(In reply to taijian from comment #15)
> Created attachment 140733 [details]
> dmesg output 4.18rc5 + drm-fixes-2018-07-20
>=20
> OK, so I have some new, probably interesting dmesg output with the lat=
est
> mainline build.
>=20
> What's happening here is that the system boots up, then my background
> display brightness service goes to work (see here:
> https://github.com/FedeDP=
/Clight and here:
> https://github.com/FedeD=
P/Clightd) and tries to adjust screen brightness.
> This leads to a number of=20
>=20
>   RIP: 0010:dm_dp_aux_transfer+0xa5/0xb0 [amdgpu]
>=20
> trace calls and then the system freeezes completely. And I mean comple=
tely,
> as in not even sysrq + REISUB does anything. Does this help in any way=
?

So i tried with kernel 4.18 rc.1 from here -
https://cgit.freedesktop.org/~agd5f/linux/log/?h=3Damd-staging-drm=
-next

and 2 cards=20

Provider 0: id: 0x81 cap: 0x9, Source Output, Sink Offload crtcs: 5 outputs=
: 3
associated providers: 1 name:AMD Radeon (TM) RX 460 Graphics @ pci:0000=
:0b:00.0
Provider 1: id: 0x49 cap: 0x6, Sink Output, Source Offload crtcs: 6 outputs=
: 4
associated providers: 1 name:AMD Radeon (TM) RX 480 Graphics @ pci:0000=
:08:00.0

Where RX 460 is the default and RX 480 is the secondary. I ran both glxgears
and glxinfo multiple time with DRI_PRIME=3D1 and haven't observed any issue=
s.

>>From the log I see GPU pci config reset print - where does it come from ? D=
id
you trigger PCI reset for the device  manually or did it happen once you tr=
ied
to run any application with DRI_PRIME=3D1 ? Which device is 0000:01:00.0 -
primary or secondary ?