5 files changed, 31 insertions, 10 deletions

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.
 
 ==============================================================