Spontaneous reboots when using RX 560

[Sylvain Munaut]

HI,

I have RX 560 2G card. It's plugged into a 16x physical / 4x
electrical slot of a X570 chipset motherboard with a Ryzen 3700X CPU.
The hardware works fine and is stable under Windows (tested with
games, benchmarks, stress-tests, ...)

But when trying for instance steam under linux, or even just the 'app
launcher' from ubuntu that has some visual effect, the machine will
instantly reboot.
Also, after the reboot, the GPU is no longer detected (lspci doesn't
show it, and under windows, its no where to be seen either). It needs
to be physically turned off and turned back on for it to work again.

I added a serial console to try to get some output and when doing that
it doesn't immediately reboot (but the rest is the same, machine is
unusable and a reboot will have the GPU not present anymore until
poweroff).

This is the output I get :

[  144.311704] amdgpu 0000:06:00.0: AMD-Vi: Event logged
[IO_PAGE_FAULT domain=0x0000 address=0xa076010100 flags=0x0010]
[  144.322734] amdgpu 0000:06:00.0: AMD-Vi: Event logged
[IO_PAGE_FAULT domain=0x0000 address=0xa076230100 flags=0x0010]
[  144.333751] amdgpu 0000:06:00.0: AMD-Vi: Event logged
[IO_PAGE_FAULT domain=0x0000 address=0xa076030100 flags=0x0010]
[  147.028625] AMD-Vi: Completion-Wait loop timed out
[  147.206336] AMD-Vi: Completion-Wait loop timed out
[  147.368260] AMD-Vi: Completion-Wait loop timed out
[  147.532296] AMD-Vi: Completion-Wait loop timed out
[  147.703269] AMD-Vi: Completion-Wait loop timed out
[  147.845840] AMD-Vi: Completion-Wait loop timed out
[  147.860950] iommu ivhd0: AMD-Vi: Event logged [IOTLB_INV_TIMEOUT
device=06:00.0 address=0x81b1c1e60]
[  148.015778] AMD-Vi: Completion-Wait loop timed out
[  148.187270] AMD-Vi: Completion-Wait loop timed out

(and then it seem to infinitely loop always printing that).

I tried Ubuntu 19.10 with 5.3.0-18-generic
Also Ubuntu 19.04 with 5.0.0-31-generic
Also tried with a DKMS module from 19.30 AMDGPU-PRO patched to build
and load under 5.3.0, all give the same result.

Cheers,

    Sylvain Munaut