1 files changed, 16 insertions, 0 deletions

diff --git a/Documentation/sysctl/kernel.txt b/Documentation/sysctl/kernel.txt
index 322a00bb99d9..2dbff53369d0 100644
--- a/Documentation/sysctl/kernel.txt
+++ b/Documentation/sysctl/kernel.txt
@@ -19,6 +19,7 @@ Currently, these files might (depending on your configuration)
 show up in /proc/sys/kernel:
 - acpi_video_flags
 - acct
+- callhome                   [ S390 only ]
 - auto_msgmni
 - core_pattern
 - core_uses_pid
@@ -91,6 +92,21 @@ valid for 30 seconds.
 
 ==============================================================
 
+callhome:
+
+Controls the kernel's callhome behavior in case of a kernel panic.
+
+The s390 hardware allows an operating system to send a notification
+to a service organization (callhome) in case of an operating system panic.
+
+When the value in this file is 0 (which is the default behavior)
+nothing happens in case of a kernel panic. If this value is set to "1"
+the complete kernel oops message is send to the IBM customer service
+organization in case the mainframe the Linux operating system is running
+on has a service contract with IBM.
+
+==============================================================
+
 core_pattern:
 
 core_pattern is used to specify a core dumpfile pattern name.