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    SubjectRe: [BUG] long freezes on thinkpad t60

    * Linus Torvalds <torvalds@linux-foundation.org> wrote:

    > No, the cache line arbitration doesn't know anything about "locked" vs
    > "unlocked" instructions (it could, but there really is no point).
    >
    > The real issue is that locked instructions on x86 are serializing,
    > which makes them extremely slow (compared to just a write), and then
    > by being slow they effectively just make the window for another core
    > bigger.
    >
    > IOW, it doesn't "fix" anything, it just hides the bug with timing.

    yeah. I think Linux is i think the only OS on the planet that is using
    the movb trick for unlock, it even triggered a hardware erratum ;) So it
    might surprise some hw makers who might rely on the heuristics that each
    critical section lock and unlock is a LOCK-ed instruction.

    Ingo
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