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    SubjectRe: [Fastboot] [PATCH] x86_64: Reload CS when startup_64 is used.
    Hi Eric,

    On 8/22/06, Eric W. Biederman <ebiederm@xmission.com> wrote:
    >
    > In long mode the %cs is largely a relic. However there are a few cases
    > like lret where it matters that we have a valid value. Without this
    > patch it is possible to enter the kernel in startup_64 without setting
    > %cs to a valid value. With this patch we don't care what %cs value
    > we enter the kernel with, so long as the cs shadow register indicates
    > it is a privileged code segment.
    >
    > Thanks to Magnus Damm for finding this problem and posting the
    > first workable patch. I have moved the jump to set %cs down a
    > few instructions so we don't need to take an extra jump. Which
    > keeps the code simpler.
    >
    > Signed-of-by: Eric W. Biederman <ebiederm@xmission.com>

    While at it, could you please fix up the purgatory code in kexec-tools
    to include this fix so we can boot older versions of the kernel too?

    Thanks,

    / magnus
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