[PATCH] x86-64: Use largest APIC number, not number of CPUs to decide on physflat mode
Handles case where BIOS gives CPUs very large APIC numbers correctly.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/genapic.c b/arch/x86_64/kernel/genapic.c
index b1c144f..f3159a4 100644
--- a/arch/x86_64/kernel/genapic.c
+++ b/arch/x86_64/kernel/genapic.c
@@ -45,7 +45,7 @@
u8 clusters, max_cluster;
u8 id;
u8 cluster_cnt[NUM_APIC_CLUSTERS];
- int num_cpus = 0;
+ int max_apic = 0;
#if defined(CONFIG_ACPI)
/*
@@ -64,7 +64,8 @@
id = bios_cpu_apicid[i];
if (id == BAD_APICID)
continue;
- num_cpus++;
+ if (id > max_apic)
+ max_apic = id;
cluster_cnt[APIC_CLUSTERID(id)]++;
}
@@ -79,7 +80,7 @@
we have ACPI platform support for CPU hotplug
we should detect hotplug capablity from ACPI tables and
only do this when really needed. -AK */
- if (num_cpus <= 8)
+ if (max_apic <= 8)
genapic = &apic_flat;
#endif
goto print;