Someone willing to take a look? On Fri, Oct 02, 2015 at 06:51:59AM +0800, Wei Yang wrote: >On Thu, Oct 01, 2015 at 02:15:45PM +1000, Michael Ellerman wrote: >>On Thu, 2015-10-01 at 07:50 +0800, Wei Yang wrote: >>> Hmm... some comments on this one? like it or not? >> >>It sounds like it's fixing a bug, but you don't really say. Have you seen this >>fail in the wild? > >Hmm... as described in the commit log, this would be a bug when >PAGE_SIZE is much smaller than IOMMU Page Size. This configuration doesn't >happen on current platform. So I didn't see this failure yet. > >> >>Which commit introduced the breakage? > >Hmm... maybe we could say it is 'commit d084775738b7 ><powerpc/iommu: Update the generic code to use dynamic iommu page sizes>'. >>From this commit, powerpc iommu supports dynamic iommu page size. > >Before this commit, the size is aligned with PAGE_SIZE, so the value after >shift would be non-zero. After this commit, when PAGE_SIZE is smaller than >the IOMMU Page Size, shift right will make the size 0. > >> >>cheers >> > >-- >Richard Yang >Help you, Help me
-- Richard Yang Help you, Help me _______________________________________________ Linuxppc-dev mailing list [email protected] https://lists.ozlabs.org/listinfo/linuxppc-dev
