3 files changed, 72 insertions, 8 deletions

diff --git a/Documentation/sysctl/fs.txt b/Documentation/sysctl/fs.txt
index 1458448436c..62682500878 100644
--- a/Documentation/sysctl/fs.txt
+++ b/Documentation/sysctl/fs.txt
@@ -96,13 +96,16 @@ handles that the Linux kernel will allocate. When you get lots
 of error messages about running out of file handles, you might
 want to increase this limit.
 
-The three values in file-nr denote the number of allocated
-file handles, the number of unused file handles and the maximum
-number of file handles. When the allocated file handles come
-close to the maximum, but the number of unused file handles is
-significantly greater than 0, you've encountered a peak in your 
-usage of file handles and you don't need to increase the maximum.
-
+Historically, the three values in file-nr denoted the number of
+allocated file handles, the number of allocated but unused file
+handles, and the maximum number of file handles. Linux 2.6 always
+reports 0 as the number of free file handles -- this is not an
+error, it just means that the number of allocated file handles
+exactly matches the number of used file handles.
+
+Attempts to allocate more file descriptors than file-max are
+reported with printk, look for "VFS: file-max limit <number>
+reached".
 ==============================================================
 
 nr_open:
diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index b3d8b492274..a028b92001e 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -22,6 +22,7 @@ show up in /proc/sys/kernel:
 - callhome		     [ S390 only ]
 - auto_msgmni
 - core_pattern
+- core_pipe_limit
 - core_uses_pid
 - ctrl-alt-del
 - dentry-state
@@ -135,6 +136,27 @@ core_pattern is used to specify a core dumpfile pattern name.
 
 ==============================================================
 
+core_pipe_limit:
+
+This sysctl is only applicable when core_pattern is configured to pipe core
+files to user space helper a (when the first character of core_pattern is a '|',
+see above).  When collecting cores via a pipe to an application, it is
+occasionally usefull for the collecting application to gather data about the
+crashing process from its /proc/pid directory.  In order to do this safely, the
+kernel must wait for the collecting process to exit, so as not to remove the
+crashing processes proc files prematurely.  This in turn creates the possibility
+that a misbehaving userspace collecting process can block the reaping of a
+crashed process simply by never exiting.  This sysctl defends against that.  It
+defines how many concurrent crashing processes may be piped to user space
+applications in parallel.  If this value is exceeded, then those crashing
+processes above that value are noted via the kernel log and their cores are
+skipped.  0 is a special value, indicating that unlimited processes may be
+captured in parallel, but that no waiting will take place (i.e. the collecting
+process is not guaranteed access to /proc/<crahing pid>/).  This value defaults
+to 0.
+
+==============================================================
+
 core_uses_pid:
 
 The default coredump filename is "core".  By setting
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index e6fb1ec2744..a6e360d2055 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -32,6 +32,8 @@ Currently, these files are in /proc/sys/vm:
 - legacy_va_layout
 - lowmem_reserve_ratio
 - max_map_count
+- memory_failure_early_kill
+- memory_failure_recovery
 - min_free_kbytes
 - min_slab_ratio
 - min_unmapped_ratio
@@ -53,7 +55,6 @@ Currently, these files are in /proc/sys/vm:
 - vfs_cache_pressure
 - zone_reclaim_mode
 
-
 ==============================================================
 
 block_dump
@@ -275,6 +276,44 @@ e.g., up to one or two maps per allocation.
 
 The default value is 65536.
 
+=============================================================
+
+memory_failure_early_kill:
+
+Control how to kill processes when uncorrected memory error (typically
+a 2bit error in a memory module) is detected in the background by hardware
+that cannot be handled by the kernel. In some cases (like the page
+still having a valid copy on disk) the kernel will handle the failure
+transparently without affecting any applications. But if there is
+no other uptodate copy of the data it will kill to prevent any data
+corruptions from propagating.
+
+1: Kill all processes that have the corrupted and not reloadable page mapped
+as soon as the corruption is detected.  Note this is not supported
+for a few types of pages, like kernel internally allocated data or
+the swap cache, but works for the majority of user pages.
+
+0: Only unmap the corrupted page from all processes and only kill a process
+who tries to access it.
+
+The kill is done using a catchable SIGBUS with BUS_MCEERR_AO, so processes can
+handle this if they want to.
+
+This is only active on architectures/platforms with advanced machine
+check handling and depends on the hardware capabilities.
+
+Applications can override this setting individually with the PR_MCE_KILL prctl
+
+==============================================================
+
+memory_failure_recovery
+
+Enable memory failure recovery (when supported by the platform)
+
+1: Attempt recovery.
+
+0: Always panic on a memory failure.
+
 ==============================================================
 
 min_free_kbytes: