests in debugfs
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>