[PATCH] debug: add sysrq_always_enabled boot option

Most distributions enable sysrq support but set it to 0 by default.  Add a
sysrq_always_enabled boot option to always-enable sysrq keys.  Useful for
debugging - without having to modify the disribution's config files (which
might not be possible if the kernel is on a live CD, etc.).

Also, while at it, clean up the sysrq interfaces.

[bunk@stusta.de: make sysrq_always_enabled_setup() static]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index d8323b8893c3..ef69c75780bf 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -1656,6 +1656,12 @@ and is between 256 and 4096 characters. It is defined in the file
         sym53c416=      [HW,SCSI]
                         See header of drivers/scsi/sym53c416.c.
 
+        sysrq_always_enabled
+                        [KNL]
+                        Ignore sysrq setting - this boot parameter will
+                        neutralize any effect of /proc/sys/kernel/sysrq.
+                        Useful for debugging.
+
         t128=           [HW,SCSI]
                         See header of drivers/scsi/t128.c.