Created attachment 95961 [details]
Kernel log for session with manual radeon module loading with modesetting
enabled
Flagged as major as this prevents kernel boot if the user doesnt know how to
disable the functionality with the kernel boot parameters.
Originally reported in https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=741619
, Debian kernel v3.13 enables dpm by default - partway through the boot process
(when cryptsetup is opening encrypted disks), the kernel hangs (confirmed with
no response to ping).
The kernel boots fine with radeon.dpm=0.
Following instructions
(https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=741485#10) I booted with
radeon.modeset=0, made sure X wasn't running and radeon was unloaded, then
modprobe'd radeon modeset=1 - after a small delay everything hung.
I have attached kern.log (REISUB FTW this time it seems?), there is an X log
but that simply gave up after finding no modesetting support, before the point
where I reloaded radeon.
kern.log is verbose as I always boot with full debugging information, but in
this case its useless as nothing appears to be logged associated with the
radeon load (and I'm assuming the magic sync worked).
In terms of fighting the issue, I have C and C++ experience but no real kernel
debugging EXP and certainly nothing todo with the graphical stack.
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uname -a: Linux omega1 3.13-1-amd64 #1 SMP Debian 3.13.5-1 (2014-03-04) x86_64
GNU/Linux
Debian Testing
X server: 1.15.0
Radeon: 7.3.0