Date:   Fri, 24 Feb 2023 21:40:46 +0000
From:   David Woodhouse <dwmw2@infradead.org>
To:     Brian Gerst <brgerst@gmail.com>,
        Usama Arif <usama.arif@bytedance.com>
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>
Subject: =?US-ASCII?Q?Re=3A_=5BExternal=5D_=5BPATCH_v2_0/5=5D_x86-6?= =?US-ASCII?Q?4=3A_Remove_global_variables_from_boot?=
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On 24 February 2023 21:38:41 GMT, Brian Gerst <brgerst@gmail=2Ecom> wrote:
>On Fri, Feb 24, 2023 at 3:40 PM Usama Arif <usama=2Earif@bytedance=2Ecom>=
 wrote:
>>
>>
>>
>> On 24/02/2023 15:42, Brian Gerst wrote:
>> > This is based on the parallel boot v11 series=2E
>> >
>> > Remove the global variables initial_gs, initial_stack, and
>> > early_gdt_descr from the 64-bit boot code=2E  The stack, GDT, and GSB=
ASE
>> > can be determined from the CPU number=2E
>> >
>> > v2: - Dropped first two patches which were merged into another patch =
in
>> >        the parallel boot series=2E
>> >      - Fixed a compile error in patch 1 found by the kernel test robo=
t=2E
>> >      - Split out the removal of STARTUP_SECONDARY into a separate pat=
ch
>> >        and renumber the remaining flags=2E
>> >
>> > Brian Gerst (5):
>> >    x86/smpboot: Remove initial_stack on 64-bit
>> >    x86/smpboot: Remove early_gdt_descr on 64-bit
>> >    x86/smpboot: Remove initial_gs
>> >    x86/smpboot: Simplify boot CPU setup
>> >    x86/smpboot: Remove STARTUP_SECONDARY
>> >
>> >   arch/x86/include/asm/processor=2Eh |  6 +-
>> >   arch/x86/include/asm/realmode=2Eh  |  1 -
>> >   arch/x86/include/asm/smp=2Eh       |  5 +-
>> >   arch/x86/kernel/acpi/sleep=2Ec     |  5 +-
>> >   arch/x86/kernel/head_64=2ES        | 99 ++++++++++++---------------=
-----
>> >   arch/x86/kernel/smpboot=2Ec        |  6 +-
>> >   arch/x86/xen/xen-head=2ES          |  2 +-
>> >   7 files changed, 49 insertions(+), 75 deletions(-)
>> >
>>
>> Its weird putting something in earlier patches like
>> STARTUP_APICID_CPUID_*,STARTUP_SECONDARY=2E=2E and removing/changing it
>> later on in *the same series*=2E Maybe better to keep this as a separat=
e
>> series from parallel smp? i=2Ee=2E not include this in v12 and review i=
t
>> separately? Happy with whatever you and David decide=2E=2E
>>
>> Thanks,
>> Usama
>
>Removing the globals before the parallel boot series, would be the
>best option IMO=2E  That would make the transition simpler=2E

Yeah, makes sense=2E=2E Let's do that=2E