Revert "ipmi: add new IPMI nmi watchdog handling"
This reverts commit f64da958dfc83335de1d2bef9d3868f30feb4e53.
Andi Kleen is unhappy with the changes, and they really do not seem
worth it. IPMI could use DIE_NMI_IPI instead of the new callback, even
though that ends up having its own set of problems too, mainly because
the IPMI code cannot really know the NMI was from IPMI or not.
Manually fix up conflicts in arch/x86_64/kernel/traps.c and
drivers/char/ipmi/ipmi_watchdog.c.
Cc: Andi Kleen <ak@suse.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Corey Minyard <minyard@acm.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/i386/kernel/traps.c b/arch/i386/kernel/traps.c
index c05e7e8..90da057 100644
--- a/arch/i386/kernel/traps.c
+++ b/arch/i386/kernel/traps.c
@@ -733,11 +733,6 @@
*/
if (nmi_watchdog_tick(regs, reason))
return;
-#endif
- if (notify_die(DIE_NMI_POST, "nmi_post", regs, reason, 2, 0)
- == NOTIFY_STOP)
- return;
-#ifdef CONFIG_X86_LOCAL_APIC
if (!do_nmi_callback(regs, smp_processor_id()))
#endif
unknown_nmi_error(reason, regs);
diff --git a/arch/x86_64/kernel/traps.c b/arch/x86_64/kernel/traps.c
index d28f013..cb29fb9 100644
--- a/arch/x86_64/kernel/traps.c
+++ b/arch/x86_64/kernel/traps.c
@@ -776,9 +776,6 @@
*/
if (nmi_watchdog_tick(regs,reason))
return;
- if (notify_die(DIE_NMI_POST, "nmi_post", regs, reason, 2, 0)
- == NOTIFY_STOP)
- return;
if (!do_nmi_callback(regs,cpu))
unknown_nmi_error(reason, regs);
diff --git a/drivers/char/ipmi/ipmi_watchdog.c b/drivers/char/ipmi/ipmi_watchdog.c
index 147c120..41f78e2 100644
--- a/drivers/char/ipmi/ipmi_watchdog.c
+++ b/drivers/char/ipmi/ipmi_watchdog.c
@@ -50,18 +50,10 @@
#include <linux/poll.h>
#include <linux/string.h>
#include <linux/ctype.h>
-#include <linux/delay.h>
#include <asm/atomic.h>
-#ifdef CONFIG_X86
-/* This is ugly, but I've determined that x86 is the only architecture
- that can reasonably support the IPMI NMI watchdog timeout at this
- time. If another architecture adds this capability somehow, it
- will have to be a somewhat different mechanism and I have no idea
- how it will work. So in the unlikely event that another
- architecture supports this, we can figure out a good generic
- mechanism for it at that time. */
-#define HAVE_DIE_NMI_POST
+#ifdef CONFIG_X86_LOCAL_APIC
+#include <asm/apic.h>
#endif
#define PFX "IPMI Watchdog: "
@@ -327,11 +319,6 @@
/* If a pretimeout occurs, this is used to allow only one panic to happen. */
static atomic_t preop_panic_excl = ATOMIC_INIT(-1);
-#ifdef HAVE_DIE_NMI_POST
-static int testing_nmi;
-static int nmi_handler_registered;
-#endif
-
static int ipmi_heartbeat(void);
static void panic_halt_ipmi_heartbeat(void);
@@ -373,10 +360,6 @@
int hbnow = 0;
- /* These can be cleared as we are setting the timeout. */
- ipmi_start_timer_on_heartbeat = 0;
- pretimeout_since_last_heartbeat = 0;
-
data[0] = 0;
WDOG_SET_TIMER_USE(data[0], WDOG_TIMER_USE_SMS_OS);
@@ -451,12 +434,13 @@
wait_for_completion(&set_timeout_wait);
