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 Benchmarking Platform
Phoromatic Test Orchestration

Intel's GEM-Free UMS Driver Still Doesn't Fix Things

Intel

Published on 08 August 2010 11:02 PM EDT
Written by Michael Larabel in Intel
6 Comments

Towards the end of last month we reported on GEM-free UMS support for the Intel driver that was worked on by Intel's Chris Wilson to hopefully address the stability issues and other problems that have challenged owners of old Intel i8xx hardware running the newer Intel driver stack, which is presently limited to kernel mode-setting support with GEM (the Graphics Execution Manager) memory management. However, it seems the work invested into adding back user-space mode-setting support to the Intel driver without the kernel memory management still doesn't resolve the i8xx issues at hand.

Once Intel had pushed the Graphics Execution Manager into the mainline Linux kernel followed by the kernel mode-setting (KMS) infrastructure, they were very quick to kill off their EXA 2D acceleration and user-space mode-setting driver support in favor of their GEM-using UXA acceleration and kernel-space mode-setting, respectively. Intel's open-source driver stack originally had some nasty regressions following this invasive work, but Intel's newest stack is fairly stable and on-par with their older code -- unless you happen to be using an older i8xx series chipset where the support has fallen behind and is really no longer a focus of Intel or that of most distribution vendors.

Chris Wilson worked on adding back a GEM-free UMS code-path for those older Intel customers (though it should also work with newer Intel chipsets too) in hopes that this would take care of the stability and freezing problems that has become a common occurrence to those using the newer driver stack such as what's found in recent distributions like Ubuntu 10.04 LTS. This work hasn't yet been pushed into the mainline xf86-video-intel DDX driver, but it has been packaged for Ubuntu in a PPA and Ubuntu developers have encouraged those with Intel hardware to try this driver. A few weeks have passed since this call-for-testing and the results seem to be mixed.

With the UMS driver, one user reported X freezing with a blank screen on boot using an i855GM chipset. With the mainline driver and its kernel mode-setting paths, the X Server boots and works for this user until it comes time to use X-Video, at which point it freezes. Another user also with an i855GM is able to start the X.Org server properly, but when attempting video playback the system will crash and result in a black screen.

Some users, such as one with a Brookdale 845G chipset has been using this UMS driver for multiple days without issues. Another i845G owner running Ubuntu 10.04 LTS has suffered an unresponsive black screen when starting the X.Org Server with this yet-to-be-mainlined driver. Someone that had tested out this UMS driver with a newer Intel 945GM IGP reported no apparent regressions. The last person to report i8xx problems was this evening and for her the driver from Chris Wilson had resulted in the system locking up in less than 20 minutes.

While this driver work is doing good for some i8xx users, it's not helping out everyone or even most users, which puts this reintroduced UMS support into question and perhaps will not even make it into Intel's mainline X.Org driver. Next month at the X Developers' Summit in Toulouse they may just decide to kill it with fire and recommend users of this vintage Intel hardware to stick to a more dated driver / distribution.

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 Articles & Reviews
  1. Sub-$20 802.11n USB WiFi Adapter That's Linux Friendly
  2. The Lenovo T450s Is Working Beautifully With Linux
  3. Linux 4.0 SSD EXT4 / Btrfs / XFS / F2FS Benchmarks
  4. Linux 4.0 Hard Drive Comparison With Six File-Systems
  5. Lenovo ThinkPad T450s Broadwell Preview
  6. How Open-Source Allowed Valve To Implement VULKAN Much Faster On The Source 2 Engine
Latest Linux News
  1. Library Operating System (LibOS) For Linux Still Being Pursued
  2. C4 Game Engine Continues Supporting Linux
  3. Debian 8.0 Jessie's Installer RC3 Released
  4. Features Thus Far For The Linux 4.1 Kernel
  5. Intel's Turbostat Adds Skylake Support In Linux 4.1
  6. Microsoft's Open-Source Group Merges Back Into The Company
  7. EXT4 In Linux 4.1 Adds File-System Level Encryption
  8. Open-Source Ardour 4.0 Audio Software Has Big Improvements
  9. Linux-Powered Endless Computer Raises $100k+ In A Few Days
  10. GCC 5.1 RC2 Arrives, GCC 5.1 Planned For Next Week
Most Viewed News This Week
  1. Nouveau: NVIDIA's New Hardware Is "VERY Open-Source Unfriendly"
  2. Linux 4.1 Brings Many Potentially Risky x86/ASM Changes
  3. Linux 4.0 Kernel Released
  4. Microsoft Announces An LLVM-Based Compiler For .NET
  5. VirtualBox 5.0 Beta 2 Released
  6. KDBUS Is Taking A Lot Of Heat, Might Be Delayed From Mainline Linux Kernel
  7. LibreOffice 4.5 Bumped To Become LibreOffice 5.0
  8. Linux Audio Is Being Further Modernized With The 4.1 Kernel