hard_smp_processor_id used to be just a macro that hard-coded
hard_smp_processor_id to 0 in the non SMP case. When booting non SMP
kernels on hardware where the boot ioapic id is not 0 this turns out to
be a problem. This is happens frequently in the case of kdump and once
in a great while in the case of real hardware.
Use the APIC to determine the hardware processor id in both UP and SMP
kernels to fix this issue.
Notice that hard_smp_processor_id is only used by SMP code or by code
that works with apics so we do not need to handle the case when apics
are not present and hard_smp_processor_id should never be called there.
Signed-off-by: Fernando Luis Vazquez Cao <[EMAIL PROTECTED]>
---
diff -urNp linux-2.6.21-rc5-orig/arch/i386/mach-generic/probe.c
linux-2.6.21-rc5/arch/i386/mach-generic/probe.c
--- linux-2.6.21-rc5-orig/arch/i386/mach-generic/probe.c 2007-02-05
03:44:54.000000000 +0900
+++ linux-2.6.21-rc5/arch/i386/mach-generic/probe.c 2007-04-04
16:19:53.000000000 +0900
@@ -119,9 +119,7 @@ int __init acpi_madt_oem_check(char *oem
return 0;
}
-#ifdef CONFIG_SMP
int hard_smp_processor_id(void)
{
return genapic->get_apic_id(*(unsigned long *)(APIC_BASE+APIC_ID));
}
-#endif
diff -urNp linux-2.6.21-rc5-orig/include/asm-i386/smp.h
linux-2.6.21-rc5/include/asm-i386/smp.h
--- linux-2.6.21-rc5-orig/include/asm-i386/smp.h 2007-04-04
15:57:31.000000000 +0900
+++ linux-2.6.21-rc5/include/asm-i386/smp.h 2007-04-04 16:14:54.000000000
+0900
@@ -74,20 +74,6 @@ static inline int num_booting_cpus(void)
return cpus_weight(cpu_callout_map);
}
-#ifdef CONFIG_X86_LOCAL_APIC
-
-#ifdef APIC_DEFINITION
-extern int hard_smp_processor_id(void);
-#else
-#include <mach_apicdef.h>
-static inline int hard_smp_processor_id(void)
-{
- /* we don't want to mark this access volatile - bad code generation */
- return GET_APIC_ID(*(unsigned long *)(APIC_BASE+APIC_ID));
-}
-#endif
-#endif
-
extern int safe_smp_processor_id(void);
extern int __cpu_disable(void);
extern void __cpu_die(unsigned int cpu);
@@ -97,7 +83,6 @@ extern unsigned int num_processors;
#else /* CONFIG_SMP */
-#define hard_smp_processor_id() 0
#define safe_smp_processor_id() 0
#define cpu_physical_id(cpu) boot_cpu_physical_apicid
@@ -107,6 +92,27 @@ extern unsigned int num_processors;
#ifndef __ASSEMBLY__
+#ifdef CONFIG_X86_LOCAL_APIC
+
+#ifdef APIC_DEFINITION
+extern int hard_smp_processor_id(void);
+#else
+#include <mach_apicdef.h>
+static inline int hard_smp_processor_id(void)
+{
+ /* we don't want to mark this access volatile - bad code generation */
+ return GET_APIC_ID(*(unsigned long *)(APIC_BASE+APIC_ID));
+}
+#endif /* APIC_DEFINITION */
+
+#else /* CONFIG_X86_LOCAL_APIC */
+
+#ifndef CONFIG_SMP
+#define hard_smp_processor_id() 0
+#endif
+
+#endif /* CONFIG_X86_LOCAL_APIC */
+
extern u8 apicid_2_node[];
#ifdef CONFIG_X86_LOCAL_APIC
-
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