- mutex_unlock(&set_timeout_lock);
-
if ((do_heartbeat == IPMI_SET_TIMEOUT_FORCE_HB)
|| ((send_heartbeat_now)
&& (do_heartbeat == IPMI_SET_TIMEOUT_HB_IF_NECESSARY)))
+ {
rv = ipmi_heartbeat();
+ }
+ mutex_unlock(&set_timeout_lock);
out:
return rv;
@@ -536,10 +520,12 @@
int rv;
struct ipmi_system_interface_addr addr;
- if (ipmi_ignore_heartbeat)
+ if (ipmi_ignore_heartbeat) {
return 0;
+ }
if (ipmi_start_timer_on_heartbeat) {
+ ipmi_start_timer_on_heartbeat = 0;
ipmi_watchdog_state = action_val;
return ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB);
} else if (pretimeout_since_last_heartbeat) {
@@ -547,6 +533,7 @@
We don't want to set the action, though, we want to
leave that alone (thus it can't be combined with the
above operation. */
+ pretimeout_since_last_heartbeat = 0;
return ipmi_set_timeout(IPMI_SET_TIMEOUT_HB_IF_NECESSARY);
}
@@ -934,45 +921,6 @@
printk(KERN_CRIT PFX "Unable to register misc device\n");
}
-#ifdef HAVE_DIE_NMI_POST
- if (nmi_handler_registered) {
- int old_pretimeout = pretimeout;
- int old_timeout = timeout;
- int old_preop_val = preop_val;
-
- /* Set the pretimeout to go off in a second and give
- ourselves plenty of time to stop the timer. */
- ipmi_watchdog_state = WDOG_TIMEOUT_RESET;
- preop_val = WDOG_PREOP_NONE; /* Make sure nothing happens */
- pretimeout = 99;
- timeout = 100;
-
- testing_nmi = 1;
-
- rv = ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB);
- if (rv) {
- printk(KERN_WARNING PFX "Error starting timer to"
- " test NMI: 0x%x. The NMI pretimeout will"
- " likely not work\n", rv);
- rv = 0;
- goto out_restore;
- }
-
- msleep(1500);
-
- if (testing_nmi != 2) {
- printk(KERN_WARNING PFX "IPMI NMI didn't seem to"
- " occur. The NMI pretimeout will"
- " likely not work\n");
- }
- out_restore:
- testing_nmi = 0;
- preop_val = old_preop_val;
- pretimeout = old_pretimeout;
- timeout = old_timeout;
- }
-#endif
-
out:
up_write(®ister_sem);
@@ -982,10 +930,6 @@
ipmi_watchdog_state = action_val;
ipmi_set_timeout(IPMI_SET_TIMEOUT_FORCE_HB);
printk(KERN_INFO PFX "Starting now!\n");
- } else {
- /* Stop the timer now. */
- ipmi_watchdog_state = WDOG_TIMEOUT_NONE;
- ipmi_set_timeout(IPMI_SET_TIMEOUT_NO_HB);
}
}
@@ -1022,28 +966,17 @@
up_write(®ister_sem);
}
-#ifdef HAVE_DIE_NMI_POST
+#ifdef HAVE_NMI_HANDLER
static int
-ipmi_nmi(struct notifier_block *self, unsigned long val, void *data)
+ipmi_nmi(void *dev_id, int cpu, int handled)
{
- if (val != DIE_NMI_POST)
- return NOTIFY_OK;
-
- if (testing_nmi) {
- testing_nmi = 2;
- return NOTIFY_STOP;
- }
-
/* If we are not expecting a timeout, ignore it. */
if (ipmi_watchdog_state == WDOG_TIMEOUT_NONE)
- return NOTIFY_OK;
-
- if (preaction_val != WDOG_PRETIMEOUT_NMI)
- return NOTIFY_OK;
+ return NOTIFY_DONE;
/* If no one else handled the NMI, we assume it was the IPMI
watchdog. */
- if (preop_val == WDOG_PREOP_PANIC) {
+ if ((!handled) && (preop_val == WDOG_PREOP_PANIC)) {
/* On some machines, the heartbeat will give
