Bug 650554 – sys-kernel/gentoo-sources-4.15.9: crash in i915 driver when docked

• Product: Gentoo Linux
• Status: RESOLVED OBSOLETE

[Description d.rauber 2018-03-15 11:13:42 UTC]

My Dell Latitude E7450 crashes with gentoo 4.15.9 kernel directly after boot. This happens only when the laptop is in the docking station. When undocked, the machine is booting fine, but also crashes as soon as I put it in the docking station. Kernel 4.9.76-r1 is working without problems.

log messages:
Mär 14 12:12:55 etkbox kernel: [drm:intel_cpu_fifo_underrun_irq_handler] *ERROR* CPU pipe A FIFO underrun
Mär 14 12:12:55 etkbox kernel: [drm:pipe_config_err] *ERROR* mismatch in pixel_rate (expected 148500, found 247499)
Mär 14 12:12:55 etkbox kernel: [drm:pipe_config_err] *ERROR* mismatch in shared_dpll (expected 00000000cac9ad22, found 00000000f93ec4c3)
Mär 14 12:12:55 etkbox kernel: [drm:pipe_config_err] *ERROR* mismatch in base.adjusted_mode.crtc_clock (expected 148500, found 247499)
Mär 14 12:12:55 etkbox kernel: [drm:pipe_config_err] *ERROR* mismatch in port_clock (expected 162000, found 270000)
Mär 14 12:12:55 etkbox kernel: ------------[ cut here ]------------
Mär 14 12:12:55 etkbox kernel: pipe state doesn't match!
Mär 14 12:12:55 etkbox kernel: WARNING: CPU: 1 PID: 2723 at drivers/gpu/drm/i915/intel_display.c:11601 intel_atomic_commit_tail+0xb85/0xc90

Full log attached.

This is probably the same bug that is described here:
https://bugzilla.redhat.com/show_bug.cgi?id=1549042



Reproducible: Always

Steps to Reproduce:
1. booting up when docked or put the running machine in the docking station


Actual Results:  
System crashes and has to be rebooted.

[Comment 1 d.rauber 2018-03-15 11:18:17 UTC]

Created attachment 523996 [details]
syslog

[Comment 2 d.rauber 2018-03-15 11:19:22 UTC]

Created attachment 523998 [details]
lspci

[Comment 3 Romain Perier 2018-03-27 11:38:02 UTC]

Hi,

Have you the same problem with 4.15.13 ?

Thanks

[Comment 4 d.rauber 2018-03-29 10:26:24 UTC]

Created attachment 526038 [details]
log with drm.debug=0xe

Problem still there in kernel 4.15.13. New log attached with drm.debug=0xe set.

[Comment 5 d.rauber 2018-03-29 11:01:47 UTC]

Created attachment 526042 [details, diff]
drm-i915-dp-Write-to-SET_POWER-dpcd-to-enable-MST-hub-gentoo.patch

I tried the patch from https://patchwork.freedesktop.org/patch/210500/ and it fixes my problem. Had to manually fix the patch for my kernel. New patch attached.

[Comment 6 Viktor Levin 2018-03-29 15:15:01 UTC]

Maybe similar bug: https://bugs.gentoo.org/649298
Kernel hangs on boot.

[Comment 7 Mike Pagano 2018-03-29 23:49:10 UTC]

Created attachment 526140 [details, diff]
backported i915 patch from Linus' tree

I had to tweak the patch to apply to 4.15? Did you do the same?
Can you test this one against 4.15.

You can apply with:

patch -p1 < /location/of/2700_i915-to-SET-POWER-dpcd-to-enable-MST-hub.patch

[Comment 8 d.rauber 2018-04-02 13:30:57 UTC]

Your patch is the same as mine, only difference is the deleted comment. I also had to tweak it in order to work.

[Comment 9 Mike Pagano 2018-06-13 13:20:24 UTC]

4.15 is EOL'ed and the upstream patch is in kernels >= 4.16.