From: "Charles (Chas) Williams" <ciwillia@brocade.com>
To: Boris Ostrovsky <boris.ostrovsky@oracle.com>,
Thomas Gleixner <tglx@linutronix.de>,
"M. Vefa Bicakci" <m.v.b@runbox.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
"x86@kernel.org" <x86@kernel.org>,
LKML <linux-kernel@vger.kernel.org>,
Peter Zijlstra <peterz@infradead.org>,
Borislav Petkov <bp@alien8.de>,
David Vrabel <david.vrabel@citrix.com>,
Juergen Gross <jgross@suse.com>
Subject: Re: [PATCH] x86/cpuid: Deal with broken firmware once more
Date: Thu, 10 Nov 2016 10:05:01 -0500 [thread overview]
Message-ID: <eecbbfdf-38c1-acdd-402b-3be48cf5fdb7@brocade.com> (raw)
In-Reply-To: <b5f6e797-580b-3c16-c89c-ec16cce084c5@oracle.com>
On 11/10/2016 09:02 AM, Boris Ostrovsky wrote:
> On 11/10/2016 06:13 AM, Thomas Gleixner wrote:
>> On Thu, 10 Nov 2016, M. Vefa Bicakci wrote:
>>
>>> I have found that your patch unfortunately does not improve the situation
>>> for me. Here is an excerpt obtained from the dmesg of a kernel compiled
>>> with this patch *as well as* Sebastian's patch:
>>> [ 0.002561] CPU: Physical Processor ID: 0
>>> [ 0.002566] CPU: Processor Core ID: 0
>>> [ 0.002572] [Firmware Bug]: CPU0: APIC id mismatch. Firmware: ffff CPUID: 2
>> So apic->cpu_present_to_apicid() gives us a completely bogus APIC id which
>> translates to a bogus package id. And looking at the XEN code:
>>
>> xen_pv_apic.cpu_present_to_apicid = xen_cpu_present_to_apicid,
>>
>> and xen_cpu_present_to_apicid does:
>>
>> static int xen_cpu_present_to_apicid(int cpu)
>> {
>> if (cpu_present(cpu))
>> return xen_get_apic_id(xen_apic_read(APIC_ID));
>> else
>> return BAD_APICID;
>> }
>>
>> So independent of which present CPU we query we get just some random
>> information, in the above case we get BAD_APICID from xen_apic_read() not
>> from the else path as this CPU _IS_ present.
>>
>> What's so wrong with storing the fricking firmware supplied APICid as
>> everybody else does and report it back when queried?
>
> By firmware you mean ACPI? It is most likely not available to PV guests.
> How about returning cpu_data(cpu).initial_apicid?
>
> And what was the original problem?
The original issue I found was that VMware was returning a different set
of APIC id's in the ACPI tables than what it advertised on the CPU's.
http://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1266716.html
>>
>> This damned attitude of we just hack the code into submission and let
>> everybody else deal with the outcoming is utterly annoying.
>>
>> Thanks,
>>
>> tglx
>
>
next prev parent reply other threads:[~2016-11-10 15:07 UTC|newest]
Thread overview: 43+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-11-02 12:25 [RFC PATCH] perf/x86/intel/rapl: avoid access unallocate memory Sebastian Andrzej Siewior
2016-11-02 22:47 ` Charles (Chas) Williams
2016-11-03 17:47 ` Sebastian Andrzej Siewior
2016-11-04 12:20 ` Charles (Chas) Williams
2016-11-04 18:03 ` Sebastian Andrzej Siewior
2016-11-04 20:42 ` Charles (Chas) Williams
2016-11-04 20:57 ` Sebastian Andrzej Siewior
2016-11-07 16:19 ` Thomas Gleixner
2016-11-07 16:59 ` Charles (Chas) Williams
2016-11-07 20:20 ` Thomas Gleixner
2016-11-08 14:20 ` Charles (Chas) Williams
2016-11-08 14:31 ` Thomas Gleixner
2016-11-08 14:57 ` Charles (Chas) Williams
2016-11-08 16:22 ` Thomas Gleixner
2016-11-09 15:35 ` [PATCH] x86/cpuid: Deal with broken firmware once more Thomas Gleixner
2016-11-09 15:37 ` Thomas Gleixner
2016-11-09 16:03 ` Peter Zijlstra
2016-11-09 16:34 ` Charles (Chas) Williams
2016-11-09 18:37 ` Thomas Gleixner
2016-11-09 18:15 ` Charles (Chas) Williams
2016-11-09 20:27 ` [tip:x86/urgent] x86/cpu: Deal with broken firmware (VMWare/XEN) tip-bot for Thomas Gleixner
2016-11-11 5:49 ` Alok Kataria
2016-11-10 3:57 ` [PATCH] x86/cpuid: Deal with broken firmware once more M. Vefa Bicakci
2016-11-10 10:50 ` Charles (Chas) Williams
2016-11-10 11:14 ` Thomas Gleixner
2016-11-12 22:05 ` M. Vefa Bicakci
2016-11-10 11:13 ` Thomas Gleixner
2016-11-10 11:39 ` Peter Zijlstra
2016-11-10 14:02 ` Boris Ostrovsky
2016-11-10 15:05 ` Charles (Chas) Williams [this message]
2016-11-10 15:31 ` Boris Ostrovsky
2016-11-10 15:54 ` Sebastian Andrzej Siewior
2016-11-10 17:15 ` Thomas Gleixner
2016-11-12 22:05 ` M. Vefa Bicakci
2016-11-13 18:04 ` Boris Ostrovsky
2016-11-13 23:42 ` M. Vefa Bicakci
2016-11-15 1:21 ` Boris Ostrovsky
2016-11-18 11:16 ` Thomas Gleixner
2016-11-18 14:22 ` Boris Ostrovsky
2016-11-10 15:12 ` Thomas Gleixner
2016-11-10 15:38 ` Boris Ostrovsky
2016-11-10 17:13 ` Thomas Gleixner
2016-11-10 18:01 ` Boris Ostrovsky
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=eecbbfdf-38c1-acdd-402b-3be48cf5fdb7@brocade.com \
--to=ciwillia@brocade.com \
--cc=bigeasy@linutronix.de \
--cc=boris.ostrovsky@oracle.com \
--cc=bp@alien8.de \
--cc=david.vrabel@citrix.com \
--cc=jgross@suse.com \
--cc=linux-kernel@vger.kernel.org \
--cc=m.v.b@runbox.com \
--cc=peterz@infradead.org \
--cc=tglx@linutronix.de \
--cc=x86@kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).