5 files changed, 61 insertions, 31 deletions

diff --git a/arch/x86/include/asm/io_apic.h b/arch/x86/include/asm/io_apic.h
index 73d8c5398ea9..d59e17232c4d 100644
--- a/arch/x86/include/asm/io_apic.h
+++ b/arch/x86/include/asm/io_apic.h
@@ -179,6 +179,7 @@ extern void __init native_io_apic_init_mappings(void);
 extern unsigned int native_io_apic_read(unsigned int apic, unsigned int reg);
 extern void native_io_apic_write(unsigned int apic, unsigned int reg, unsigned int val);
 extern void native_io_apic_modify(unsigned int apic, unsigned int reg, unsigned int val);
+extern void native_disable_io_apic(void);
 
 static inline unsigned int io_apic_read(unsigned int apic, unsigned int reg)
 {
@@ -223,6 +224,7 @@ static inline void disable_ioapic_support(void) { }
 #define native_io_apic_read             NULL
 #define native_io_apic_write            NULL
 #define native_io_apic_modify           NULL
+#define native_disable_io_apic          NULL
 #endif
 
 #endif /* _ASM_X86_IO_APIC_H */
diff --git a/arch/x86/include/asm/x86_init.h b/arch/x86/include/asm/x86_init.h
index 57693498519c..b1d2d6aefcc9 100644
--- a/arch/x86/include/asm/x86_init.h
+++ b/arch/x86/include/asm/x86_init.h
@@ -190,10 +190,11 @@ struct x86_msi_ops {
 };
 
 struct x86_io_apic_ops {
-        void            (*init)  (void);
-        unsigned int    (*read)  (unsigned int apic, unsigned int reg);
-        void            (*write) (unsigned int apic, unsigned int reg, unsigned int value);
-        void            (*modify)(unsigned int apic, unsigned int reg, unsigned int value);
+        void            (*init)   (void);
+        unsigned int    (*read)   (unsigned int apic, unsigned int reg);
+        void            (*write)  (unsigned int apic, unsigned int reg, unsigned int value);
+        void            (*modify) (unsigned int apic, unsigned int reg, unsigned int value);
+        void            (*disable)(void);
 };
 
 extern struct x86_init_ops x86_init;
diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 2016f9dabd72..cd5f4d7cc163 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -1921,30 +1921,14 @@ void __init enable_IO_APIC(void)
         clear_IO_APIC();
 }
 
-/*
- * Not an __init, needed by the reboot code
- */
-void disable_IO_APIC(void)
+void native_disable_io_apic(void)
 {
         /*
-         * Clear the IO-APIC before rebooting:
-         */
-        clear_IO_APIC();
-
-        if (!legacy_pic->nr_legacy_irqs)
-                return;
-
-        /*
          * If the i8259 is routed through an IOAPIC
          * Put that IOAPIC in virtual wire mode
          * so legacy interrupts can be delivered.
-         *
-         * With interrupt-remapping, for now we will use virtual wire A mode,
-         * as virtual wire B is little complex (need to configure both
-         * IOAPIC RTE as well as interrupt-remapping table entry).
-         * As this gets called during crash dump, keep this simple for now.
          */
-        if (ioapic_i8259.pin != -1 && !irq_remapping_enabled) {
+        if (ioapic_i8259.pin != -1) {
                 struct IO_APIC_route_entry entry;
 
                 memset(&entry, 0, sizeof(entry));
@@ -1964,12 +1948,25 @@ void disable_IO_APIC(void)
                 ioapic_write_entry(ioapic_i8259.apic, ioapic_i8259.pin, entry);
         }
 
+        if (cpu_has_apic || apic_from_smp_config())
+                disconnect_bsp_APIC(ioapic_i8259.pin != -1);
+
+}
+
+/*
+ * Not an __init, needed by the reboot code
+ */
+void disable_IO_APIC(void)
+{
         /*
-         * Use virtual wire A mode when interrupt remapping is enabled.
+         * Clear the IO-APIC before rebooting:
          */
-        if (cpu_has_apic || apic_from_smp_config())
-                disconnect_bsp_APIC(!irq_remapping_enabled &&
-                                ioapic_i8259.pin != -1);
+        clear_IO_APIC();
+
+        if (!legacy_pic->nr_legacy_irqs)
+                return;
+
+        x86_io_apic_ops.disable();
 }
 
 #ifdef CONFIG_X86_32
diff --git a/arch/x86/kernel/x86_init.c b/arch/x86/kernel/x86_init.c
index 7a3d075a814a..754524acc845 100644
--- a/arch/x86/kernel/x86_init.c
+++ b/arch/x86/kernel/x86_init.c
@@ -118,8 +118,9 @@ struct x86_msi_ops x86_msi = {
 };
 
 struct x86_io_apic_ops x86_io_apic_ops = {
-        .init   = native_io_apic_init_mappings,
-        .read   = native_io_apic_read,
-        .write  = native_io_apic_write,
-        .modify = native_io_apic_modify,
+        .init                   = native_io_apic_init_mappings,
+        .read                   = native_io_apic_read,
+        .write                  = native_io_apic_write,
+        .modify                 = native_io_apic_modify,
+        .disable                = native_disable_io_apic,
 };
diff --git a/drivers/iommu/irq_remapping.c b/drivers/iommu/irq_remapping.c
index 19381b90e619..db3dcaf4ddf0 100644
--- a/drivers/iommu/irq_remapping.c
+++ b/drivers/iommu/irq_remapping.c
@@ -1,3 +1,4 @@
+#include <linux/cpumask.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
 #include <linux/cpumask.h>
@@ -6,6 +7,9 @@
 
 #include <asm/hw_irq.h>
 #include <asm/irq_remapping.h>
+#include <asm/processor.h>
+#include <asm/x86_init.h>
+#include <asm/apic.h>
 
 #include "irq_remapping.h"
 
@@ -17,6 +21,24 @@ int no_x2apic_optout;
 
 static struct irq_remap_ops *remap_ops;
 
+static void irq_remapping_disable_io_apic(void)
+{
+        /*
+         * With interrupt-remapping, for now we will use virtual wire A
+         * mode, as virtual wire B is little complex (need to configure
+         * both IOAPIC RTE as well as interrupt-remapping table entry).
+         * As this gets called during crash dump, keep this simple for
+         * now.
+         */
+        if (cpu_has_apic || apic_from_smp_config())
+                disconnect_bsp_APIC(0);
+}
+
+static void __init irq_remapping_modify_x86_ops(void)
+{
+        x86_io_apic_ops.disable =       irq_remapping_disable_io_apic;
+}
+
 static __init int setup_nointremap(char *str)
 {
         disable_irq_remap = 1;
@@ -79,10 +101,17 @@ int __init irq_remapping_prepare(void)
 
 int __init irq_remapping_enable(void)
 {
+        int ret;
+
         if (!remap_ops || !remap_ops->enable)
                 return -ENODEV;
 
-        return remap_ops->enable();
+        ret = remap_ops->enable();
+
+        if (irq_remapping_enabled)
+                irq_remapping_modify_x86_ops();
+
+        return ret;
 }
 
 void irq_remapping_disable(void)