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

From: Thomas Gleixner
Date: Thu Nov 10 2016 - 06:16:43 EST


On Thu, 10 Nov 2016, Charles (Chas) Williams wrote:
> 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?

That's right. Looking into it ....