Re: 2.6.16rc5 'found' an extra CPU.

[Ashok Raj]

On Thu, Mar 02, 2006 at 01:44:28PM -0500, Dave Jones wrote:
> I thought I already posted that..
> 

Sorry.. i noticed it later...

I think the problem is the return type u8, and -1 being treated as error
return.

You probably missed the warning that flew by...

could you check if the attached patch works for you?

-- 
Cheers,
Ashok Raj
- Open Source Technology Center


Local apic entries are only 8 bits, but it seemed to not be caught with 
u8 return value result in the check

cpu_index >= NR_CPUS becomming always false.

drivers/acpi/processor_core.c: In function `acpi_processor_get_info':
drivers/acpi/processor_core.c:483: warning: comparison is always false due to limited range of data type


Signed-off-by: Ashok Raj <ashok.raj@xxxxxxxxx>
-----------------------------------------------------
 drivers/acpi/processor_core.c |    8 ++++----
 1 files changed, 4 insertions(+), 4 deletions(-)

Index: linux-2.6.16-rc5-mm1/drivers/acpi/processor_core.c
===================================================================
--- linux-2.6.16-rc5-mm1.orig/drivers/acpi/processor_core.c
+++ linux-2.6.16-rc5-mm1/drivers/acpi/processor_core.c
@@ -395,7 +395,7 @@ static int acpi_processor_remove_fs(stru
 #define ARCH_BAD_APICID		(0xff)
 #endif
 
-static u8 convert_acpiid_to_cpu(u8 acpi_id)
+static int convert_acpiid_to_cpu(u8 acpi_id)
 {
 	u16 apic_id;
 	int i;
@@ -421,7 +421,7 @@ static int acpi_processor_get_info(struc
 	acpi_status status = 0;
 	union acpi_object object = { 0 };
 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
-	u8 cpu_index;
+	int cpu_index;
 	static int cpu0_initialized;
 
 	ACPI_FUNCTION_TRACE("acpi_processor_get_info");
@@ -466,7 +466,7 @@ static int acpi_processor_get_info(struc
 	cpu_index = convert_acpiid_to_cpu(pr->acpi_id);
 
 	/* Handle UP system running SMP kernel, with no LAPIC in MADT */
-	if (!cpu0_initialized && (cpu_index == 0xff) &&
+	if (!cpu0_initialized && (cpu_index == -1) &&
 	    (num_online_cpus() == 1)) {
 		cpu_index = 0;
 	}
@@ -480,7 +480,7 @@ static int acpi_processor_get_info(struc
 	 *  less than the max # of CPUs. They should be ignored _iff
 	 *  they are physically not present.
 	 */
-	if (cpu_index >= NR_CPUS) {
+	if (cpu_index == -1) {
 		if (ACPI_FAILURE
 		    (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
 			ACPI_ERROR((AE_INFO,
-
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