I'm trying out CentOS 7 using a HP AMD laptop http://h10025.www1.hp.com/ewfrf/wc/document?cc=uk&lc=en&docname=c038...
The problem is the laptop doesn't suspend properly in runlevel 5 / graphical.target and following guides, I found that it suspends (power LED blinking) but does not resume in runlevel 3 / multi-user.target. When it locks up, the machine is unresponsive to ping/ssh so it's not just a blank screen.
Unfortunately, the only applicable guide I found on troubleshooting this is for Ubuntu, which requires the kernel to support pm_trace which isn't found in /sys/power.
Since there is a big red warning on centos.org about building/compiling my own kernel to add functions, I'm wondering if there are any alternative method to troubleshoot the issue on CentOS.
I suspect it may be related to the Radeon GPU as I notice that every now and then after fresh boot, the GUI desktop will freeze for a while and dmesg will contain errors: [drm:cik_ib_test] *ERROR* radeon: fence wait failed (-35) [drm:radeon_ib_ring_tests] *ERROR* radeon: failed testing IB on ring 2 (-35)
As a side note, this laptop had no problems with suspend/resume when it was running Ubuntu 14.04