Merge branch 'akpm' (patches from Andrew Morton)

Merge fixes from Andrew Morton:
 "The nmi patch and watchdog patch aren't actually fixes - they're
  features which needed a few last-minutes touchups.

  Otherwise, a rather large batch of fixes - ocfs2 review takes a while
  and I got distracted and missed last week's batch"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (31 commits)
  ocfs2/dlm: do not purge lockres that is queued for assert master
  ocfs2: do not return DLM_MIGRATE_RESPONSE_MASTERY_REF to avoid endless,loop during umount
  ocfs2: manually do the iput once ocfs2_add_entry failed in ocfs2_symlink and ocfs2_mknod
  ocfs2: fix a tiny race when running dirop_fileop_racer
  ocfs2/dlm: fix misuse of list_move_tail() in dlm_run_purge_list()
  ocfs2: refcount: take rw_lock in ocfs2_reflink
  ocfs2: revert "ocfs2: fix NULL pointer dereference when dismount and ocfs2rec simultaneously"
  ocfs2: fix deadlock when two nodes are converting same lock from PR to EX and idletimeout closes conn
  ocfs2: should add inode into orphan dir after updating entry in ocfs2_rename()
  mm: fix crashes from mbind() merging vmas
  checkpatch: reduce false positives when checking void function return statements
  ia64: arch/ia64/include/uapi/asm/fcntl.h needs personality.h
  DMA, CMA: fix possible memory leak
  slab: fix oops when reading /proc/slab_allocators
  shmem: fix faulting into a hole while it's punched
  mm: let mm_find_pmd fix buggy race with THP fault
  mm: thp: fix DEBUG_PAGEALLOC oops in copy_page_rep()
  kernel/watchdog.c: print traces for all cpus on lockup detection
  nmi: provide the option to issue an NMI back trace to every cpu but current
  Documentation/accounting/getdelays.c: add missing null-terminate after strncpy call
  ...

41 files changed, 703 insertions, 189 deletions

diff --git a/CREDITS b/CREDITS
index c322dcfb926d..28ee1514b9de 100644
--- a/CREDITS
+++ b/CREDITS
@@ -9,6 +9,10 @@
                         Linus
 ----------
 
+M: Matt Mackal
+E: mpm@selenic.com
+D: SLOB slab allocator
+
 N: Matti Aarnio
 E: mea@nic.funet.fi
 D: Alpha systems hacking, IPv6 and other network related stuff
diff --git a/Documentation/accounting/getdelays.c b/Documentation/accounting/getdelays.c
index c6a06b71594d..f40578026a04 100644
--- a/Documentation/accounting/getdelays.c
+++ b/Documentation/accounting/getdelays.c
@@ -314,6 +314,7 @@ int main(int argc, char *argv[])
                         break;
                 case 'm':
                         strncpy(cpumask, optarg, sizeof(cpumask));
+                        cpumask[sizeof(cpumask) - 1] = '\0';
                         maskset = 1;
                         printf("cpumask %s maskset %d\n", cpumask, maskset);
                         break;
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 884904975d0b..c1b9aa8c5a52 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -3130,6 +3130,11 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
                         [KNL] Should the soft-lockup detector generate panics.
                         Format: <integer>
 
+        softlockup_all_cpu_backtrace=
+                        [KNL] Should the soft-lockup detector generate
+                        backtraces on all cpus.
+                        Format: <integer>
+
         sonypi.*=       [HW] Sony Programmable I/O Control Device driver
                         See Documentation/laptops/sonypi.txt
 
diff --git a/Documentation/memory-hotplug.txt b/Documentation/memory-hotplug.txt
index f304edb8fbe7..45134dc23854 100644
--- a/Documentation/memory-hotplug.txt
+++ b/Documentation/memory-hotplug.txt
@@ -209,15 +209,12 @@ If memory device is found, memory hotplug code will be called.
 
 4.2 Notify memory hot-add event by hand
 ------------
-On powerpc, the firmware does not notify a memory hotplug event to the kernel.
-Therefore, "probe" interface is supported to notify the event to the kernel.
-This interface depends on CONFIG_ARCH_MEMORY_PROBE.
-
-CONFIG_ARCH_MEMORY_PROBE is supported on powerpc only. On x86, this config
-option is disabled by default since ACPI notifies a memory hotplug event to
-the kernel, which performs its hotplug operation as the result. Please
-enable this option if you need the "probe" interface for testing purposes
-on x86.
+On some architectures, the firmware may not notify the kernel of a memory
+hotplug event.  Therefore, the memory "probe" interface is supported to
+explicitly notify the kernel.  This interface depends on
+CONFIG_ARCH_MEMORY_PROBE and can be configured on powerpc, sh, and x86
+if hotplug is supported, although for x86 this should be handled by ACPI
+notification.
 
 Probe interface is located at
 /sys/devices/system/memory/probe
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 708bb7f1b7e0..c14374e71775 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -75,6 +75,7 @@ show up in /proc/sys/kernel:
 - shmall
 - shmmax                      [ sysv ipc ]
 - shmmni
+- softlockup_all_cpu_backtrace
 - stop-a                      [ SPARC only ]
 - sysrq                       ==> Documentation/sysrq.txt
 - sysctl_writes_strict
@@ -783,6 +784,22 @@ via the /proc/sys interface:
 
 ==============================================================
 
+softlockup_all_cpu_backtrace:
+
+This value controls the soft lockup detector thread's behavior
+when a soft lockup condition is detected as to whether or not
+to gather further debug information. If enabled, each cpu will
+be issued an NMI and instructed to capture stack trace.
+
+This feature is only applicable for architectures which support
+NMI.
+
+0: do nothing. This is the default behavior.
+
+1: on detection capture more debug information.
+
+==============================================================
+
 tainted:
 
 Non-zero if the kernel has been tainted.  Numeric values, which
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index bd4b34c03738..4415aa915681 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -702,7 +702,8 @@ The batch value of each per cpu pagelist is also updated as a result.  It is
 set to pcp->high/4.  The upper limit of batch is (PAGE_SHIFT * 8)
 
 The initial value is zero.  Kernel does not use this value at boot time to set
-the high water marks for each per cpu page list.
+the high water marks for each per cpu page list.  If the user writes '0' to this
+sysctl, it will revert to this default behavior.
 
 ==============================================================
 
diff --git a/MAINTAINERS b/MAINTAINERS
index 3f2e171047b9..3cc94fff780f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8196,13 +8196,15 @@ S:	Maintained