Steve Vai froze my machine ... but most probably an amdgpu issue

[rgc]

shimer/flicker happened again once on 338.
zzz and wake-up again seems to restore things back to normal.
updated to the following in the last few days
and haven't encountered shimer/flicker or the original issue (X crash)
kern.version=OpenBSD 6.9-beta (GENERIC.MP) #344: Fri Feb 19 10:01:51 MST 2021
kern.version=OpenBSD 6.9-beta (GENERIC.MP) #350: Sun Feb 21 11:04:59 MST 2021

just sharing some information for those tracking down amdgpu issues

no issues until today
machine has been suspened several times thru the course of the week
(last update was 03/31 with #436, shown below)

watching Steve Vai on youtube (firefox-esr) and screen froze
i could ssh to the machine. top showed machine was mostly idle.

OpenBSD 6.9-beta (GENERIC.MP) #436: Mon Mar 29 12:55:53 MDT 2021
***@amd64.openbsd.org:/usr/src/sys/arch/amd64/compile/GENERIC.MP
real mem = 25417670656 (24240MB)
avail mem = 24631955456 (23490MB)
random: good seed from bootblocks
mpath0 at root
scsibus0 at mpath0: 256 targets
mainbus0 at root
bios0 at mainbus0: SMBIOS rev. 3.2 @ 0xbd60a000 (24 entries)
bios0: vendor American Megatrends Inc. version "GU502DU.305" date 01/07/2021
bios0: ASUSTeK COMPUTER INC. Zephyrus G GU502DU_GA502DU
acpi0 at bios0: ACPI 6.0
acpi0: sleep states S0 S3 S4 S5
acpi0: tables DSDT FACP APIC FPDT FIDT ECDT SSDT MCFG MSDM SSDT HPET UEFI VFCT TPM2 IVRS SSDT CRAT CDIT BGRT SSDT SSDT SSDT SSDT SSDT SSDT WSMT
acpi0: wakeup devices GPP0(S4) GPP1(S4) GPP4(S4) GPP5(S4) GPP6(S4) GP17(S4) XHC0(S4) XHC1(S4) GP18(S4)
acpitimer0 at acpi0: 3579545 Hz, 32 bits
acpimadt0 at acpi0 addr 0xfee00000: PC-AT compat

8< snipped >8<

last log below, before i finally rebooted the system

[drm] *ERROR* Error in DP aux read transaction, not writing source specific data
[drm] *ERROR* ring sdma0 timeout, signaled seq=26973, emitted seq=26973
[drm] *ERROR* Process information: process pid 0 thread pid 0

fetching new snapshots now.
and will continue to watch Steve Vai (it's a Friday night in Japan)

rgc ~