[PATCH] x86_64: make amd quad core 8 socket system not be clustered_box

[Yinghai Lu]

quad core 8 socket system will have apic id lifting.the apic id range could
be [4, 0x23]. or [8, 0x27]. apic_is_clustered_box will think that need to three 
clusters
and that is large than 2. So it is treated as clustered_box.

and will get

Marking TSC unstable due to TSCs unsynchronized

even the CPUs have X86_FEATURE_CONSTANT_TSC set.

this patch offset back the apic before get apic clusterid.

or use dmi to get apic_is_clustered?

Signed-off-by: Yinghai Lu <[EMAIL PROTECTED]>

diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index 9b2be3d..5bdf1bc 100644
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -1223,8 +1223,11 @@ __cpuinit int apic_is_clustered_box(void)
                else
                        break;
 
-               if (id != BAD_APICID)
+               if (id != BAD_APICID) {
+                       if (id >= boot_cpu_id)
+                               id -= boot_cpu_id;
                        __set_bit(APIC_CLUSTERID(id), clustermap);
+               }
        }
 
        /* Problem:  Partially populated chassis may not have CPUs in some of
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/