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    SubjectRe: [tip: x86/boot] x86/boot: Ignore NMIs during very early boot
    Hi Zeng Heng,

    On Wed, Apr 03, 2024 at 02:32:45PM +0800, Zeng Heng wrote:
    > Until just now, I saw your completely different responses to the same patch.

    Lemme explain how I see the situation.

    You sent a patch:

    https://lore.kernel.org/all/20230110102745.2514694-1-zengheng4@huawei.com/

    which had a commit message which tried to explain what happens. And
    I tried to parse your commit message and understand what you're trying
    to do but there never was a clear explanation.

    When I read "If kdump is enabled, when using mce_inject to inject
    errors..." then I think, oh great, more experiments. ;-\

    And no, I don't want to add code to early boot just to make some weird
    experiments happy.

    Yeah yeah, an MCE can happen very early but until a real reproducer, I'm
    not convinced.

    Now that other patch's commit message has at least a bit more clear
    explanation how you can *actually* cause this. And I still would've
    asked how *exactly* this happens but it is kinda clear: you can run perf
    and generate an NMI storm and then have two back-to-back NMIs.

    And I'm still not crazy about having an empty early NMI handler either
    thus I suggested to make it at least say something so that we're aware
    that early NMIs have happened.

    So if it is not clear *why* a patch is being done, then it goes nowhere.
    Because you'll go your merry way and "develop driver software based on
    arm64 features" or whatever else you get to do but the maintainers will
    be left to be dealing with your code indefinitely.

    I hope this makes it more clear.

    Thx.

    --
    Regards/Gruss,
    Boris.

    https://people.kernel.org/tglx/notes-about-netiquette

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