percpu: pcpu_embed_first_chunk() should free unused parts after all allocs are complete

pcpu_embed_first_chunk() allocates memory for each node, copies percpu
data and frees unused portions of it before proceeding to the next
group.  This assumes that allocations for different nodes doesn't
overlap; however, depending on memory topology, the bootmem allocator
may end up allocating memory from a different node than the requested
one which may overlap with the portion freed from one of the previous
percpu areas.  This leads to percpu groups for different nodes
overlapping which is a serious bug.

This patch separates out copy & partial free from the allocation loop
such that all allocations are complete before partial frees happen.

This also fixes overlapping frees which could happen on allocation
failure path - out_free_areas path frees whole groups but the groups
could have portions freed at that point.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Reported-by: "Pavel V. Panteleev" <pp_84@mail.ru>
Tested-by: "Pavel V. Panteleev" <pp_84@mail.ru>
LKML-Reference: <E1SNhwY-0007ui-V7.pp_84-mail-ru@f220.mail.ru>
kmemleak: Fix the kmemleak tracking of the percpu areas with !SMP

Kmemleak tracks the percpu allocations via a specific API and the
originally allocated areas must be removed from kmemleak (via
kmemleak_free). The code was already doing this for SMP systems.

Reported-by: Sami Liedes <sami.liedes@iki.fi>
Cc: Tejun Heo <tj@kernel.org>
Cc: Christoph Lameter <cl@linux-foundation.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
cifs: fix revalidation test in cifs_llseek()

This test is always true so it means we revalidate the length every
time, which generates more network traffic.  When it is SEEK_SET or
SEEK_CUR, then we don't need to revalidate.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
sparc64: Do not clobber %g2 in xcall_fetch_glob_regs().

%g2 is meant to hold the CPUID number throughout this routine, since
at the very beginning, and at the very end, we use %g2 to calculate
indexes into per-cpu arrays.

However we erroneously clobber it in order to hold the %cwp register
value mid-stream.

Fix this code to use %g3 for the %cwp read and related calulcations
instead.

Reported-by: Meelis Roos <mroos@linux.ee>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge git://git.samba.org/sfrench/cifs-2.6

Pull cifs fix from Steve French.

* git://git.samba.org/sfrench/cifs-2.6:
  cifs: fix revalidation test in cifs_llseek()
Merge branch 'for-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

Pull percpu fixes from Tejun Heo:
 "This pull request contains two patches.  One is kmemleak annotation
  fix which isn't critical.  The other is kinda serious.

  Depending on NUMA topology, percpu allocator may end up assigning
  overlapping regions for the static percpu areas for different CPUs.
  While critical, the bug has been there for a very long time and only
  few configurations seem to be affected (NUMA configurations w/ no
  memory nodes for example) - so, while it's critical, it isn't exactly
  urgent."

* 'for-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  kmemleak: Fix the kmemleak tracking of the percpu areas with !SMP
  percpu: pcpu_embed_first_chunk() should free unused parts after all allocs are complete
proc/pid/pagemap: correctly report non-present ptes and holes between vmas

Reset the current pagemap-entry if the current pte isn't present, or if
current vma is over.  Otherwise pagemap reports last entry again and
again.

Non-present pte reporting was broken in commit 092b50bacd1c ("pagemap:
introduce data structure for pagemap entry")

Reporting for holes was broken in commit 5aaabe831eb5 ("pagemap: avoid
splitting thp when reading /proc/pid/pagemap")

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Reported-by: Pavel Emelyanov <xemul@parallels.com>
Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: fix division by 0 in percpu_pagelist_fraction()

percpu_pagelist_fraction_sysctl_handler() has only considered -EINVAL as
a possible error from proc_dointvec_minmax().

If any other error is returned, it would proceed to divide by zero since
percpu_pagelist_fraction wasn't getting initialized at any point.  For
example, writing 0 bytes into the proc file would trigger the issue.

Signed-off-by: Sasha Levin <levinsasha928@gmail.com>
Reviewed-by: Minchan Kim <minchan@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hugetlb: prevent BUG_ON in hugetlb_fault() -> hugetlb_cow()

Commit 66aebce747eaf ("hugetlb: fix race condition in hugetlb_fault()")
added code to avoid a race condition by elevating the page refcount in
hugetlb_fault() while calling hugetlb_cow().

