1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Intel & Radeon DRM Drivers Get Last Minute 3.15 Fixes

Linux Kernel

Published on 30 May 2014 08:59 PM EDT
Written by Michael Larabel in Linux Kernel
13 Comments

Fallout from the many changes introduced early on in the Linux 3.15 kernel cycle are almost all addressed and this next kernel release should happen in the very near future. As some last minute work are some notable fixes for the Intel and Radeon DRM graphics drivers.

Among the changes in the latest DRM stable pull are:

- The i915 driver preventing negative relocation deltas from wrapping. "This is pure evil. Userspace, I'm looking at you SNA, repacks batch buffers on the fly after generation as they are being passed to the kernel for execution. These batches also contain self-referenced relocations as a single buffer encompasses the state commands, kernels, vertices and sampler. During generation the buffers are placed at known offsets within the full batch, and then the relocation deltas (as passed to the kernel) are tweaked as the batch is repacked into a smaller buffer. This means that userspace is passing negative relocations deltas, which subsequently wrap to large values if the batch is at a low address. The GPU hangs when it then tries to use the large value as a base for its address offsets, rather than wrapping back to the real value (as one would hope). As the GPU uses positive offsets from the base, we can treat the relocation address as the minimum address read by the GPU. For the upper bound, we trust that userspace will not read beyond the end of the buffer." This fix should take care of the buggy Iris Pro Graphics I've been experiencing.

- A Radeon DRM driver hang fix regarding RADEON_GEM_DOMAIN_CPU for command submission.

- A Radeon PLL workaround.

- A fix for the Radeon DRM driver breaking suspend-and-resume with the new kernel.

More details on the other bug fixes for Linux 3.15-rc8 can be found via the DRM-stable pull request.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. Even With Re-Clocking, Nouveau Remains Behind NVIDIA's Proprietary Linux Driver
  2. The Power Consumption & Efficiency Of Open-Source GPU Drivers
  3. AMD R600g/RadeonSI Performance On Linux 3.16 With Mesa 10.3-devel
  4. Intel Pentium G3258 On Linux
Latest Linux Articles
  1. Nouveau vs. Radeon vs. Intel Tests On Linux 3.16, Mesa 10.3-devel
  2. KVM Benchmarks On Ubuntu 14.10
  3. X.Org Server 1.16 Officially Released With Terrific Features
  4. Ubuntu With Linux 3.16 Smashes OS X 10.9.4 On The MacBook Air
Latest Linux News
  1. Grand Theft Auto Running On Direct3D Natively On Linux Shows Gallium3D Potential
  2. GCC As A Just-In Time Compiler Is An Interesting Project
  3. Age Of Wonders III Is Still Being Ported To Linux
  4. Git 2.1 To Further Mainline Windows Support Patches
  5. Debian 8.0 Jessie Is Settling For Linux 3.16
  6. Meson: A Next-Gen Build System Showing Promise
  7. Linux 3.16-rc7 Calms Things Down For The Linux 3.16 Kernel
  8. Open-Source AMD Users Report Hawaii GPU Acceleration Is Working
  9. Linus Torvalds On GCC 4.9: Pure & Utter Crap
  10. Cauldron 2014: GCC & LLVM Will Look To Collaborate More
Latest Forum Discussions
  1. Linus Torvalds On GCC 4.9: Pure & Utter Crap
  2. Updated and Optimized Ubuntu Free Graphics Drivers
  3. Porting Mesa to the Playstation 2
  4. ASRock AM1H-ITX: One Of The Best AM1 Mini-ITX Motherboards
  5. Debian + radeonsi
  6. Open-source drivers on ATI R7 260X
  7. Table test
  8. How To Setup Radeon DPM On Ubuntu Linux