[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>
diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index b905d7b..cf45bed 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -41,6 +41,11 @@
#include "io_ports.h"
/*
+ * Knob to control our willingness to enable the local APIC.
+ */
+int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
+
+/*
* Debug level
*/
int apic_verbosity;
@@ -666,26 +671,6 @@
* Original code written by Keir Fraser.
*/
-/*
- * Knob to control our willingness to enable the local APIC.
- */
-int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
-
-static int __init lapic_disable(char *str)
-{
- enable_local_apic = -1;
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
- return 0;
-}
-__setup("nolapic", lapic_disable);
-
-static int __init lapic_enable(char *str)
-{
- enable_local_apic = 1;
- return 0;
-}
-__setup("lapic", lapic_enable);
-
static int __init apic_set_verbosity(char *str)
{
if (strcmp("debug", str) == 0)
diff --git a/arch/i386/kernel/setup.c b/arch/i386/kernel/setup.c
index cba67e4..f1ad9fd 100644
--- a/arch/i386/kernel/setup.c
+++ b/arch/i386/kernel/setup.c
@@ -44,6 +44,7 @@
#include <linux/edd.h>
#include <linux/nodemask.h>
#include <video/edid.h>
+#include <asm/apic.h>
#include <asm/e820.h>
#include <asm/mpspec.h>
#include <asm/setup.h>
@@ -835,6 +836,16 @@
#endif /* CONFIG_X86_LOCAL_APIC */
#endif /* CONFIG_ACPI_BOOT */
+#ifdef CONFIG_X86_LOCAL_APIC
+ /* enable local APIC */
+ else if (!memcmp(from, "lapic", 5))
+ lapic_enable();
+
+ /* disable local APIC */
+ else if (!memcmp(from, "nolapic", 6))
+ lapic_disable();
+#endif /* CONFIG_X86_LOCAL_APIC */
+
/*
* highmem=size forces highmem to be exactly 'size' bytes.
* This works even on boxes that have no highmem otherwise.
diff --git a/include/asm-i386/apic.h b/include/asm-i386/apic.h
index a5810cf..53268cd 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