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authorDon Zickus <dzickus@redhat.com>2006-09-26 10:52:27 +0200
committerAndi Kleen <andi@basil.nowhere.org>2006-09-26 10:52:27 +0200
commit407984f1af259b31957c7c05075a454a751bb801 (patch)
tree1e9318b4255957c27a4dbacd84711604bf789393 /arch
parent2fbe7b25c8edaf2d10e6c1a4cc9f8afe714c4764 (diff)
[PATCH] x86: Add abilty to enable/disable nmi watchdog with sysctl
Adds a new /proc/sys/kernel/nmi call that will enable/disable the nmi watchdog. Signed-off-by: Don Zickus <dzickus@redhat.com> Signed-off-by: Andi Kleen <ak@suse.de>
Diffstat (limited to 'arch')
-rw-r--r--arch/i386/kernel/nmi.c52
-rw-r--r--arch/x86_64/kernel/nmi.c48
2 files changed, 100 insertions, 0 deletions
diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index acd3fdea2a2..28065d0b71a 100644
--- a/arch/i386/kernel/nmi.c
+++ b/arch/i386/kernel/nmi.c
@@ -846,6 +846,58 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu)
return 0;
}
+/*
+ * proc handler for /proc/sys/kernel/nmi_watchdog
+ */
+int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
+ void __user *buffer, size_t *length, loff_t *ppos)
+{
+ int old_state;
+
+ nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0;
+ old_state = nmi_watchdog_enabled;
+ proc_dointvec(table, write, file, buffer, length, ppos);
+ if (!!old_state == !!nmi_watchdog_enabled)
+ return 0;
+
+ if (atomic_read(&nmi_active) < 0) {
+ printk(KERN_WARNING "NMI watchdog is permanently disabled\n");
+ return -EINVAL;
+ }
+
+ if (nmi_watchdog == NMI_DEFAULT) {
+ if (nmi_known_cpu() > 0)
+ nmi_watchdog = NMI_LOCAL_APIC;
+ else
+ nmi_watchdog = NMI_IO_APIC;
+ }
+
+ if (nmi_watchdog == NMI_LOCAL_APIC)
+ {
+ if (nmi_watchdog_enabled)
+ enable_lapic_nmi_watchdog();
+ else
+ disable_lapic_nmi_watchdog();
+ } else if (nmi_watchdog == NMI_IO_APIC) {
+ /* FIXME
+ * for some reason these functions don't work
+ */
+ printk("Can not enable/disable NMI on IO APIC\n");
+ return -EINVAL;
+#if 0
+ if (nmi_watchdog_enabled)
+ enable_timer_nmi_watchdog();
+ else
+ disable_timer_nmi_watchdog();
+#endif
+ } else {
+ printk( KERN_WARNING
+ "NMI watchdog doesn't know what hardware to touch\n");
+ return -EIO;
+ }
+ return 0;
+}
+
#endif
EXPORT_SYMBOL(nmi_active);
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index 9d175dcf3a2..3a17411a9a1 100644
--- a/arch/x86_64/kernel/nmi.c
+++ b/arch/x86_64/kernel/nmi.c
@@ -750,6 +750,54 @@ static int unknown_nmi_panic_callback(struct pt_regs *regs, int cpu)
return 0;
}
+/*
+ * proc handler for /proc/sys/kernel/nmi
+ */
+int proc_nmi_enabled(struct ctl_table *table, int write, struct file *file,
+ void __user *buffer, size_t *length, loff_t *ppos)
+{
+ int old_state;
+
+ nmi_watchdog_enabled = (atomic_read(&nmi_active) > 0) ? 1 : 0;
+ old_state = nmi_watchdog_enabled;
+ proc_dointvec(table, write, file, buffer, length, ppos);
+ if (!!old_state == !!nmi_watchdog_enabled)
+ return 0;
+
+ if (atomic_read(&nmi_active) < 0) {
+ printk( KERN_WARNING "NMI watchdog is permanently disabled\n");
+ return -EINVAL;
+ }
+
+ /* if nmi_watchdog is not set yet, then set it */
+ nmi_watchdog_default();
+
+ if (nmi_watchdog == NMI_LOCAL_APIC)
+ {
+ if (nmi_watchdog_enabled)
+ enable_lapic_nmi_watchdog();
+ else
+ disable_lapic_nmi_watchdog();
+ } else if (nmi_watchdog == NMI_IO_APIC) {
+ /* FIXME
+ * for some reason these functions don't work
+ */
+ printk("Can not enable/disable NMI on IO APIC\n");
+ return -EIO;
+#if 0
+ if (nmi_watchdog_enabled)
+ enable_timer_nmi_watchdog();
+ else
+ disable_timer_nmi_watchdog();
+#endif
+ } else {
+ printk(KERN_WARNING
+ "NMI watchdog doesn't know what hardware to touch\n");
+ return -EIO;
+ }
+ return 0;
+}
+
#endif
EXPORT_SYMBOL(nmi_active);