I am also affected by this bug. I attached what seems to be the relevant part of syslog when the bug occurs. I don't know how to reproduce the bug, but it tends to crash my computer about every week. It tends to trigger more often when playing video or using Skype. The machine freezes and the screen goes blank after a few seconds.
My video card is reported by lshw as: product: Heathrow XT [Radeon HD 7870M] I can provide more information if needed.
Jan 5 12:09:57 sampi kernel: [1460000.023044] radeon 0000:01:00.0: ring 0 stalled for more than 10496msec Jan 5 12:09:57 sampi kernel: [1460000.023051] radeon 0000:01:00.0: GPU lockup (waiting for 0x0000000000017ad6 last fence id 0x0000000000017ad5 on ring 0) Jan 5 12:09:57 sampi kernel: [1460000.023057] radeon 0000:01:00.0: failed to get a new IB (-35) Jan 5 12:09:57 sampi kernel: [1460000.559117] radeon 0000:01:00.0: Saved 5917 dwords of commands on ring 0. Jan 5 12:09:57 sampi kernel: [1460000.559186] radeon 0000:01:00.0: GPU softreset: 0x0000006C Jan 5 12:09:57 sampi kernel: [1460000.559197] radeon 0000:01:00.0: GRBM_STATUS = 0xA0003028 Jan 5 12:09:57 sampi kernel: [1460000.559199] radeon 0000:01:00.0: GRBM_STATUS_SE0 = 0x00000006 Jan 5 12:09:57 sampi kernel: [1460000.559201] radeon 0000:01:00.0: GRBM_STATUS_SE1 = 0x00000006 Jan 5 12:09:57 sampi kernel: [1460000.559202] radeon 0000:01:00.0: SRBM_STATUS = 0x20000AC0 Jan 5 12:09:57 sampi kernel: [1460000.559259] radeon 0000:01:00.0: SRBM_STATUS2 = 0x00000000 Jan 5 12:09:57 sampi kernel: [1460000.559261] radeon 0000:01:00.0: R_008674_CP_STALLED_STAT1 = 0x00000000 Jan 5 12:09:57 sampi kernel: [1460000.559263] radeon 0000:01:00.0: R_008678_CP_STALLED_STAT2 = 0x00010000 Jan 5 12:09:57 sampi kernel: [1460000.559265] radeon 0000:01:00.0: R_00867C_CP_BUSY_STAT = 0x00000002 Jan 5 12:09:57 sampi kernel: [1460000.559267] radeon 0000:01:00.0: R_008680_CP_STAT = 0x80010243 Jan 5 12:09:57 sampi kernel: [1460000.559268] radeon 0000:01:00.0: R_00D034_DMA_STATUS_REG = 0x44483146 Jan 5 12:09:57 sampi kernel: [1460000.559270] radeon 0000:01:00.0: R_00D834_DMA_STATUS_REG = 0x44C84246 Jan 5 12:09:57 sampi kernel: [1460000.559272] radeon 0000:01:00.0: VM_CONTEXT1_PROTECTION_FAULT_ADDR 0x00000000 Jan 5 12:09:57 sampi kernel: [1460000.559274] radeon 0000:01:00.0: VM_CONTEXT1_PROTECTION_FAULT_STATUS 0x00000000 Jan 5 12:09:58 sampi kernel: [1460001.083260] radeon 0000:01:00.0: GRBM_SOFT_RESET=0x0000DDFF Jan 5 12:09:58 sampi kernel: [1460001.083314] radeon 0000:01:00.0: SRBM_SOFT_RESET=0x00100140 Jan 5 12:09:58 sampi kernel: [1460001.084463] radeon 0000:01:00.0: GRBM_STATUS = 0x00003028 Jan 5 12:09:58 sampi kernel: [1460001.084465] radeon 0000:01:00.0: GRBM_STATUS_SE0 = 0x00000006 Jan 5 12:09:58 sampi kernel: [1460001.084467] radeon 0000:01:00.0: GRBM_STATUS_SE1 = 0x00000006 Jan 5 12:09:58 sampi kernel: [1460001.084469] radeon 