After upgrading to kernel 4.9 my machine hangs during shutdown/reboot.
the shutdown/reboot procedure starts and finish with systemd unmount all partitions.
Monitor poweroff but the gpu led (motherboard) is ON.
add "radeon.dpm=0" in kernel line solved problem.
vga: HD5770 Vapor-X (Evergreen)
reassign to the graphics experts.
Created attachment 253121 [details]
Does the attached patch help?
ok fixed, thanks!
I can confirm that the patch works. Applied to kernel 4.9.6.
graphics card: Cypress XT [Radeon HD 5870]
Glad the patch made it into the latest kernel 4.9 (4.9.7). Same HD5770 as upcwteng.
Same problem after upgrading to kernel 4.12.10-1-ARCH (ArchLinux 64Bit)
Radeon 5770 Evergreen