[PATCH] kexec: x86: resture apic virtual wire mode on shutdown

When coming out of apic mode attempt to set the appropriate
apic back into virtual wire mode.  This improves on previous versions
of this patch by by never setting bot the local apic and the ioapic
into veritual wire mode.

This code looks at data from the mptable to see if an ioapic has
an ExtInt input to make this decision.  A future improvement
is to figure out which apic or ioapic was in virtual wire mode
at boot time and to remember it.  That is potentially a more accurate
method, of selecting which apic to place in virutal wire mode.

Signed-off-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

2 files changed, 2 insertions, 1 deletions

diff --git a/include/asm-i386/apic.h b/include/asm-i386/apic.h
index 53268cd9306e..6a1b1882285c 100644
--- a/include/asm-i386/apic.h
+++ b/include/asm-i386/apic.h
@@ -100,7 +100,7 @@ extern void (*wait_timer_tick)(void);
 extern int get_maxlvt(void);
 extern void clear_local_APIC(void);
 extern void connect_bsp_APIC (void);
-extern void disconnect_bsp_APIC (void);
+extern void disconnect_bsp_APIC (int virt_wire_setup);
 extern void disable_local_APIC (void);
 extern void lapic_shutdown (void);
 extern int verify_local_APIC (void);
diff --git a/include/asm-i386/apicdef.h b/include/asm-i386/apicdef.h
index 41e8d2d918e0..0fed5e3c699c 100644
--- a/include/asm-i386/apicdef.h
+++ b/include/asm-i386/apicdef.h
@@ -86,6 +86,7 @@
 #define                 APIC_LVT_REMOTE_IRR             (1<<14)
 #define                 APIC_INPUT_POLARITY             (1<<13)
 #define                 APIC_SEND_PENDING               (1<<12)
+#define                 APIC_MODE_MASK                  0x700
 #define                 GET_APIC_DELIVERY_MODE(x)       (((x)>>8)&0x7)
 #define                 SET_APIC_DELIVERY_MODE(x,y)     (((x)&~0x700)|((y)<<8))
 #define                         APIC_MODE_FIXED         0x0