dix/dispatch.c:4049: AttachOffloadGPU: Assertion `new->current_master == pScreen' failed.

[Paul Menzel]

Dear Michel,


Thank you for your reply.


On 08/14/17 03:15, Michel Dänzer wrote:
> On 11/08/17 01:02 AM, Paul Menzel wrote:

>> On 08/10/17 15:14, Paul Menzel wrote:
>>
>>> Getting Dell Precision 3620 systems with an Intel Skylake system
>>> i7-6700K, and an external AMD graphics card, the X.Org server does not
>>> start and hits an assert. The software stack is Linux 4.9.38 and
>>> 4.12.5, X.Org server 1.19.3 and xf86-video-amdgpu 1.3.0.
>>>
>>> ```
>>> $ lspci -nn -s 00:01.0
>>> 00:01.0 PCI bridge [0604]: Intel Corporation Skylake PCIe Controller
>>> (x16) [8086:1901] (rev 07)
>>> $ lspci -nn -s 1:00.0
>>> 01:00.0 VGA compatible controller [0300]: Advanced Micro Devices, Inc.
>>> [AMD/ATI] Bonaire [FirePro W5100] [1002:6649]
>>> ```
>>>
>>> The monitor’s DVI cable and a DVI-to-DP adapter is plugged into the
>>> DisplayPort port of the AMD graphics card. The TTY login screen can be
>>> shortly seen before GDM tries to start.
>>>
>>> Please find the last X.Org server messages below.
>>>
>>> ```
>>> […]
>>> (II) Loading /usr/lib/xorg/modules/libfb.so
>>> (II) Module fb: vendor="X.Org Foundation"
>>>           compiled for 1.19.3, module version = 1.0.0
>>> (--) Depth 24 pixmap format is 32 bpp
>>> (==) modeset(G0): Backing store enabled
>>> (==) modeset(G0): Silken mouse enabled
>>> (II) modeset(G0): RandR 1.2 enabled, ignore the following RandR
>>> disabled message.
>>> (==) modeset(G0): DPMS enabled
>>> (II) modeset(G0): [DRI2] Setup complete
>>> (II) modeset(G0): [DRI2]   DRI driver: i965
>>> (II) modeset(G0): [DRI2]   VDPAU driver: i965
>>> (II) AMDGPU(0): [DRI2] Setup complete
>>> (II) AMDGPU(0): [DRI2]   DRI driver: radeonsi
>>> (II) AMDGPU(0): [DRI2]   VDPAU driver: radeonsi
>>> (II) AMDGPU(0): Front buffer pitch: 6912 bytes
>>> (II) AMDGPU(0): SYNC extension fences enabled
>>> (II) AMDGPU(0): Present extension enabled
>>> (==) AMDGPU(0): DRI3 enabled
>>> (==) AMDGPU(0): Backing store enabled
>>> (II) AMDGPU(0): Direct rendering enabled
>>> (II) AMDGPU(0): Use GLAMOR acceleration.
>>> (II) AMDGPU(0): Acceleration enabled
>>> (==) AMDGPU(0): DPMS enabled
>>> (==) AMDGPU(0): Silken mouse enabled
>>> (II) AMDGPU(0): Set up textured video (glamor)
>>> (II) AMDGPU(0): RandR 1.2 enabled, ignore the following RandR disabled
>>> message.
>>> (--) RandR disabled
>>> Xorg:
>>> /dev/shm/bee-root/xorg-server/xorg-server-1.19.3-0/source/dix/dispatch.c:4049:
>>> AttachOffloadGPU: Assertion `new->current_master == pScreen' failed.
>>> ```
>>>
>>> The USB keyboard does not work, and the system has to be controlled
>>> remotely over SSH. Plugging in the DisplayPort cable into the internal
>>> Intel graphics ports the Linux messages can be seen, but nothing else
>>> works. Stopping GDM does not bring back the TTY screen. The keyboard
>>> still does work. Plugging the USB cable out and back in doesn’t fix it
>>> either.
>>>
>>> Trying to disable the internal Intel graphics card, did not fix the
>>> problem either.
>>
>> Blacklisting the module *i915* works around the problem.
>>
>> Please tell me if you want me to create a bug report for this issue,
>> and, if yes, what part in the graphics stack this problem belongs to.
> 
> It's hard to be sure without seeing a backtrace of the assertion
> failure, but I'd say start at
> https://bugs.freedesktop.org/enter_bug.cgi?product=xorg&component=Server/Ext/RandR.

Do you know why the stack trace is not present in the X server log? I 
was able to get a stack trace as root and with GDB. Issue #102222 
(dix/dispatch.c:4049: AttachOffloadGPU: Assertion `new->current_master 
== pScreen' failed.) tracks this problem now, and the stack traces are 
attached there.


Kind regards,

Paul


[1] https://bugs.freedesktop.org/show_bug.cgi?id=102222