[vfio-users] Issues with the i915-vga-arbiter-patch (sporadic Xorg crashes on the linux host)

[Sophie]

Hey!

my vga vfio passthrough configuration works for months like a charm, but 
newly I had some issues with crashing my Xorg on the Linux host, the KVM 
Windows machine isn't affected.

I run following setup:

> $ lspci | grep VGA
> 00:02.0 VGA compatible controller: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller (rev 06)
> 01:00.0 VGA compatible controller: NVIDIA Corporation GF114 [GeForce GTX 560] (rev a1)

using an old PCI-e GeForce 560 GTX for the Windows7 KVM, the Intel for 
the Linux host. But now my Xorg crashed constantly: > 
`pci_device_vgaarb_set_target (libpciaccess.so. #5  0x000000000049334c 
n/a (Xorg)`

Xorg crashed on all kernels with the vga-arbiter-patch. (4.8.17-1, 
4.10.1-1, 4.11.6-2 also -lts kernels)

> more of Xorg log at systemd-journal:
> Jun 24 17:42:27 Darkwing systemd-coredump[14307]: Process 1539 (Xorg) of user 0 dumped core.
> 
> Stack trace of thread 1539:
> #0 0x00007f4c6531dd09 _IO_padn (libc.so.6)
> #1 0x00007f4c652fe548 vfprintf (libc.so.6)
> #2 0x00007f4c653af9f9 __vsnprintf_chk (libc.so.6)
> #3 0x00007f4c653af925 __snprintf_chk (libc.so.6)
> #4 0x00007f4c6688ca37 pci_device_vgaarb_set_target (libpciaccess.so.
> #5 0x000000000049334c n/a (Xorg)
> #6 0x0000000000493363 n/a (Xorg)

I talked a few days ago to Mark Weiman, he offers the current vfio patch 
for Arch Linux users, but he has also no idea to solve my problem. I've 
tried his suggestion to upgrading and reinstalling all Arch Linux 
packages (also include glibc) without a success. If I disable the vfio 
patch, the Xorg runs stable!

Hope someone can help me. My only idea is to change my hardware, but I 
prefer a better solution!