Hang regression with R7 M370, identified possible culprit commit

Submitted by Mauro Santos

Assigned to Default DRI bug account

Link to original bug (#100222)

Description

Created attachment 130246
lspci -nnk and dmesg output

After updating from kernel 4.9 series to 4.10 series I have identified a regression when using the discrete GPU on my laptop (Lenovo Thinkpad E560).

When running any demanding application with DRI_PRIME=1 the card will hang, one example would be running 'DRI_PRIME=1 glmark2 -b texture'.

I have noticed that the content of /sys/kernel/debug/dri/1/radeon_pm_info has changed between kernel 4.9 and 4.10 when running glmark2.

With 4.9:
power level 4 sclk: 75000 mclk: 80000 vddc: 1050 vddci: 0 pcie gen: 2

With 4.10:
power level 4 sclk: 87500 mclk: 90000 vddc: 1050 vddci: 0 pcie gen: 2

This led me to revert commit 3a69adfe5617ceba04ad3cff0f9ccad470503fb2 which prevents the card from hanging.

You can find the output of lspci and dmesg in the attachment for the case with commit 3a69adfe5617ceba04ad3cff0f9ccad470503fb2 reverted.

Attachment 130246, "lspci -nnk and dmesg output":
lspci_dmesg.tar.gz