On Thu, Aug 08, 2013 at 11:28:44AM -0700, Grant Grundler wrote: > I can't speak to the previous BUG_ON(). I believe the EADDRESSINUSE > failures could be either WARN_ON or BUG_ON. This condition is > clearly a bug in the generic IOMMU allocator and I think that's why > KyongHo Cho used BUG_ON. > > Handing out duplicate addresses will generally lead to some sort of > data corruption or other fault depending on how robust the underlying > device drivers are written. So my preference is a BUG_ON to > immediately flag this condition instead of hoping a device driver will > correctly handling the dma mapping failure (Some do, most currently > don't). > > WARN_ON() + return -EADDRESSINUSE would be a good alternative. Even if it is a real BUG condition, I don't think it is worth to stop execution at this point. It makes debugging harder and the system less reliable. I prefer to go with the WARN_ON and an error return value. Joerg -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
