Re: [PATCH] x86/cpuid: Deal with broken firmware once more

From: Charles (Chas) Williams
Date: Thu Nov 10 2016 - 05:51:30 EST




On 11/09/2016 10:57 PM, M. Vefa Bicakci wrote:
[ 0.002000] mvb: CPU: Physical Processor ID: 0
[ 0.002000] mvb: CPU: Processor Core ID: 0
[ 0.002000] mvb: identify_cpu:1112: c: ffff880013b0a040, c->logical_proc_id: 65535
[ 0.002000] mvb: __default_cpu_present_to_apicid:612: Returning 65535! mps_cpu: 1, nr_cpu_ids: 2, cpu_present(mps_cpu): 1
[ 0.002000] smpboot: mvb: topology_update_package_map:270: cpu: 1, pkg: 4095
[ 0.002000] smpboot: APIC(ffff) Converting physical 4095 to logical package 0
[ 0.002000] smpboot: mvb: topology_update_package_map:305: cpu: 1, cpu_data(cpu).logical_proc_id: 0

This seems strange. 0xffff is BAD_APICID. Why didn't this fail here:

for_each_present_cpu(cpu) {
unsigned int apicid = apic->cpu_present_to_apicid(cpu);

if (apicid == BAD_APICID || !apic->apic_id_valid(apicid)) <<<<<<<<<<
continue;
if (!topology_update_package_map(apicid, cpu))
continue;

topology_update_package_map() should never have been called?