However, one code path in hugetlb_cow() includes an assertion that the
page count is 1, whereas it may now also have the value 2 in this path.

The consensus is that this BUG_ON has served its purpose, so rather than
extending it to cover both cases, we just remove it.

Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Acked-by: Mel Gorman <mel@csn.ul.ie>
Acked-by: Hillf Danton <dhillf@gmail.com>
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.cz>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: <stable@vger.kernel.org>	[3.0.29+, 3.2.16+, 3.3.3+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
namespaces, pid_ns: fix leakage on fork() failure

Fork() failure post namespace creation for a child cloned with
CLONE_NEWPID leaks pid_namespace/mnt_cache due to proc being mounted
during creation, but not unmounted during cleanup.  Call
pid_ns_release_proc() during cleanup.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Louis Rilling <louis.rilling@kerlabs.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
memcg: free spare array to avoid memory leak

When the last event is unregistered, there is no need to keep the spare
array anymore.  So free it to avoid memory leak.

Signed-off-by: Sha Zhengju <handai.szj@taobao.com>
Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Reviewed-by: Kirill A. Shutemov <kirill@shutemov.name>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/leds: correct __devexit annotations

__devexit functions are discarded without CONFIG_HOTPLUG, so they need
to be referenced carefully.  A __devexit function may also not be called
from a __devinit function.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Bryan Wu <bryan.wu@canonical.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
mm: nobootmem: fix sign extend problem in __free_pages_memory()

Systems with 8 TBytes of memory or greater can hit a problem where only
the the first 8 TB of memory shows up.  This is due to "int i" being
smaller than "unsigned long start_aligned", causing the high bits to be
dropped.

The fix is to change `i' to unsigned long to match start_aligned
and end_aligned.

Thanks to Jack Steiner for assistance tracking this down.

Signed-off-by: Russ Anderson <rja@sgi.com>
Cc: Jack Steiner <steiner@sgi.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: David S. Miller <davem@davemloft.net>
Cc: Yinghai Lu <yinghai@kernel.org>
Cc: Gavin Shan <shangw@linux.vnet.ibm.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
MAINTAINERS: add maintainer for LED subsystem

Add Bryan Wu as the primary maintainer for drivers/leds

Signed-off-by: Bryan Wu <bryan.wu@canonical.com>
Acked-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc

Pull a sparc fix from David Miller.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc:
  sparc64: Do not clobber %g2 in xcall_fetch_glob_regs().
parisc: add missing includes in asm/spinlock.h

This leads to this errors:

In file included from arch/parisc/include/asm/atomic.h:20:0,
                 from include/linux/atomic.h:4,
                 from arch/parisc/include/asm/bitops.h:56,
                 from include/linux/bitops.h:22,
                 from include/linux/kernel.h:19,
                 from include/linux/sched.h:55,
                 from arch/parisc/kernel/asm-offsets.c:31:
arch/parisc/include/asm/spinlock.h: In function ‘arch_spin_is_locked’:
arch/parisc/include/asm/spinlock.h:9:2: error: implicit declaration of function ‘__ldcw_align’ [-Werror=implicit-function-declaration]
arch/parisc/include/asm/spinlock.h:9:29: warning: initialization makes pointer from integer without a cast [enabled by default]
arch/parisc/include/asm/spinlock.h: In function ‘arch_spin_lock_flags’:
arch/parisc/include/asm/spinlock.h:22:2: error: implicit declaration of function ‘mb’ [-Werror=implicit-function-declaration]
arch/parisc/include/asm/spinlock.h:23:4: warning: assignment makes pointer from integer without a cast [enabled by default]
arch/parisc/include/asm/spinlock.h:24:2: error: implicit declaration of function ‘__ldcw’ [-Werror=implicit-function-declaration]

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parisc: add missing forward declarations in asm/hardware.h

Fixes this warnings:

