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    SubjectRe: [RFC] page fault retry with NOPAGE_RETRY
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    On Thu, 2006-09-21 at 15:41 -0700, Andrew Morton wrote:
    > On Fri, 22 Sep 2006 08:05:04 +1000
    > Benjamin Herrenschmidt <benh@kernel.crashing.org> wrote:
    >
    > > > So I think there's a nasty DoS here if we permit infinite retries. But
    > > > it's not just that - there might be other situations under really heavy
    > > > memory pressure where livelocks like this can occur. It's just a general
    > > > robustness-of-implementation issue.
    > >
    > > Got it. Now, changing args to no_page() will be a pretty big task....
    > >
    >
    > Not as big as removing the pt_regs arg from every interrupt handler ;)

    Which is a change I'm not 100% convinced about btw ... I remember
    actually using that in a few occasions... mostly for debugging though.
    Bah, anyway, I suppose we can always have a per-cpu global with the last
    irq pt_regs pointer if really needed for debug.

    > But pretty mechanical. Problem is, I don't think we have our mechanic.

    Yup, we would need to decide what to put in there....

    Ben.


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