2nd monitor/gpu crashes system, maybe a kernel bug?
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2nd monitor/gpu crashes system, maybe a kernel bug?
Hello, thanks for reading. I am having trouble getting Arch to work with a 2nd gpu and monitor. If I try to enable the second display, it crashes the system. I have KDE and LXQT desktop environments installed.
As soon as the second monitor is plugged into gpu #2, the screen on monitor #1 goes black, with a mouse cursor that won't move. I am unable to change tty, and it doesn't respond to magic sysrq keys either. Unplugging the monitor does not fix it, and I have to hard reset.
Each gpu works fine on its own, when the other isn't installed, but I can't get them both working together on Arch. Ubuntu handles both gpu's/monitors without any manual configuration so I know it can work.
The only errors I find in the Xorg logs are (EE) AMDGPU(G0): amdgpu_device_initialize failed
and (EE) AMDGPU(0): Failed to make import prime FD as pixmap: 22. But those same errors occur in ubuntu, which is able to use both monitors and gpu's without issue. And I don't see anything in journalctl that looks relevant so I think it's happening so fast no logs are made or written to.
The freezes happen with kernel versions: 5.12.3-arch1-1, 5.12.4-arch1-2. But it DOES NOT happen with LTS kernel 5.10.37-1-lts. Any ideas how I can go about diagnosing exactly? Or getting any more useful information? Any help is appreciated
When you are having problems with a piece of software, don't claim you have found a bug unless you are very, very sure of your ground. Hint: unless you can provide a source-code patch that fixes the problem, or a regression test against a previous version that demonstrates incorrect behavior, you are probably not sure enough. (...)
Remember, there are many other users that are not experiencing your problem. Otherwise you would have learned about it while reading the documentation and searching the Web (you did do that before complaining, didn't you?). This means that very probably it is you who are doing something wrong, not the software.
AFAICT, the Radeon HD 5450 is an entry level ATI/AMD product. ISTR more than a few reports in the not too distant past that FOSS support for it could be better than it is. These are two quite recent ones that I can remember seeing/writing in:
I'm thinking your best help might come from either making a report in Arch's bug tracking system, or asking for help in one of Arch's own forums, unless that's what you've already done.
I have two 5450s, one by Sapphire, the other by XFX. But, I'm not in position to run either of them paired with another, much less along with one as new or expensive as your RX 5700xt gamer. Also, I've yet to make my first Arch installation. Otherwise, I'd try to reproduce. Mine do have foibles not experienced with other GPUs.
The B550-f seems to support at least 3 displays with a suitable CPU selection. Methinks you could sell or trade the RX 5700xt and install a CPU that includes an APU, so that you'd have no need for any second discrete GPU, much less any entry level model. Or, offload, if that's the reason for the 5450, to an APU. IOW, boot the 5450 out of your system.
Thank you for the assistance. Just a note: There is a new kernel not in the lts line now, 5.12.5-arch1-1. I have installed it, and the symptoms persist. The lts kernel continues to work.
On to what you asked, after forcing a lockup and rebooting, I ran the command you suggested. It appears I am experiencing the same or a similar problem described here: https://bugzilla.redhat.com/show_bug.cgi?id=1946312. He appears to be using Fedora, I'm not sure if that's relevant. And he is experiencing this on kernel 5.12.0-0.rc5.180.fc35.x86_64 #1
I have again removed my gpu's and tested them individually and they work on their own. But will not work when both are installed simultaneously (on Arch). I will note though, that while they do both work on the lts kernel, the performance of the radeon 5450 is abysmal compared to when it is installed on its own (or its performance in ubuntu, with both cards installed).
AFAICT, the Radeon HD 5450 is an entry level ATI/AMD product. ISTR more than a few reports in the not too distant past that FOSS support for it could be better than it is. These are two quite recent ones that I can remember seeing/writing in:
I'm thinking your best help might come from either making a report in Arch's bug tracking system, or asking for help in one of Arch's own forums, unless that's what you've already done.
I have two 5450s, one by Sapphire, the other by XFX. But, I'm not in position to run either of them paired with another, much less along with one as new or expensive as your RX 5700xt gamer. Also, I've yet to make my first Arch installation. Otherwise, I'd try to reproduce. Mine do have foibles not experienced with other GPUs.
The B550-f seems to support at least 3 displays with a suitable CPU selection. Methinks you could sell or trade the RX 5700xt and install a CPU that includes an APU, so that you'd have no need for any second discrete GPU, much less any entry level model. Or, offload, if that's the reason for the 5450, to an APU. IOW, boot the 5450 out of your system.
Yes the 5700xt does indeed support more than one display lol. The reason for the second card is for virtualization reasons. I have considered getting an apu, and plan to... once I can get my hands on the latest gen, like an 5700g.
And 95% of the time what I do, I don't care about graphics, which is the reason for the low end gpu, but I do like to throw on a game every now and then.
Interestingly, switching the gpu's in the slots on the motherboard seems to make them play nicely together. Unfortunately, this is not a solution for my situation. The second pcie slot is not gen4 compatible (realistically idk the consequences of this, though my better gpu advertises it is gen4). Also, the IOMMU groupings for the second slot make things more complicated for virtualization.
I just stumbled across a configuration option that stands a chance of helping:
Code:
Option "ReprobeOutputs" "true"
Put it in /etc/X11/xorg.conf itself (create it if absent; absent is highly probable) or in any .conf file that contains a 'Section "Device"' in /etc/X11/xorg.conf.d/. If the ReprobeOutputs option does not seem to help, try switching to a vtty and back, e.g. Ctrl-Alt-F3, Alt-F7, after switching the #2 display on or off.
Just a note: There is a new kernel not in the lts line now, 5.12.5-arch1-1. I have installed it, and the symptoms persist. The lts kernel continues to work.
Are you saying you aren't experiencing any problems with the LTS kernel? Why don't you just stick with that then?
Quote:
Originally Posted by TheEzekielProject
Here is the relevant section of my journal
Thanks, unfortunately it's way beyond me.
All I see is some sort of kernel panic/coredump. It would be interesting to see the journal entries leading up to it. Something must be triggering it.
If both the above is exactly as you say then I would indeed say you should file a bug report against the affected kernel.
Are you saying you aren't experiencing any problems with the LTS kernel? Why don't you just stick with that then?
Partly because I figured if it was a kernel a bug, it looks like a regression, since the LTS kernel works, and because I figured it was kind of a fix it now or later thing lol. The current kernel versions are bound to be the LTS kernel eventually, right? So I figure it's gonna break eventually.
But unfortunately there were issues that I didn't foresee with the motherboard I purchased, so I swapped my motherboard for a different one.
I was intending to setup my system with windows in kvm/qemu, passing through the 5700 xt to Windows. I mistakenly expected to be able to change the boot gpu in the uefi on the B-550-f, but Asus has not implemented this functionality. I emailed their support, and they said the engineers have no plans to implement it. So I switched out my motherboard for one that does allow you to change the boot gpu. The Gigabyte x570 Aorus Pro wifi.
Interestingly, this kernel issue seems to have gone away with an otherwise identical setup. This particular issue is not one of the ones I expected to resolve by switching mobo's.
Thank you both for your help and effort, ondoho and mrmazda
Last edited by TheEzekielProject; 05-24-2021 at 02:22 PM.
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