Andrew Morton <[EMAIL PROTECTED]> writes: > So is this a for-2.6.20 thing? The bug was present in 2.6.19, so > I assume it doesn't affect many people?
If it's not to late, and this patch isn't too scary. It's a really rare set of circumstances that trigger it, but the possibility of being hit is pretty widespread, anything with more than one cpu, and more then one irq could see this. The easiest way to trigger this is to have two level triggered irqs on two different cpus using the same vector. In that case if one acks it's irq while the other irq is migrating to a different cpu 2.6.19 get completely confused and stop handling interrupts properly. With my previous bug fix (not to drop the ack when we are confused) the machine will stay up, and that is obviously correct and can't affect anything else so is probably a candidate for the stable tree. With this fix everything just works. I don't know how often a legitimate case of the exact same irq going off twice in a row is, but that is a possibility as well especially with edge triggered interrupts. Setting up the test scenario was a pain, but by extremely limiting my choice of vectors I was able to confirm I survived several hundred of these events with in a couple of minutes no problem. Eric - 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/
