I am running on arch linux: Linux arch 5.2.13-arch1-1-ARCH #1 SMP PREEMPT Fri Sep 6 17:52:33 UTC 2019 x86_64 GNU/Linux

I am running wayland via sway.

My gpu is a Radeon RX Vega 64.

While in my sway session the image on my screen froze but audio from a video continued to play. I was able to ssh in from a different machine and found this message with dmesg:

BUG: kernel NULL pointer dereference, address: 0000000000000360
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0
Oops: 0002 [#1] PREEMPT SMP PTI
CPU: 1 PID: 12766 Comm: kworker/u16:0 Not tainted 5.2.11-arch1-1-ARCH #1
Hardware name: ASUS All Series/Z87-PLUS, BIOS 2103 08/15/2014
Workqueue: events_unbound commit_work [drm_kms_helper]
RIP: 0010:dc_stream_retain+0x5/0x20 [amdgpu]
<Code and registers omitted. Can post if important and someone reassures me that it doesn't sensitive information since it looks like a memory dump.>
Call Trace:
 dc_resource_state_copy_construct+0xa0/0xf0 [amdgpu]
 dc_commit_updates_for_stream+0xa63/0xc20 [amdgpu]
 amdgpu_dm_atomic_commit_tail+0xabe/0x19a0 [amdgpu]
 ? commit_tail+0x3c/0x70 [drm_kms_helper]
 commit_tail+0x3c/0x70 [drm_kms_helper]
 process_one_work+0x1d1/0x3e0
 worker_thread+0x4a/0x3d0
 kthread+0xfb/0x130
 ? process_one_work+0x3e0/0x3e0
 ? kthread_park+0x80/0x80
 ret_from_fork+0x35/0x40
Modules linked in: snd_seq_dummy snd_seq tun nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 libcrc32c nf_tables_set cfg80211 nf_tables nfnetlink 8021q garp mrp stp llc intel_rapl nls_iso8859_1 nls_cp437 vfat fat snd_hda_codec_realtek snd_hda_codec_generic fuse ledtrig_audio ofpart snd_hda_codec_hdmi cmdlinepart btusb intel_spi_platform snd_hda_intel btrtl x86_pkg_temp_thermal intel_spi btbcm intel_powerclamp spi_nor btintel eeepc_wmi snd_usb_audio coretemp snd_hda_codec uvcvideo asus_wmi bluetooth snd_usbmidi_lib iTCO_wdt kvm_intel snd_hda_core videobuf2_vmalloc mei_hdcp mtd iTCO_vendor_support mxm_wmi wmi_bmof sparse_keymap snd_hwdep snd_rawmidi snd_seq_device videobuf2_memops snd_pcm videobuf2_v4l2 snd_timer videobuf2_common snd videodev kvm irqbypass input_leds ecdh_generic intel_cstate mousedev rfkill intel_uncore mei_me joydev cdc_acm media ecc e1000e intel_rapl_perf mei soundcore pcc_cpufreq i2c_i801 lpc_ich pcspkr wmi evdev mac_hid ip_tables x_tables ext4
 crc32c_generic crc16 mbcache jbd2 hid_generic usbhid hid dm_crypt dm_mod sd_mod crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel ahci libahci aesni_intel libata aes_x86_64 xhci_pci crypto_simd cryptd glue_helper xhci_hcd scsi_mod ehci_pci ehci_hcd amdgpu gpu_sched i2c_algo_bit ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm agpgart
CR2: 0000000000000360
---[ end trace 08eaa2e1d713ba4d ]---

At this point I tried killing the sway process but did not succeed even with `kill -9`. Not even `sudo reboot` completed despite killing the ssh session. I had to hard reset the machine.

Potentially related is that since roughly a week I have been experiencing intermittent screen freezes from time to time that would resolve themselves after about 10 seconds with a message like this in dmesg:

drm:drm_atomic_helper_wait_for_flip_done [drm_kms_helper]] *ERROR* [CRTC:47:crtc-0] flip_done timed out
[drm:amdgpu_dm_atomic_check [amdgpu]] *ERROR* [CRTC:47:crtc-0] hw_done or flip_done timed out