In file included from arch/parisc/include/asm/processor.h:15:0,
                 from arch/parisc/include/asm/spinlock.h:4,
                 from arch/parisc/include/asm/atomic.h:20,
                 from include/linux/atomic.h:4,
                 from arch/parisc/include/asm/bitops.h:11,
                 from include/linux/bitops.h:22,
                 from include/linux/kernel.h:19,
                 from include/linux/sched.h:55,
                 from arch/parisc/kernel/asm-offsets.c:31:
arch/parisc/include/asm/hardware.h:106:10: warning: ‘struct hardware_path’ declared inside parameter list [enabled by default]
arch/parisc/include/asm/hardware.h:106:10: warning: its scope is only this definition or declaration, which is probably not what you want [enabled by default]
arch/parisc/include/asm/hardware.h:116:59: warning: ‘struct hardware_path’ declared inside parameter list [enabled by default]
arch/parisc/include/asm/hardware.h:118:47: warning: ‘struct hardware_path’ declared inside parameter list [enabled by default]
arch/parisc/include/asm/hardware.h:119:57: warning: ‘struct hardware_path’ declared inside parameter list [enabled by default]

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parisc: drop include of asm/pdc.h from asm/hardware.h

It seems none of the symbols defined by pdc.h is needed, but it introduces an
include loop causing compile errors:

In file included from arch/parisc/include/asm/spinlock.h:4:0,
                 from arch/parisc/include/asm/atomic.h:20,
                 from include/linux/atomic.h:4,
                 from arch/parisc/include/asm/bitops.h:56,
                 from include/linux/bitops.h:35,
                 from include/asm-generic/getorder.h:7,
                 from arch/parisc/include/asm/page.h:162,
                 from arch/parisc/include/asm/pdc.h:346,
                 from arch/parisc/include/asm/hardware.h:5,
                 from arch/parisc/kernel/hardware.c:30:
arch/parisc/include/asm/processor.h:74:16: error: field ‘cpu_type’ has incomplete type
arch/parisc/include/asm/processor.h:77:20: error: field ‘model’ has incomplete type
arch/parisc/include/asm/processor.h: In function ‘parisc_requires_coherency’:
arch/parisc/include/asm/processor.h:349:36: error: ‘mako’ undeclared (first use in this function)
arch/parisc/include/asm/processor.h:349:36: note: each undeclared identifier is reported only once for each function it appears in
arch/parisc/include/asm/processor.h:350:30: error: ‘mako2’ undeclared (first use in this function)

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Acked-by: Grant Grundler <grantgrundler@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parisc: add missing include of asm/page.h to asm/pgtable.h

Fixes these errors:

In file included from arch/parisc/include/asm/io.h:5:0,
                 from include/linux/io.h:22,
                 from include/linux/pci.h:54,
                 from arch/parisc/kernel/setup.c:35:
arch/parisc/include/asm/pgtable.h:92:6: warning: "PAGE_SHIFT" is not defined [-Wundef]
arch/parisc/include/asm/pgtable.h:92:6: warning: "PAGE_SHIFT" is not defined [-Wundef]
arch/parisc/include/asm/pgtable.h:92:6: warning: "BITS_PER_PTE_ENTRY" is not defined [-Wundef]

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
parisc: move definition of PAGE0 to asm/page.h

This was defined in asm/pdc.h which needs to include asm/page.h for
__PAGE_OFFSET. This leads to an include loop so that page.h eventually will
include pdc.h again. While this is no problem because of header guards, it is
a problem because some symbols may be undefined. Such an error is this:

In file included from include/linux/bitops.h:35:0,
                 from include/asm-generic/getorder.h:7,
                 from arch/parisc/include/asm/page.h:162,
                 from arch/parisc/include/asm/pdc.h:346,
                 from arch/parisc/include/asm/processor.h:16,
                 from arch/parisc/include/asm/spinlock.h:6,
                 from arch/parisc/include/asm/atomic.h:20,
                 from include/linux/atomic.h:4,
                 from include/linux/sysfs.h:20,
                 from include/linux/kobject.h:21,
                 from include/linux/device.h:17,
                 from include/linux/eisa.h:5,
                 from arch/parisc/kernel/pci.c:11:
arch/parisc/include/asm/bitops.h: In function ‘set_bit’:
arch/parisc/include/asm/bitops.h:82:2: error: implicit declaration of function ‘_atomic_spin_lock_irqsave’ [-Werror=implicit-function-declaration]
arch/parisc/include/asm/bitops.h:84:2: error: implicit declaration of function ‘_atomic_spin_unlock_irqrestore’ [-Werror=implicit-function-declaration]

Signed-off-by: Rolf Eike Beer <eike-kernel@sf-tec.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>