lkdtm: add debugfs access and loosen KPROBE ties

Add adds a debugfs interface and additional failure modes to LKDTM to
provide similar functionality to the provoke-crash driver submitted here:

  http://lwn.net/Articles/371208/

Crashes can now be induced either through module parameters (as before)
or through the debugfs interface as in provoke-crash.

The patch also provides a new "direct" interface, where KPROBES are not
used, i.e., the crash is invoked directly upon write to the debugfs
file. When built without KPROBES configured, only this mode is available.

Signed-off-by: Simon Kagstrom <simon.kagstrom@netinsight.net>
Cc: M. Mohan Kumar <mohan@in.ibm.com>
Cc: Americo Wang <xiyou.wangcong@gmail.com>
Cc: David Woodhouse <dwmw2@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>,
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 3 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 5e3407d997b2..b520ec1f33c5 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -864,8 +864,7 @@ config DEBUG_FORCE_WEAK_PER_CPU
 
 config LKDTM
         tristate "Linux Kernel Dump Test Tool Module"
-        depends on DEBUG_KERNEL
-        depends on KPROBES
+        depends on DEBUG_FS
         depends on BLOCK
         default n
         help
@@ -876,7 +875,7 @@ config LKDTM
         called lkdtm.
 
         Documentation on how to use the module can be found in
-        drivers/misc/lkdtm.c
+        Documentation/fault-injection/provoke-crashes.txt
 
 config FAULT_INJECTION
         bool "Fault-injection framework"