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    SubjectRe: [BUG] x86 kenel won't boot under Virtual PC
    > Btw, I do think that the whole NOPL issue is separate from all the other 
    > issues. There can be _other_ cases where it really is worth doing some
    > "generic" optimizations or being more "specific", and my argument really
    > is that NOPL is _not_ one of those cases.
    >
    > So I'm still not sure that X86_GENERIC is necessarily the answer. The

    FWIW I personally think Linux should always use very conservative nops.
    Unconditionally. This issue already cost far too much developer time
    and it's unlikely to be worth it.

    > Peter - does gcc actually use NOPL in _32-bit_ code too? It really seems

    gcc just uses .p2align, so it comes down to binutils

    Yes there seems to be a pretty scary ISA selection code in there.

    Line 565 of

    http://www.google.com/codesearch?hl=en&q=i386_align_code+show:pxieOi43ptA:OXGjJbna8V8:zfd_fdPYgEI&sa=N&cd=1&ct=rc&cs_p=http://gentoo.osuosl.org/distfiles/binutils-2.17.50.0.13.tar.bz2&cs_f=binutils-2.17.50.0.13/gas/config/tc-i386.c

    I haven't decoded it completely, but I suspect it does the wrong thing.

    -Andi


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