Message-ID: <304d9fc1-3fe2-a941-7b56-532f8acea049@bytedance.com>
Date:   Thu, 23 Feb 2023 19:14:51 +0000
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Subject: Re: [External] Re: [PATCH 0/6] x86-64: Remove global variables from
 boot
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To:     Brian Gerst <brgerst@gmail.com>,
        David Woodhouse <dwmw2@infradead.org>
Cc:     linux-kernel@vger.kernel.org, x86@kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Borislav Petkov <bp@alien8.de>,
        "H . Peter Anvin" <hpa@zytor.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Andy Lutomirski <luto@kernel.org>,
        Ingo Molnar <mingo@kernel.org>
References: <20230222221301.245890-1-brgerst@gmail.com>
 <5bc62f30a439345eaf58231bafe621b28c62d85e.camel@infradead.org>
 <CAMzpN2j7-GV4ONG7P-R6fZ3P+ZYu9CRzZYFbO+OswX+XZwV4nA@mail.gmail.com>
From:   Usama Arif <usama.arif@bytedance.com>
In-Reply-To: <CAMzpN2j7-GV4ONG7P-R6fZ3P+ZYu9CRzZYFbO+OswX+XZwV4nA@mail.gmail.com>
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On 23/02/2023 14:24, Brian Gerst wrote:
> On Thu, Feb 23, 2023 at 8:44 AM David Woodhouse <dwmw2@infradead.org> wrote:
>>
>> On Wed, 2023-02-22 at 17:12 -0500, Brian Gerst wrote:
>>> This is on top of the parallel boot v10 series.
>>>
>>> Remove the global variables initial_gs, initial_stack, and
>>> early_gdt_descr from the 64-bit boot code.  The stack, GDT, and GSBASE
>>> can be determined from the CPU number.
>>>
>>> Brian Gerst (6):
>>>    x86/smpboot: Use CPU number instead of APIC ID for single CPU startup
>>>    x86/smpboot: Use current_task to get idle thread
>>
>>
>> I think those first two should be folded into the 'x86/smpboot: Support
>> parallel startup of secondary CPUs' patch rather than follow-on
>> patches?
> 
> Yes, that makes sense.
> 
>>>    x86/smpboot: Remove initial_stack on 64-bit
>>>    x86/smpbppt: Remove early_gdt_descr on 64-bit
>>>    x86/smpboot: Remove initial_gs
>>>    x86/smpboot: Simplify boot CPU setup
>>
>> Those four probably make sense to come separately. For each of them,
>>
>> Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>
>>
>> I've pulled in the v10 series from Usama, squashed the first two as I
>> suggested, added the last four on top to do some testing:
>> https://git.infradead.org/users/dwmw2/linux.git/shortlog/refs/heads/parallel-6.2-rc8-part1
> 
> Looks good.  I noticed a typo in the commit log of the last patch
> (dynammically -> dynamically).  Can you fix that or should I resend?
> 
> Thanks
> 
> --
> Brian Gerst

I have tested the branch on top of v6.2 release and sent it as v11. Have 
also fixed the typo.

Thanks,
Usama