desktop-packages team mailing list archive

[Launchpad Bug Tracker <1290775@xxxxxxxxxxxxxxxxxx>]

[Expired for xorg (Ubuntu) because there has been no activity for 60
days.]

** Changed in: xorg (Ubuntu)
       Status: Incomplete => Expired

-- 
You received this bug notification because you are a member of Desktop
Packages, which is subscribed to xorg in Ubuntu.
https://bugs.launchpad.net/bugs/1290775

Title:
  X freeze, garbled output, "*ERROR* Failed to schedule IB" on RV635/M86
  (Radeon HD3650) and RV620

Status in xorg package in Ubuntu:
  Expired

Bug description:
  On two different computers stragnge display errors are encountered.

  Machine A is a laptop:
  uname: Linux x 3.11.0-18-generic #32-Ubuntu SMP Tue Feb 18 21:11:14 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
  /proc/cmdline: BOOT_IMAGE=/boot/vmlinuz-3.11.0-18-generic root=UUID=... ro quiet splash vt.handoff=7

  Machine B is desktop PC:
  uname: Linux x 3.11.0-18-generic #32-Ubuntu SMP Tue Feb 18 21:11:14 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux
  /proc/cmdline: root=/dev/mapper/somelv ro quiet splash

  Both machines are running Ubuntu 13.10, with frequent updates (say, at least or more than once a week).
  Both are running xserver-xorg-video-ati 1:7.2.0-0ubuntu10, neither has installed anything with fglrx nor catalyst in package name.

  On B (desktop PC), display was occasionaly garbled with small artefacts (like few pixel lines of random dots), and occasionally screen freezes, than goes blank for a second, then works normaly again for some time - but after 3-4 such cycles, display permanently freezes. Restarting lightdm through one of VT consoles helped. Some applications, like firefox, caused these problems to be more frequent.  
  Then, as machine was frequently updated in hope of a fix, this changed, but to worse. Screen went completely garbled, mouse pointer turned to large square full of random noise, but underlying applications were probably running. VT consoles also went garbled and hard to use. Both DVI outputs were affected.

  On A machine display is mostly blank (though BIOS and GRUP screens are presented OK), sometimes graphical greeter (logon screen) is displayed, sometimes not. Bu in either case machine freezes and no logon is possible.
  Sometimes SysRq keys are working to reboot can be done, sometimes not.
  As this machine is equiped with swithchable graphics, when other GPU (Intel, integrated) is used display is presented ok.

  Machine A lshw extract:
      description: Notebook
      product: 20553AG ()
      vendor: LENOVO
      version: ThinkPad T500
  ...
             *-display
                  description: VGA compatible controller
                  product: RV635/M86 [Mobility Radeon HD 3650]
                  vendor: Advanced Micro Devices, Inc. [AMD/ATI]
                  physical id: 0
                  bus info: pci@0000:01:00.0
                  version: 00
                  width: 32 bits
                  clock: 33MHz
                  capabilities: pm pciexpress msi vga_controller bus_master cap_list rom
                  configuration: driver=radeon latency=0
                  resources: irq:48 memory:d0000000-dfffffff ioport:2000(size=256) memory:cfff0000-cfffffff memory:cff00000-cff1ffff

