On Wed, Dec 7, 2016 at 4:57 AM, Alexandre Courbot <gnurou@xxxxxxxxx> wrote: > On Wed, Dec 7, 2016 at 6:53 PM, Michel Dänzer <michel@xxxxxxxxxxx> wrote: >> On 07/12/16 06:39 PM, Alexandre Courbot wrote: >>> On Fri, Dec 2, 2016 at 12:23 PM, Ilia Mirkin <imirkin@xxxxxxxxxxxx> wrote: >>>> That's right -- nouveau currently requires 4k page sizes to work. This is a >>>> software limitation, not a hardware one though. >>> >>> Looking at the trace I wonder - is the limitation in Nouveau or in TTM? >> >> Nouveau. Non-4K page sizes work fine with radeon (and presumably amdgpu). > > Thanks for the precision. I will check if Tegra iGPUs are also > affected by this - if they are then it gives me a good excuse to take > care of this bug. For the most part it's confusion in the (nouveau) code as to what's a gpu page and what's a cpu page (and the shifts involved). There are some fringe issues that will need to be addressed, like the fact that it's no longer a 1:1 mapping, which might be assumed in some places. However I thought that 64K-pages were frowned upon nowadays for the kernel - outside of HPC loads, most of the kernel memory becomes pagecache, and files don't tend to be 64K-sized, so you have tons of wasted memory (since you never cache multiple files in the same page). But don't take that as me disapproving of such a project. It'd esp be nice to do something like this outside of the PPC64 environment, where BE concerns mix in with the 64K page concerns, and nothing works as a result. -ilia _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel
