MIME-Version: 1.0
Date:   Tue, 21 Feb 2023 09:44:53 +0100
From:   Oleksandr Natalenko <oleksandr@natalenko.name>
To:     David Woodhouse <dwmw2@infradead.org>
Cc:     Kim Phillips <kim.phillips@amd.com>, tglx@linutronix.de,
        Usama Arif <usama.arif@bytedance.com>, arjan@linux.intel.com,
        mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com,
        hpa@zytor.com, x86@kernel.org, pbonzini@redhat.com,
        paulmck@kernel.org, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, rcu@vger.kernel.org, mimoja@mimoja.de,
        hewenliang4@huawei.com, thomas.lendacky@amd.com, seanjc@google.com,
        pmenzel@molgen.mpg.de, fam.zheng@bytedance.com,
        punit.agrawal@bytedance.com, simon.evans@bytedance.com,
        liangma@liangbit.com,
        "Limonciello, Mario" <Mario.Limonciello@amd.com>,
        Piotr Gorski <piotrgorski@cachyos.org>
Subject: Re: [PATCH v9 0/8] Parallel CPU bringup for x86_64
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On 21.02.2023 09:35, David Woodhouse wrote:
> On Tue, 2023-02-21 at 09:25 +0100, Oleksandr Natalenko wrote:
>> 
>> 
>> Right, sorry. Here it is: http://ix.io/4oLq
> 
> $ echo `grep ^00000001 4oLq  | cut -c36-37`
> 00 02 04 06 08 0a 0c 0e 10 12 14 16 18 1a 1c 1e 01 03 05 07 09 0b 0d 0f
> 11 13 15 17 19 1b 1d 1f
> 
> Well they look sane enough. All even APIC IDs and then all the odd ones
> is a topology that isn't massively surprising.
> 
> Does it match what you get *before* suspend/resume?

Yes, the output is completely the same after a fresh boot and after a 
suspend/resume cycle.

> Obviously we could stick our fingers in our ears and go "la la la" and
> just disable it for non-X2APIC, for AMD without X2APIC, or perhaps
> disable it on *resume* but still use it at boot. But I'd really like to
> understand what's going on and not do voodoo. Thanks for helping!

-- 
   Oleksandr Natalenko (post-factum)