Created attachment 105313 [details]
GPU CP LOOKUP

    I am git newest mesa code, and change PAGE_SIZE alignment.
    I am closed all GPU DMA engine. R600_DMA=nodma.
    but the GPU CP is locked 
    This time the ring index is 3. it isa DMA_INDEX_RING 

  [  434.621770] radeon 0000:0a:00.0: GPU lockup CP stall for more than
5000msec
[  434.621805] radeon 0000:0a:00.0: GPU lockup (waiting for 0x0000000000000017
last fence id 0x0000000000000016)
[  434.621834] radeon 0000:0a:00.0: scheduling IB failed (-78).