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    SubjectRe: [PATCH] kdump, vmcoreinfo: Export sme_me_mask value to vmcoreinfo
    On Fri, Oct 26, 2018 at 06:24:40PM +0200, Petr Tesarik wrote:
    > But we need the MSR value from the panic kernel environment, not while
    > the production kernel is still running, right?

    Actually, we need only the encryption bit number (and it should be 0
    otherwise to denote SME wasn't enabled).

    I guess something like

    VMCOREINFO_NUMBER(sme_mask);

    which gets written by the kexec-ed kernel.

    > If so, then this reminds me that I have wanted for a long time to store
    > more of the hardware state in a vmcore NOTE after a kernel crash ...
    > control registers, MSRs and whatnot. Of course, this would be a
    > long-term project, but I wonder what other people think about it in
    > general.

    I guess that sounds like a good idea - the more relevant hw info for
    debugging, the better. Determining the important MSRs to save would need
    a bit of a pondering over though. For example, some MSRs are per-core,
    some per-socket, etc...

    --
    Regards/Gruss,
    Boris.

    ECO tip #101: Trim your mails when you reply.
    --

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