On Thu, 2006-09-21 at 15:41 -0700, Andrew Morton wrote: > On Fri, 22 Sep 2006 08:05:04 +1000 > Benjamin Herrenschmidt <[email protected]> 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. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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- [RFC] page fault retry with NOPAGE_RETRY
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