[PATCH] kexec: x86: local apic fix

From: "Maciej W. Rozycki" <macro@linux-mips.org>

Fix a kexec problem whcih causes local APIC detection failure.

The problem is detect_init_APIC() is called early, before the command line
have been processed.  Therefore "lapic" (and "nolapic") have not been seen,
yet.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Signed-off-by: Eric Biederman <ebiederm@xmission.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 13 insertions, 0 deletions

diff --git a/include/asm-i386/apic.h b/include/asm-i386/apic.h
index a5810cf7b578..53268cd9306e 100644
--- a/include/asm-i386/apic.h
+++ b/include/asm-i386/apic.h
@@ -5,6 +5,7 @@
 #include <linux/pm.h>
 #include <asm/fixmap.h>
 #include <asm/apicdef.h>
+#include <asm/processor.h>
 #include <asm/system.h>
 
 #define Dprintk(x...)
@@ -16,8 +17,20 @@
 #define APIC_VERBOSE 1
 #define APIC_DEBUG   2
 
+extern int enable_local_apic;
 extern int apic_verbosity;
 
+static inline void lapic_disable(void)
+{
+        enable_local_apic = -1;
+        clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+}
+
+static inline void lapic_enable(void)
+{
+        enable_local_apic = 1;
+}
+
 /*
  * Define the default level of output to be very little
  * This can be turned up by using apic=verbose for more