  Machine A dmesg extract:
  ...
  [    0.881667] [drm] radeon kernel modesetting enabled.
  [    0.881891] [drm] initializing kernel modesetting (RV635 0x1002:0x9591 0x17AA:0x2117).
  [    0.881913] [drm] register mmio base: 0xCFFF0000
  [    0.881914] [drm] register mmio size: 65536
  [    0.882003] ATOM BIOS: M86M
  [    0.882021] radeon 0000:01:00.0: VRAM: 256M 0x0000000000000000 - 0x000000000FFFFFFF (256M used)
  [    0.882023] radeon 0000:01:00.0: GTT: 512M 0x0000000010000000 - 0x000000002FFFFFFF
  [    0.882025] [drm] Detected VRAM RAM=256M, BAR=256M
  [    0.882026] [drm] RAM width 128bits DDR
  [    0.882059] [TTM] Zone  kernel: Available graphics memory: 1988596 kiB
  [    0.882061] [TTM] Initializing pool allocator
  [    0.882064] [TTM] Initializing DMA pool allocator
  [    0.882081] [drm] radeon: 256M of VRAM memory ready
  [    0.882082] [drm] radeon: 512M of GTT memory ready.
  [    0.882093] [drm] GART: num cpu pages 131072, num gpu pages 131072
  [    0.887931] [drm] Loading RV635 Microcode
  [    0.888799] [drm] PCIE GART of 512M enabled (table at 0x0000000000040000).
  [    0.888848] radeon 0000:01:00.0: WB enabled
  [    0.888850] radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000010000c00 and cpu addr 0xffff880150118c00
  [    0.888852] radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000010000c0c and cpu addr 0xffff880150118c0c
  [    0.888854] [drm] Supports vblank timestamp caching Rev 1 (10.10.2010).
  [    0.888856] [drm] Driver supports precise vblank timestamp query.
  [    0.888879] radeon 0000:01:00.0: irq 48 for MSI/MSI-X
  [    0.888889] radeon 0000:01:00.0: radeon: using MSI.
  [    0.888912] [drm] radeon: irq initialized.
  [    0.920625] [drm] ring test on 0 succeeded in 1 usecs
  [    0.920683] [drm] ring test on 3 succeeded in 1 usecs
  [    0.921179] [drm] ib test on ring 0 succeeded in 0 usecs
  [    0.921193] [drm] ib test on ring 3 succeeded in 0 usecs
  [    0.921699] [drm] radeon atom DIG backlight initialized
  [    0.921701] [drm] Radeon Display Connectors
  [    0.921702] [drm] Connector 0:
  [    0.921703] [drm]   DVI-I-1
  [    0.921704] [drm]   HPD3
  [    0.921705] [drm]   DDC: 0x7e60 0x7e60 0x7e64 0x7e64 0x7e68 0x7e68 0x7e6c 0x7e6c
  [    0.921706] [drm]   Encoders:
  [    0.921707] [drm]     DFP1: INTERNAL_UNIPHY
  [    0.921709] [drm] Connector 1:
  [    0.921710] [drm]   LVDS-1
  [    0.921711] [drm]   DDC: 0x7e40 0x7e40 0x7e44 0x7e44 0x7e48 0x7e48 0x7e4c 0x7e4c
  [    0.921712] [drm]   Encoders:
  [    0.921713] [drm]     LCD1: INTERNAL_KLDSCP_LVTMA
  [    0.921714] [drm] Connector 2:
  [    0.921715] [drm]   DP-1
  [    0.921715] [drm]   HPD1
  [    0.921717] [drm]   DDC: 0x7e20 0x7e20 0x7e24 0x7e24 0x7e28 0x7e28 0x7e2c 0x7e2c
  [    0.921717] [drm]   Encoders:
  [    0.921718] [drm]     DFP2: INTERNAL_UNIPHY
  [    0.921719] [drm] Connector 3:
  [    0.921720] [drm]   VGA-1
  [    0.921722] [drm]   DDC: 0x7e50 0x7e50 0x7e54 0x7e54 0x7e58 0x7e58 0x7e5c 0x7e5c
  [    0.921722] [drm]   Encoders:
  [    0.921723] [drm]     CRT1: INTERNAL_KLDSCP_DAC1
  [    0.921825] [drm] radeon: power management initialized
  ...
  [    1.850194] [drm] fb mappable at 0xD0142000
  [    1.850196] [drm] vram apper at 0xD0000000
  [    1.850197] [drm] size 7299072
  [    1.850198] [drm] fb depth is 24
  [    1.850199] [drm]    pitch is 6912
  [    1.850275] fbcon: radeondrmfb (fb0) is primary device
  ...
  [    2.128153] Console: switching to colour frame buffer device 210x65
  [    2.132066] radeon 0000:01:00.0: fb0: radeondrmfb frame buffer device
  [    2.132068] radeon 0000:01:00.0: registered panic notifier
  [    2.132078] [drm] Initialized radeon 2.34.0 20080528 for 0000:01:00.0 on minor 0
  ...
  [   73.156105] radeon 0000:01:00.0: GPU lockup CP stall for more than 10000msec
  [   73.156110] radeon 0000:01:00.0: GPU lockup (waiting for 0x000000000000002c last fence id 0x000000000000000e)
  ...
  [   73.672317] radeon 0000:01:00.0: couldn't schedule ib
  [   73.672321] [drm:radeon_cs_ib_chunk] *ERROR* Failed to schedule IB !
  [   73.674025] radeon 0000:01:00.0: couldn't schedule ib
  [   73.674027] [drm:radeon_cs_ib_chunk] *ERROR* Failed to schedule IB !
  [   73.705580] radeon 0000:01:00.0: couldn't schedule ib
  [   73.705585] [drm:radeon_cs_ib_chunk] *ERROR* Failed to schedule IB !
  [   73.716366] radeon 0000:01:00.0: couldn't schedule ib
  [   73.716369] [drm:radeon_cs_ib_chunk] *ERROR* Failed to schedule IB !
  [   73.729614] radeon 0000:01:00.0: couldn't schedule ib
  [   73.729619] [drm:radeon_cs_ib_chunk] *ERROR* Failed to schedule IB !
  (repeating many times)


