On 07.10.2013 16:05, Erik Faye-Lund wrote: > On Mon, Oct 7, 2013 at 2:52 PM, Terje Bergström <tbergstrom@xxxxxxxxxx> wrote: >> AND 0xff is necessary, because the same registers are mirrored in >> multiple contexts. AND removes the offset coming from context, and >> leaves just the plain register offset. > The offsets in the commands don't have enough bits to reach over to > the next context. The contexts are repeated at multiples of 0x4000, > and 0xFFF is the largest encodable offset. So I don't really thing the > AND is needed for *that* purpose. Well, that was embarrassing. Of course that is true. You can access all registers via MMIO or with SETCLASS to correct context. But that was still the reason I used when I wrote that 0xff, so it's bogus. Real fix is to do what Thierry already did: limit the bitmap to max register number we're interested in, and have a if() to fail fast if register number falls outside that range. Even better, get IOMMU up and running. Terje _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/dri-devel