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    SubjectRe: [GIT PULL] x86 setup BIOS workarounds

    > + /* ACPI 3.0 added the extended flags support. If bit 0
    > + in the extended flags is zero, we're supposed to simply
    > + ignore the entry -- a backwards incompatible change! */
    > + if (size > 20 && !(buf.ext_flags & 1))
    > + continue;

    At the risk of rushing to the defense of the ACPI spec...

    This does not look like a backwards incompatible change to me.

    In ACPI 2.0, size of 20 is always returned, and it would
    be a Linux bug if we examined the undefined values after byte 19.

    In ACPI 3.0, byte 20 is now defined. So if the BIOS returns
    a size >= 21, we are permitted to examine byte 20.

    So I agree with the test above, but I do not agree with the comment.

    Len Brown, Intel Open Source Technology Center

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