Intel Skylake iGPU (i915) breaks Proxmox 4.1

[morph027]

I've just deployed PVE 4.1 on a machine going to be a storage server (samba inside lxc). As theres not that much load, we decided to cut some money and just use an i3-6100. Installer went through without problems, but first boot hangs just 8ms after initrd's kernel kicks in. It took me a while to find out (because i've deployed almost exactly the same system last week successfully - besides the cpu being a Skylake Xeon v5) randomly disabling various kernel modules at grub cmdline. Once, last thing i saw before freezing was the drm module being loaded and i whonder why the heck i need such a thing on a server. Next boot, next try, added

modprobe.disabled=i915 modprobe.disabled=drm modprobe.disabled=drm_kms_helper

to grub kernel cmdline and it worked straight.

Add to /etc/modprobe.d/i915.conf:

blacklist drm_kms_helper
blacklist drm
blacklist i915

and run

update-initramfs -k all -u

and everything works as of next boot.

As for whoever there are also Xeons with integrated GPU, we should investigate this further.

Didn't try with older boards/cpu/pve (might try at home on my laptop). If this is a general issue, this should be added to the default installation.

 

[morph027]

Ok, just grabbed one of my lab servers ssd and booted my latest skylake notebook from it. Suprise, suprise, does work. lsmod clearly indicates the 3 modules being loaded. So it isn't a generally problem at all.

Configuration where bug occurs:

- Intel Silver Pass Xeon Board S1200SPL
- Intel Core i3-6100
- ZFS RAID1 installation on 2 Samsung SM843T (directly connected via AHCI @ onboard SATA)

If in any weird case i'll get my hands on a Xeon with integrated GPU (hopefully not ), i'll test things out too.

However, just for the books, the solution in first post helped with this special issue.

 

[bramb]

Proxmox doesn't like the Kaby Lake Xeon's with integrated graphics. A lot of random freezes with blank screens with no errors. After disabling integrated graphics in the BIOS everything worked fine. Only two whole nights of debugging (eventually I got a error to work with).

I tried proxmox 4.1, 4.3 and 4.4. All the same problem.

Configuration:
- Intel Xeon E3-1245 v6
- Supermicro X11SSH-F
- 4x Kingston Certified 16GB DDR4 2133Mhz ECC