[PATCH 2/6] x86: Convert some devices to use DIE_NMIUNKNOWN

From: Don Zickus
Date: Thu Jan 06 2011 - 16:20:38 EST

They are a handful of places in the code that register a die_notifier
as a catch all in case no claims the NMI. Unfortunately, they trigger
on events like DIE_NMI and DIE_NMI_IPI, which depending on when they
registered may collide with other handlers that have the ability to
determine if the NMI is theirs or not.

The function unknown_nmi_error() makes one last effort to walk the
die_chain when no one else has claimed the NMI before spitting out
messages that the NMI is unknown.

This is a better spot for these devices to execute any code without
colliding with the other handlers.

The two drivers modified are only compiled on x86 arches I believe, so
they shouldn't be affected by other arches that may not have

CC: Russ Anderson <rja@xxxxxxx>
CC: Corey Minyard <minyard@xxxxxxx>
CC: openipmi-developer@xxxxxxxxxxxxxxxxxxxxx
CC: dann frazier <dannf@xxxxxx>
Signed-off-by: Don Zickus <dzickus@xxxxxxxxxx>
arch/x86/kernel/apic/x2apic_uv_x.c | 2 +-
drivers/char/ipmi/ipmi_watchdog.c | 2 +-
drivers/watchdog/hpwdt.c | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index e6cde91..7b0d2f6 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -642,7 +642,7 @@ void __cpuinit uv_cpu_init(void)
int uv_handle_nmi(struct notifier_block *self, unsigned long reason, void *data)
- if (reason != DIE_NMI_IPI)
+ if (reason != DIE_NMIUNKNOWN)
return NOTIFY_OK;

if (in_crash_kexec)
diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
index f4d334f..320668f 100644
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -1081,7 +1081,7 @@ ipmi_nmi(struct notifier_block *self, unsigned long val, void *data)
struct die_args *args = data;

- if (val != DIE_NMI)
+ if (val != DIE_NMIUNKNOWN)
return NOTIFY_OK;

/* Hack, if it's a memory or I/O error, ignore it. */
diff --git a/drivers/watchdog/hpwdt.c b/drivers/watchdog/hpwdt.c
index dea7b5b..24b966d 100644
--- a/drivers/watchdog/hpwdt.c
+++ b/drivers/watchdog/hpwdt.c
@@ -469,7 +469,7 @@ static int hpwdt_pretimeout(struct notifier_block *nb, unsigned long ulReason,
unsigned long rom_pl;
static int die_nmi_called;

- if (ulReason != DIE_NMI && ulReason != DIE_NMI_IPI)
+ if (ulReason != DIE_NMIUNKNOWN)
goto out;

if (!hpwdt_nmi_decoding)

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