Comments (1)

By Matthieu, 2019-04-29 09:55

Update: Even after doing all this the system still locks up randomly when using the amdgpu driver.

I’m running dual AMD FirePro W2100 driving 3 monitors in my workstation. Since installing the cards I’ve been suffering random freezes/graphical lockups that seemed to be related to 3D. They occurred typically during an animation in gnome-shell, or when using Firefox or Chrome with hardware acceleration. Most times, I was able to recover by logging in to the machine via ssh and sending killall -HUP to the appropriate process (usually gnome-shell). Every time this happened, syslog would be full of GPU faults:

[ 2482.763707] radeon 0000:02:00.0: GPU fault detected: 146 0x0468100c
[ 2482.763708] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_ADDR   0x0011173E
[ 2482.763709] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x0805000C
[ 2482.763710] VM fault (0x0c, vmid 4) at page 1120062, read from CB (80)
[ 2482.763713] radeon 0000:02:00.0: GPU fault detected: 146 0x0408500c
[ 2482.763714] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_ADDR   0x00111744
[ 2482.763715] radeon 0000:02:00.0:   VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x0805000C
[ 2482.763717] VM fault (0x0c, vmid 4) at page 1120068, read from CB (80)

I tried updating my kernel (going from Ubuntu 18.04 to 18.10 and even reinstalling with Pop!_OS 18.10 than 19.04) and updating graphics drivers using the oibaf ppa, to no avail. Finally found what seems to be the solution on HackerNews (thanks danieldk) – force the use of the newer amdgpu driver rather than the older radeon driver. The W2100 is a first-generation GCN chip and so is supported by both drivers, and radeon is chosen as the default. To force amdgpu, you need to pass the kernel flags

amdgpu.si_support=1 radeon.si_support=0 amdgpu.cik_support=1 radeon.ciksupport=0

In Ubuntu, add these to GRUB_CMDLINE_LINUX_DEFAULT in /etc/default/grub, then run update_grub. Pop!_OS doesn’t use grub, so you need to add each flag using kernelstub -a amdgpu.si_support=1 and repeating for each of the 4.

So far, my system seems stable since this change. I will update this post if anything changes.

Comments (5)

By Matthieu, 2011-06-23 21:40

Update: Just went and exchanged the HD 6450 for an HD 6670. This one works great, runs Starcraft II on High and doesn’t crash the machine!

After some discussion with a coworker, I decided to try putting a Sapphire Radeon HD6450 into my Mac Pro, since the 8800GT was a real power hog and heater.

Just my luck that today the 10.6.8 update was released, containing – you guessed it – HD6xxx drivers!

So I ran the update, then popped in the HD6450, and what do you know, it works! Only two problems: First, no EFI support which means no boot screen (white/grey apple). Second, it seems to crash when launching any game. I tried Lord of the Rings: Return of the King and Starcraft II, and both caused the screen to go blank and kernel panic.

Anyway, nice experiment, and at least it works for regular desktop work….

For anyone interested, here are all the Radeon HD6000 series cards supported by the 10.6.8 kexts, IDs and names.

• 0x67681002  CAICOS 6450M
• 0x67701002  NI CAICOS [AMD Radeon HD 6400 Series]
• 0x67791002  NI Caicos [AMD RADEON HD 6450]
• 0x67601002  NI Seymour [AMD Radeon HD 6470M]
• 0x67611002  NI Seymour [AMD Radeon HD 6430M]
• 0x67501002  Turks [AMD Radeon HD 6500 series]
• 0x67581002  Turks XT [AMD Radeon HD 6600 Series]
• 0x67591002  NI Turks [AMD Radeon HD 6500]
• 0x67401002  Whistler XT [AMD Radeon HD 6700M Series]
• 0x67411002  NI Whistler [AMD Radeon HD 6600M Series]
• 0x67381002  Barts XT [ATI Radeon HD 6800 Series]
• 0x67391002  Barts PRO [ATI Radeon HD 6800 Series]
• 0x67201002  Blackcomb [AMD Radeon HD 6900M Series]
• 0x67221002 ATI Radeon HD 6950
• 0x67181002  Cayman XT [AMD Radeon HD 6900 Series]