From: Ravikiran G Thirumalai <kiran@xxxxxxxxxxx> phys_proc_id[] on AMD boxes is right now populated with the initial apic id, obtained by the cpuid instruction. But, the initial apic id need not be the local apic id on clustered APIC systems (see comment at x86_64/kernel/genapic_cluster.c, line 110). On vSMPowered with AMD CPUs the cpu_to_node will turn out to be incorrect (as apicid_to_node[] is indexed by the initial apic id rather than the local apic id). On vSMPowered boxes with Intel CPUs this is working correctly as phys_proc_id[] is initialized correctly in detect_ht(). Following patch fixes AMD boot path according to specification, to use the correct routines for local apic id and socket ids. We use hard_smp_processor_id() to read the local apic id, and phys_pkg_id() to determine socket id for phys_proc_id[] Patch tested on Tyan multicore boxes as well as vSMPowered boxes. Signed-off-by: Ravikiran Thirumalai <kiran@xxxxxxxxxxxx> Signed-off-by: Shai Fultheim <shai@xxxxxxxxxxxx> Signed-off-by: Andi Kleen <ak@xxxxxxx> --- arch/x86_64/kernel/setup.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) Index: linux/arch/x86_64/kernel/setup.c =================================================================== --- linux.orig/arch/x86_64/kernel/setup.c +++ linux/arch/x86_64/kernel/setup.c @@ -846,7 +846,7 @@ static void __init amd_detect_cmp(struct unsigned bits; #ifdef CONFIG_NUMA int node = 0; - unsigned apicid = phys_proc_id[cpu]; + unsigned apicid = hard_smp_processor_id(); #endif bits = 0; @@ -856,7 +856,7 @@ static void __init amd_detect_cmp(struct /* Low order bits define the core id (index of core in socket) */ cpu_core_id[cpu] = phys_proc_id[cpu] & ((1 << bits)-1); /* Convert the APIC ID into the socket ID */ - phys_proc_id[cpu] >>= bits; + phys_proc_id[cpu] = phys_pkg_id(bits); #ifdef CONFIG_NUMA node = phys_proc_id[cpu]; - : send the line "unsubscribe linux-x86_64" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
