i386: fix NMI watchdog not reserving its MSRs

At system boot time, the NMI watchdog no longer reserved its MSRs, allowing
other subsystems to mess with them.  Fix that.

Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/i386/kernel/cpu/perfctr-watchdog.c b/arch/i386/kernel/cpu/perfctr-watchdog.c
index 2b04c8f1db62..8343244b72c4 100644
--- a/arch/i386/kernel/cpu/perfctr-watchdog.c
+++ b/arch/i386/kernel/cpu/perfctr-watchdog.c
@@ -614,6 +614,12 @@ int lapic_watchdog_init(unsigned nmi_hz)
                 probe_nmi_watchdog();
                 if (!wd_ops)
                         return -1;
+
+                if (!wd_ops->reserve()) {
+                        printk(KERN_ERR
+                                "NMI watchdog: cannot reserve perfctrs\n");
+                        return -1;
+                }
         }
 
         if (!(wd_ops->setup(nmi_hz))) {