Created attachment 275827 [details]
Call trace of crash decoded with decode_stacktrace.sh
kernel: BUG: unable to handle kernel NULL pointer dereference at 00000000000002e4
This happens multiple times a day on my machine. It leads to a complete system freeze. Yesterday I was lucky and got a stack trace.
It mostly happens browsing the web with Firefox (WebRender enabled, XWayland, Gnome-Shell) when the cursor moves or rotates. But it can happen anywhere and anytime.
The used kernel is from branch drm-next-4.18-wip@92fb374 of Alex Deucher, AMD (agd5f). See: git://people.freedesktop.org/~agd5f/linux.
* Hardware name: Acer Swift SF315-41/Becks_RR, BIOS V1.04 01/09/2018
* Ryzen Mobile 2500U
* Firmware: VCN: 1.73 (latest available version)
* My kernel is tainted because the i2c designware driver emits a warning during
boot. This should be unrelated to AMDGPU
(see attachment i2c_designware_trace.txt).
Please ask if anything else is needed.
Created attachment 275829 [details]
Original call trace of crash
Created attachment 275831 [details]
Journal log with amdgpu.dc_log=1 drm.debug=6
Created attachment 275833 [details]
Call trace of i2c designware warning (taints kernel)
I have almost exactly the same hardware but the Ryzen 7 (2700U) version. I also get multiple daily freezes. Many thanks for the additional info, I never managed to get any. I did try kdump but it never triggers, even when forcing a kernel panic. I'm now running OpenSUSE 15.0 with kernels from the "stable" repository (currently 4.16.12-1.g39c7522) and recent Mesa 18.2 prerelease builds.
After seeing amdgpu.vm_update_mode=3 mentioned in bug #199749, I tried it but it didn't help.
Those two are unrelated bugs.
I had high hopes for 4.18-rc1 but alas it froze after a few hours. :( I know having the latest firmware is important so I have that too. These OpenSUSE packages (some unofficial) are installed:
OP also filed a freedesktop.org bug report with more information.
Still the same with 4.18-rc4. :(
From the freedesktop.org bug:
It seems to me that this is in fact a CPU related problem. Since July 25 I don’t have any problems. My system is pretty stable. What helped was to add idle=nomwait to my GRUB command line. This has fixed those problems for me.
Please try to add idle=nomwait to your GRUB command line. I think this bug can be closed.
I added idle=nomwait recently and that has fixed it for me too. I thought I had already tried this, not sure, but perhaps there were two issues and the other has since been fixed.
See comment #9 and #10. Kernel parameter idle=nomwait fixed this bug for me. It seems to be a CPU related problem.