0000:01:00.0: SRBM_STATUS = 0x200000C0 Jan 5 12:09:58 sampi kernel: [1460001.084525] radeon 0000:01:00.0: SRBM_STATUS2 = 0x00000000 Jan 5 12:09:58 sampi kernel: [1460001.084528] radeon 0000:01:00.0: R_008674_CP_STALLED_STAT1 = 0x00000000 Jan 5 12:09:58 sampi kernel: [1460001.084530] radeon 0000:01:00.0: R_008678_CP_STALLED_STAT2 = 0x00000000 Jan 5 12:09:58 sampi kernel: [1460001.084532] radeon 0000:01:00.0: R_00867C_CP_BUSY_STAT = 0x00000000 Jan 5 12:09:58 sampi kernel: [1460001.084533] radeon 0000:01:00.0: R_008680_CP_STAT = 0x00000000 Jan 5 12:09:58 sampi kernel: [1460001.084535] radeon 0000:01:00.0: R_00D034_DMA_STATUS_REG = 0x44C83D57 Jan 5 12:09:58 sampi kernel: [1460001.084537] radeon 0000:01:00.0: R_00D834_DMA_STATUS_REG = 0x44C83D57 Jan 5 12:09:58 sampi kernel: [1460001.084672] radeon 0000:01:00.0: GPU reset succeeded, trying to resume Jan 5 12:09:58 sampi NetworkManager[784]: <info> (wlan0): supplicant interface state: starting -> down Jan 5 12:09:58 sampi kernel: [1460001.113559] [drm] probing gen 2 caps for device 8086:151 = 261ad03/e Jan 5 12:09:58 sampi kernel: [1460001.113564] [drm] PCIE gen 3 link speeds already enabled Jan 5 12:09:58 sampi kernel: [1460001.116459] [drm] PCIE GART of 1024M enabled (table at 0x0000000000276000). Jan 5 12:09:58 sampi kernel: [1460001.116795] radeon 0000:01:00.0: WB enabled Jan 5 12:09:58 sampi kernel: [1460001.116799] radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000080000c00 and cpu addr 0xffff8800cde5ec00 Jan 5 12:09:58 sampi kernel: [1460001.116802] radeon 0000:01:00.0: fence driver on ring 1 use gpu addr 0x0000000080000c04 and cpu addr 0xffff8800cde5ec04 Jan 5 12:09:58 sampi kernel: [1460001.116805] radeon 0000:01:00.0: fence driver on ring 2 use gpu addr 0x0000000080000c08 and cpu addr 0xffff8800cde5ec08 Jan 5 12:09:58 sampi kernel: [1460001.116807] radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000080000c0c and cpu addr 0xffff8800cde5ec0c Jan 5 12:09:58 sampi kernel: [1460001.116810] radeon 0000:01:00.0: fence driver on ring 4 use gpu addr 0x0000000080000c10 and cpu addr 0xffff8800cde5ec10 Jan 5 12:09:58 sampi kernel: [1460001.117210] radeon 0000:01:00.0: fence driver on ring 5 use gpu addr 0x0000000000075a18 and cpu addr 0xffffc90005135a18 Jan 5 12:09:58 sampi kernel: [1460001.294780] [drm] ring test on 0 succeeded in 1 usecs Jan 5 12:09:58 sampi kernel: [1460001.294785] [drm] ring test on 1 succeeded in 1 usecs Jan 5 12:09:58 sampi kernel: [1460001.294788] [drm] ring test on 2 succeeded in 1 usecs Jan 5 12:09:58 sampi kernel: [1460001.294802] [drm] ring test on 3 succeeded in 10 usecs Jan 5 12:09:58 sampi kernel: [1460001.294807] [drm] ring test on 4 succeeded in 3 usecs Jan 5 12:09:58 sampi kernel: [1460001.471105] [drm] ring test on 5 succeeded in 2 usecs Jan 5 12:09:58 sampi kernel: [1460001.471110] [drm] UVD initialized successfully.