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    SubjectRe: [PATCH 19/30] panic: Add the panic hypervisor notifier list
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    On 19/05/2022 16:20, Scott Branden wrote:
    > [...]
    >> Hi Scott / Desmond, thanks for the detailed answer! Is this adapter
    >> designed to run in x86 only or you have other architectures' use cases?
    > The adapter may be used in any PCIe design that supports DMA.
    > So it may be possible to run in arm64 servers.
    >>
    >> [...]
    >> With that said, and given this is a lightweight notifier that ideally
    >> should run ASAP, I'd keep this one in the hypervisor list. We can
    >> "adjust" the semantic of this list to include lightweight notifiers that
    >> reset adapters.
    > Sounds the best to keep system operating as tested today.
    >>
    >> With that said, Petr has a point - not always such list is going to be
    >> called before kdump. So, that makes me think in another idea: what if we
    >> have another list, but not on panic path, but instead in the custom
    >> crash_shutdown()? Drivers could add callbacks there that must execute
    >> before kexec/kdump, no matter what.
    > It may be beneficial for some other drivers but for our use we would
    > then need to register for the panic path and the crash_shutdown path.
    > We notify the VK card for 2 purposes: one to stop DMA so memory stop
    > changing during a kdump. And also to get the card into a good state so
    > resets happen cleanly.

    Thanks Scott! With that, I guess it's really better to keep this
    notifier in this hypervisor/early list - I'm planning to do that for V2.
    Unless Petr or somebody has strong feelings against that, of course.

    Cheers,


    Guilherme

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