  Machine B dmesg extract:
  [    0.596523] [drm] Radeon Display Connectors
  [    0.596525] [drm] Connector 0:
  [    0.596526] [drm]   DIN-1
  [    0.596527] [drm]   Encoders:
  [    0.596528] [drm]     TV1: INTERNAL_KLDSCP_DAC2
  [    0.596530] [drm] Connector 1:
  [    0.596531] [drm]   DVI-I-1
  [    0.596532] [drm]   HPD2
  [    0.596534] [drm]   DDC: 0x7e40 0x7e40 0x7e44 0x7e44 0x7e48 0x7e48 0x7e4c 0x7e4c
  [    0.596535] [drm]   Encoders:
  [    0.596536] [drm]     CRT1: INTERNAL_KLDSCP_DAC1
  [    0.596537] [drm]     DFP1: INTERNAL_UNIPHY
  [    0.596539] [drm] Connector 2:
  [    0.596540] [drm]   DVI-I-2
  [    0.596541] [drm]   HPD1
  [    0.596543] [drm]   DDC: 0x7e50 0x7e50 0x7e54 0x7e54 0x7e58 0x7e58 0x7e5c 0x7e5c
  [    0.596544] [drm]   Encoders:
  [    0.596545] [drm]     CRT2: INTERNAL_KLDSCP_DAC2
  [    0.596546] [drm]     DFP2: INTERNAL_KLDSCP_LVTMA
  [    0.596574] [drm] Internal thermal controller with fan control
  [    0.596605] [drm] radeon: power management initialized
  [    0.695710] [drm] fb mappable at 0xD0142000
  [    0.695712] [drm] vram apper at 0xD0000000
  [    0.695713] [drm] size 8294400
  [    0.695714] [drm] fb depth is 24
  [    0.695716] [drm]    pitch is 7680
  [    0.695779] fbcon: radeondrmfb (fb0) is primary device
  ...
  [    0.924331] Console: switching to colour frame buffer device 210x65
  [    0.928594] radeon 0000:01:00.0: fb0: radeondrmfb frame buffer device
  [    0.928596] radeon 0000:01:00.0: registered panic notifier
  ...
  [  343.872027] radeon 0000:01:00.0: GPU lockup CP stall for more than 10000msec
  [  343.872034] radeon 0000:01:00.0: GPU lockup (waiting for 0x0000000000000160)
  [  343.872039] radeon 0000:01:00.0: failed to get a new IB (-35)
  [  343.872042] [drm:radeon_cs_ib_chunk] *ERROR* Failed to get ib !
  [  343.873097] radeon 0000:01:00.0: Saved 2777 dwords of commands on ring 0.
  [  343.873106] radeon 0000:01:00.0: GPU softreset: 0x00000019
  [  343.873109] radeon 0000:01:00.0:   R_008010_GRBM_STATUS      = 0xA27334E0
  [  343.873112] radeon 0000:01:00.0:   R_008014_GRBM_STATUS2     = 0x00000103
  [  343.873114] radeon 0000:01:00.0:   R_000E50_SRBM_STATUS      = 0x200000C0
  [  343.873117] radeon 0000:01:00.0:   R_008674_CP_STALLED_STAT1 = 0x01000000
  [  343.873120] radeon 0000:01:00.0:   R_008678_CP_STALLED_STAT2 = 0x00001002
  [  343.873122] radeon 0000:01:00.0:   R_00867C_CP_BUSY_STAT     = 0x00028486
  [  343.873125] radeon 0000:01:00.0:   R_008680_CP_STAT          = 0x80838645
  [  343.873128] radeon 0000:01:00.0:   R_00D034_DMA_STATUS_REG   = 0x44C83D57
  [  343.943542] radeon 0000:01:00.0: R_008020_GRBM_SOFT_RESET=0x00007FEF
  [  343.943596] radeon 0000:01:00.0: SRBM_SOFT_RESET=0x00000100
  [  343.945684] radeon 0000:01:00.0:   R_008010_GRBM_STATUS      = 0xA0003030
  [  343.945687] radeon 0000:01:00.0:   R_008014_GRBM_STATUS2     = 0x00000003
  [  343.945689] radeon 0000:01:00.0:   R_000E50_SRBM_STATUS      = 0x200080C0
