Originally Posted by Holering
Kernel-3.11-rc7 with kernel mode setting (kms) on my radeon hd 7750 causes system hang, during boot when kms initializes.
Disabled kms (nomodeset) and system boots fine. Got warning about UMS not available so I re-built kernel with UMS but that changed nothing (regarding system hang with kms).
This is normal, for newer cards the radeon driver doesn't support UMS at all, so KMS is the only option.
The hang is a bug
The only thing I can suggest at the moment is report it.