an error and not work unless we re-enable
the timer. So do so. */
@@ -1052,12 +985,18 @@
panic(PFX "pre-timeout");
}
- return NOTIFY_STOP;
+ return NOTIFY_DONE;
}
-static struct notifier_block ipmi_nmi_handler = {
- .notifier_call = ipmi_nmi
+static struct nmi_handler ipmi_nmi_handler =
+{
+ .link = LIST_HEAD_INIT(ipmi_nmi_handler.link),
+ .dev_name = "ipmi_watchdog",
+ .dev_id = NULL,
+ .handler = ipmi_nmi,
+ .priority = 0, /* Call us last. */
};
+int nmi_handler_registered;
#endif
static int wdog_reboot_handler(struct notifier_block *this,
@@ -1174,7 +1113,7 @@
preaction_val = WDOG_PRETIMEOUT_NONE;
else if (strcmp(inval, "pre_smi") == 0)
preaction_val = WDOG_PRETIMEOUT_SMI;
-#ifdef HAVE_DIE_NMI_POST
+#ifdef HAVE_NMI_HANDLER
else if (strcmp(inval, "pre_nmi") == 0)
preaction_val = WDOG_PRETIMEOUT_NMI;
#endif
@@ -1208,7 +1147,7 @@
static void check_parms(void)
{
-#ifdef HAVE_DIE_NMI_POST
+#ifdef HAVE_NMI_HANDLER
int do_nmi = 0;
int rv;
@@ -1221,9 +1160,20 @@
preop_op("preop_none", NULL);
do_nmi = 0;
}
+#ifdef CONFIG_X86_LOCAL_APIC
+ if (nmi_watchdog == NMI_IO_APIC) {
+ printk(KERN_WARNING PFX "nmi_watchdog is set to IO APIC"
+ " mode (value is %d), that is incompatible"
+ " with using NMI in the IPMI watchdog."
+ " Disabling IPMI nmi pretimeout.\n",
+ nmi_watchdog);
+ preaction_val = WDOG_PRETIMEOUT_NONE;
+ do_nmi = 0;
+ }
+#endif
}
if (do_nmi && !nmi_handler_registered) {
- rv = register_die_notifier(&ipmi_nmi_handler);
+ rv = request_nmi(&ipmi_nmi_handler);
if (rv) {
printk(KERN_WARNING PFX
"Can't register nmi handler\n");
@@ -1231,7 +1181,7 @@
} else
nmi_handler_registered = 1;
} else if (!do_nmi && nmi_handler_registered) {
- unregister_die_notifier(&ipmi_nmi_handler);
+ release_nmi(&ipmi_nmi_handler);
nmi_handler_registered = 0;
}
#endif
@@ -1267,9 +1217,9 @@
rv = ipmi_smi_watcher_register(&smi_watcher);
if (rv) {
-#ifdef HAVE_DIE_NMI_POST
- if (nmi_handler_registered)
- unregister_die_notifier(&ipmi_nmi_handler);
+#ifdef HAVE_NMI_HANDLER
+ if (preaction_val == WDOG_PRETIMEOUT_NMI)
+ release_nmi(&ipmi_nmi_handler);
#endif
atomic_notifier_chain_unregister(&panic_notifier_list,
&wdog_panic_notifier);
@@ -1288,9 +1238,9 @@
ipmi_smi_watcher_unregister(&smi_watcher);
ipmi_unregister_watchdog(watchdog_ifnum);
-#ifdef HAVE_DIE_NMI_POST
+#ifdef HAVE_NMI_HANDLER
if (nmi_handler_registered)
- unregister_die_notifier(&ipmi_nmi_handler);
+ release_nmi(&ipmi_nmi_handler);
#endif
atomic_notifier_chain_unregister(&panic_notifier_list,
diff --git a/include/asm-i386/kdebug.h b/include/asm-i386/kdebug.h
index 05c3117..a185b5f 100644
--- a/include/asm-i386/kdebug.h
+++ b/include/asm-i386/kdebug.h
@@ -27,7 +27,6 @@
DIE_GPF,
DIE_CALL,
DIE_NMI_IPI,
- DIE_NMI_POST,
DIE_PAGE_FAULT,
};
diff --git a/include/asm-x86_64/kdebug.h b/include/asm-x86_64/kdebug.h
index 74feae9..d7e2bcf 100644
--- a/include/asm-x86_64/kdebug.h
+++ b/include/asm-x86_64/kdebug.h
@@ -22,7 +22,6 @@
DIE_GPF,
DIE_CALL,
DIE_NMI_IPI,
- DIE_NMI_POST,
DIE_PAGE_FAULT,
};