4 files changed, 72 insertions, 1 deletions

diff --git a/arch/i386/kernel/nmi.c b/arch/i386/kernel/nmi.c
index 7d3f4e22d6fb..b11abacc5cfd 100644
--- a/arch/i386/kernel/nmi.c
+++ b/arch/i386/kernel/nmi.c
@@ -383,6 +383,34 @@ void enable_timer_nmi_watchdog(void)
         }
 }
 
+static void __acpi_nmi_disable(void *__unused)
+{
+        apic_write_around(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED);
+}
+
+/*
+ * Disable timer based NMIs on all CPUs:
+ */
+void acpi_nmi_disable(void)
+{
+        if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
+                on_each_cpu(__acpi_nmi_disable, NULL, 0, 1);
+}
+
+static void __acpi_nmi_enable(void *__unused)
+{
+        apic_write_around(APIC_LVT0, APIC_DM_NMI);
+}
+
+/*
+ * Enable timer based NMIs on all CPUs:
+ */
+void acpi_nmi_enable(void)
+{
+        if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
+                on_each_cpu(__acpi_nmi_enable, NULL, 0, 1);
+}
+
 #ifdef CONFIG_PM
 
 static int nmi_pm_active; /* nmi_active before suspend */
diff --git a/arch/x86_64/kernel/nmi.c b/arch/x86_64/kernel/nmi.c
index e59cda134166..269fe585e71e 100644
--- a/arch/x86_64/kernel/nmi.c
+++ b/arch/x86_64/kernel/nmi.c
@@ -368,6 +368,33 @@ void enable_timer_nmi_watchdog(void)
         }
 }
 
+static void __acpi_nmi_disable(void *__unused)
+{
+        apic_write(APIC_LVT0, APIC_DM_NMI | APIC_LVT_MASKED);
+}
+
+/*
+ * Disable timer based NMIs on all CPUs:
+ */
+void acpi_nmi_disable(void)
+{
+        if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
+                on_each_cpu(__acpi_nmi_disable, NULL, 0, 1);
+}
+
+static void __acpi_nmi_enable(void *__unused)
+{
+        apic_write(APIC_LVT0, APIC_DM_NMI);
+}
+
+/*
+ * Enable timer based NMIs on all CPUs:
+ */
+void acpi_nmi_enable(void)
+{
+        if (atomic_read(&nmi_active) && nmi_watchdog == NMI_IO_APIC)
+                on_each_cpu(__acpi_nmi_enable, NULL, 0, 1);
+}
 #ifdef CONFIG_PM
 
 static int nmi_pm_active; /* nmi_active before suspend */
diff --git a/drivers/acpi/namespace/nsinit.c b/drivers/acpi/namespace/nsinit.c
index 326af8fc0ce7..33db2241044e 100644
--- a/drivers/acpi/namespace/nsinit.c
+++ b/drivers/acpi/namespace/nsinit.c
@@ -45,6 +45,7 @@
 #include <acpi/acnamesp.h>
 #include <acpi/acdispat.h>
 #include <acpi/acinterp.h>
+#include <linux/nmi.h>
 
 #define _COMPONENT          ACPI_NAMESPACE
 ACPI_MODULE_NAME("nsinit")
@@ -534,7 +535,15 @@ acpi_ns_init_one_device(acpi_handle obj_handle,
         info->parameter_type = ACPI_PARAM_ARGS;
         info->flags = ACPI_IGNORE_RETURN_VALUE;
 
+        /*
+         * Some hardware relies on this being executed as atomically
+         * as possible (without an NMI being received in the middle of
+         * this) - so disable NMIs and initialize the device:
+         */
+        acpi_nmi_disable();
         status = acpi_ns_evaluate(info);
+        acpi_nmi_enable();
+
         if (ACPI_SUCCESS(status)) {
                 walk_info->num_INI++;
 
diff --git a/include/linux/nmi.h b/include/linux/nmi.h
index acb4ed130247..29af2d5df097 100644
--- a/include/linux/nmi.h
+++ b/include/linux/nmi.h
@@ -17,8 +17,15 @@
 #ifdef ARCH_HAS_NMI_WATCHDOG
 #include <asm/nmi.h>
 extern void touch_nmi_watchdog(void);
+extern void acpi_nmi_disable(void);
+extern void acpi_nmi_enable(void);
 #else
-# define touch_nmi_watchdog() touch_softlockup_watchdog()
+static inline void touch_nmi_watchdog(void)
+{
+        touch_softlockup_watchdog();
+}
+static inline void acpi_nmi_disable(void) { }
+static inline void acpi_nmi_enable(void) { }
 #endif
 
 #ifndef trigger_all_cpu_backtrace