Bug 209727 - Panic in i915kms on power mode change
Summary: Panic in i915kms on power mode change
Status: Closed Overcome By Events
Alias: None
Product: Base System
Classification: Unclassified
Component: kern (show other bugs)
Version: CURRENT
Hardware: amd64 Any
: --- Affects Only Me
Assignee: freebsd-bugs (Nobody)
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2016-05-24 07:12 UTC by Juan Ramón Molina Menor
Modified: 2016-05-25 07:45 UTC (History)
1 user (show)

See Also:

Attachments
Picture of the panic (265.25 KB, image/jpeg)
2016-05-24 07:12 UTC, Juan Ramón Molina Menor 		no flags Details
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Description Juan Ramón Molina Menor 2016-05-24 07:12:21 UTC 
Created attachment 170587 [details]
Picture of the panic

While testing the freebsd-base-graphics/drm-next-4.6 branch with a Haswell (HD 4400) GPU laptop, changing the power mode (plugging or unplugging the power cord) leads to instant panic, while with the drm-next-3.9 branch, switching AC/battery modifies backlight value up and down without issues.

To reproduce:
# kldload drm2 
# sysctl dev.drm.skip_ddb=1 
# kldload i915kms 
[plug / unplug the power cord  (the result is exactly the same)] 
 
panic: IMPLEMENT ME 
…then the backtrace (attached image).