Re: 2.4.19-rc3-ac2 SMP

[James Cleverdon <jamesclv@us.ibm.com>]

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On Wednesday 24 July 2002 08:26 am, Zwane Mwaikambo wrote:
[ Snip! ]
>raw_phys_apicid[]=       00 01 02 03 00 00 00 00 00 00 00 00 00 00 00 00 00
>00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
> cpu_2_logical_apicid[]=  01 01 02 08 FF FF FF FF FF FF FF FF FF FF FF FF FF
> FF FF FF FF FF FF FF FF FF FF FF FF FF FF FF
> cpu_2_physical_apicid[]= 02 00 01 03 FF FF FF FF FF FF FF FF FF FF FF FF FF
> FF F F FF FF FF FF FF FF FF FF FF FF FF FF FF

Ah ha!  Note that while the CPU records in the {MPS,ACPI/MADT} table are in 
numerical order (as preserved in raw_phys_apicid), the boot CPU is # 02.  The 
flat code in smp_boot_cpus assumes that the boot CPU will be the first record 
in the list.  Oops.

Try the attached patch and see if it helps.

[ Snip! ]

>
> Regards,
> 	Zwane

-- 
James Cleverdon
IBM xSeries Linux Solutions
{jamesclv(Unix, preferred), cleverdj(Notes)} at us dot ibm dot com

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--- ac3/arch/i386/kernel/smpboot.c.df	Tue Jul 23 15:02:49 2002
+++ ac3/arch/i386/kernel/smpboot.c	Wed Jul 24 18:02:24 2002
@@ -1077,6 +1077,7 @@
 	 */
 	Dprintk("CPU present map: %lx\n", phys_cpu_present_map);
 
+	cpu = 1;
 	for (bit = 0; bit < NR_CPUS; bit++) {
 		if (!(phys_cpu_present_map & (1UL << bit)))
 			continue;
@@ -1093,7 +1094,7 @@
 		else if (clustered_apic_logical)
 			log_apicid = ((bit >> 2) << 4) | (1 << (bit & 0x3));
 		else
-			log_apicid = 1u << bit;
+			log_apicid = 1u << cpu;
 
 		do_boot_cpu(phys_apicid, log_apicid);
 
@@ -1104,6 +1105,8 @@
 				(phys_cpu_present_map & (1ul << bit)))
 			printk("CPU #%d not responding - cannot use it.\n",
 								bit);
+		else
+			++cpu;
 	}
 
 	/*