Bug 94174

Summary: Intel Broadwell intel_cpu_fifo_underrun_irq_handler
Product: DRI Reporter: Arthur Țițeică <a.titeica>
Component: DRM/IntelAssignee: Intel GFX Bugs mailing list <intel-gfx-bugs>
Status: CLOSED FIXED QA Contact: Intel GFX Bugs mailing list <intel-gfx-bugs>
Severity: normal    
Priority: medium CC: intel-gfx-bugs
Version: XOrg git   
Hardware: x86-64 (AMD64)   
OS: Linux (All)   
Whiteboard:
i915 platform: BDW i915 features:
Attachments:
Description Flags
dmesg debug
none
xorg log
none
xrandr none

Description Arthur Țițeică 2016-02-16 13:26:46 UTC 
Kernel 4.5.0-rc4 x86_64

Laptop TOSHIBA SATELLITE Z30-B with Intel Broadwell: Intel(R) Core(TM) i5-5200U CPU @ 2.20GHz

Error in the logs: 
[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe C FIFO underrun
[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe A FIFO underrun
[drm:intel_cpu_fifo_underrun_irq_handler [i915]] *ERROR* CPU pipe B FIFO underrun

With 2 external monitors attached (HDMI and VGA) the VGA display goes blank for a second and comes back.

A strange is that the VGA monitor is detected as eDP.

I will attach dmesg with 'drm.debug=0x1e log_buf_len=1M' on the kernel command line, xrandr --verbose and Xorg.0.log.
Comment 1 Arthur Țițeică 2016-02-16 13:27:46 UTC 
Created attachment 121783 [details]
dmesg debug
Comment 2 Arthur Țițeică 2016-02-16 13:28:04 UTC 
Created attachment 121784 [details]
xorg log
Comment 3 Arthur Țițeică 2016-02-16 13:28:29 UTC 
Created attachment 121785 [details]
xrandr
Comment 4 Arthur Țițeică 2016-02-26 09:38:07 UTC 
Since 22 Feb I run kernel 4.5.0-rc5-mainline and I didn't see any more errors.

I'll go ahead and close this.

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