Intel's New Clarkdale IGP On Linux Not So Pleasant

Last week we shared that Intel Core i3 Linux benchmarks were being worked on at Phoronix with an Intel Core i3 530 "Clarkdale" processor that we had purchased. This recently released Intel Core i3 processor features an integrated graphics processor on the CPU itself. This next-generation Intel graphics processor is supported by the Linux 2.6.33 DRM and was actually being worked on publicly within the Intel Linux driver stack for months under the name of IGDNG. While Intel has been working on the Linux support for more than six months, the experience is still not ideal.

A daily development build of Ubuntu 10.04 LTS was loaded up on the Intel H55 motherboard we were using for testing in conjunction with the Intel Core i3 530 processor. Ubuntu 10.04 uses the Linux 2.6.32 kernel, Mesa 7.7, and right now is using the older xf86-video-intel 2.9 X.Org driver. Even with the older DDX, the Ubuntu 10.04 live environment started up fine from a USB flash drive. Kernel mode-setting was there and even Compiz was working "out of the box" from the live mode and then once installed to the hard drive.

After installing this Ubuntu 10.04 snapshot everything continued working fine on the desktop with KMS and Compiz. The Phoronix Test Suite was then installed and a few OpenGL benchmarks were carried out. They ran fine. However, with time problems have started to arise. While running some OpenGL programs, the display would simply shut off and no signal was being sent to the monitor. In most cases the system though was still online and could be remotely connected in via SSH. When doing so, many Intel DRM errors were exposed through dmesg. The Intel Clarkdale GPU was getting hung under Linux and seems to originate with its kernel memory management, the Graphics Execution Manager (i915_do_wait_request comes from i915_gem.c).

[ 545.947427] [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
[ 545.947437] render error detected, EIR: 0x00000000
[ 545.947454] [drm:i915_do_wait_request] *ERROR* i915_do_wait_request returns -5 (awaiting 657028 at 657024)
[ 545.947464] [drm:drm_crtc_helper_set_config] *ERROR* failed to set mode on crtc ffff88006e982800
[ 548.197399] [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
[ 548.197407] render error detected, EIR: 0x00000000
[ 548.197420] [drm:i915_do_wait_request] *ERROR* i915_do_wait_request returns -5 (awaiting 657033 at 657024)
[ 548.947404] [drm:i915_hangcheck_elapsed] *ERROR* Hangcheck timer elapsed... GPU hung
[ 548.947412] render error detected, EIR: 0x00000000
[ 548.947430] [drm:i915_do_wait_request] *ERROR* i915_do_wait_request returns -5 (awaiting 657036 at 657024)

The Linux kernel on Ubuntu 10.04 was then updated to the latest Linux 2.6.33 code, libdrm was also updated, and then the xf86-video-intel 2.10 DDX (the latest release with official Clarkdale / Arrandale support) was installed. These GPU hangs continue to occur and in some cases even more frequently than using the slightly older driver stack. So far these GPU hangs is the most common problem we have encountered with this new Intel on-CPU graphics processor, which results in the need for a reboot and then hoping that when it reboots the OpenGL benchmark will run without crashing. Within the next week or two an article will be on Phoronix with our formal findings as well as the first Linux benchmarks from the graphics processor found on the Intel Clarkdale / Core i3 processor.