https://bugs.freedesktop.org/show_bug.cgi?id=79659
--- Comment #16 from Andy Furniss adf.lists@gmail.com --- (In reply to Alexander Tsoy from comment #15)
Ah.. "st/mesa,gallium: add a workaround for Unigine Heaven 4.0 and Valley 1.0" is also included in mesa-10.3. So both Heaven 4.0 and Valley 1.0 should just work. The question is why ARB_sample_shading is causing GPU lockup on VERDE. Should I open a separate bug for this issue?
Maybe check that the your /etc/drirc has the workaround and/or if you have a .drirc in your home dir that it has it also, though I haven't tested if having a .drirc under $HOME without the workaround overrides one in /etc with it.