[PATCH] x86: Allow users to force a panic on NMI

To quote Alan Cox:

The default Linux behaviour on an NMI of either memory or unknown is to
continue operation. For many environments such as scientific computing
it is preferable that the box is taken out and the error dealt with than
an uncorrected parity/ECC error get propogated.

A small number of systems do generate NMI's for bizarre random reasons
such as power management so the default is unchanged. In other respects
the new proc/sys entry works like the existing panic controls already in
that directory.

This is separate to the edac support - EDAC allows supported chipsets to
handle ECC errors well, this change allows unsupported cases to at least
panic rather than cause problems further down the line.

Signed-off-by: Don Zickus <dzickus@redhat.com>
Signed-off-by: Andi Kleen <ak@suse.de>

2 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 2b2ae4fdce8b..1ff9609300b4 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -186,6 +186,7 @@ extern void bust_spinlocks(int yes);
 extern int oops_in_progress;            /* If set, an oops, panic(), BUG() or die() is in progress */
 extern int panic_timeout;
 extern int panic_on_oops;
+extern int panic_on_unrecovered_nmi;
 extern int tainted;
 extern const char *print_tainted(void);
 extern void add_taint(unsigned);
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index ecb79ba52ae1..432778446ad2 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -151,6 +151,7 @@ enum
         KERN_COMPAT_LOG=73,     /* int: print compat layer  messages */
         KERN_MAX_LOCK_DEPTH=74,
         KERN_NMI_WATCHDOG=75, /* int: enable/disable nmi watchdog */
+        KERN_PANIC_ON_NMI=76, /* int: whether we will panic on an unrecovered */
 };