X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=Documentation%2Fsysctl%2Fkernel.txt;h=a028b92001eddca50be93544c8667bd585417401;hb=8ec006c58775869175edee3d23f4525b6df2935a;hp=b3d8b492274052c8fbb538b1fba96c16a4d64cff;hpb=d19110baaf20d5183689287bdbcf91e26e40cb79;p=pandora-kernel.git

diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index b3d8b4922740..a028b92001ed 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