(In reply to Marek Olšák from comment #48)
> Does this fix the hangs?
> https://cgit.freedesktop.org/mesa/mesa/commit/
> ?id=d4d9ec55c589156df4edc227a86b4a8c41048d58
> 
> It changes the HTILE (HyperZ) allocation function to
> r600_aligned_buffer_create. Without that, the hardware can hang on big GPUs
> (Tahiti/Pitcairn/Hawaii/Tonga/etc), but not APUs or small GPUs. The hang
> happens when TTM decides to move HTILE to a different location with an
> unaligned physical address (which is pretty random). The hardware tries to
> access the unaligned address and boom.

Actually, I think that commit only affects Hawaii and Fiji. Other GPUs might be
unaffected, which means the Tahiti hangs are due to a different bug.