  [  343.945691] radeon 0000:01:00.0:   R_008674_CP_STALLED_STAT1 = 0x00000000
  [  343.945694] radeon 0000:01:00.0:   R_008678_CP_STALLED_STAT2 = 0x00000000
  [  343.945696] radeon 0000:01:00.0:   R_00867C_CP_BUSY_STAT     = 0x00000000
  [  343.945698] radeon 0000:01:00.0:   R_008680_CP_STAT          = 0x80100000
  [  343.945701] radeon 0000:01:00.0:   R_00D034_DMA_STATUS_REG   = 0x44C83D57
  [  343.945705] radeon 0000:01:00.0: GPU reset succeeded, trying to resume
  [  343.961937] [drm] PCIE gen 2 link speeds already enabled
  [  343.963722] [drm] PCIE GART of 512M enabled (table at 0x0000000000040000).
  [  343.963754] radeon 0000:01:00.0: WB enabled
  [  343.963757] radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000020000c00 and cpu addr 0xffff8801a3a0fc00
  [  343.963760] radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000020000c0c and cpu addr 0xffff8801a3a0fc0c
  [  343.994802] [drm] ring test on 0 succeeded in 1 usecs
  [  343.994860] [drm] ring test on 3 succeeded in 1 usecs
  [  344.155920] [drm] ib test on ring 0 succeeded in 0 usecs
  [  344.155947] [drm] ib test on ring 3 succeeded in 1 usecs
  ...
  Another machine B dmesg extract:
  [    0.528297] [drm] radeon kernel modesetting enabled.
  [    0.529749] [drm] initializing kernel modesetting (RV620 0x1002:0x95C5 0x174B:0xE670).
  [    0.529771] [drm] register mmio base: 0xFE8E0000
  [    0.529772] [drm] register mmio size: 65536
  [    0.529869] ATOM BIOS: 11X
  [    0.529888] radeon 0000:01:00.0: VRAM: 512M 0x0000000000000000 - 0x000000001FFFFFFF (512M used)
  [    0.529891] radeon 0000:01:00.0: GTT: 512M 0x0000000020000000 - 0x000000003FFFFFFF
  [    0.529893] [drm] Detected VRAM RAM=512M, BAR=256M
  [    0.529894] [drm] RAM width 64bits DDR
  [    0.530535] [TTM] Zone  kernel: Available graphics memory: 3056138 kiB
  [    0.530537] [TTM] Zone   dma32: Available graphics memory: 2097152 kiB
  [    0.530539] [TTM] Initializing pool allocator
  [    0.530543] [TTM] Initializing DMA pool allocator
  [    0.530565] [drm] radeon: 512M of VRAM memory ready
  [    0.530566] [drm] radeon: 512M of GTT memory ready.
  [    0.530589] [drm] GART: num cpu pages 131072, num gpu pages 131072
  [    0.531473] [drm] enabling PCIE gen 2 link speeds, disable with radeon.pcie_gen2=0
  ...
  [    0.563518] [drm] Loading RV620 Microcode
  [    0.564295] [drm] PCIE GART of 512M enabled (table at 0x0000000000040000).
  [    0.564350] radeon 0000:01:00.0: WB enabled
  [    0.564354] radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000020000c00 and cpu addr 0xffff8801a3a0fc00
  [    0.564356] radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000020000c0c and cpu addr 0xffff8801a3a0fc0c
  [    0.564358] [drm] Supports vblank timestamp caching Rev 1 (10.10.2010).
  [    0.564359] [drm] Driver supports precise vblank timestamp query.
  [    0.564381] radeon 0000:01:00.0: irq 45 for MSI/MSI-X
  [    0.564393] radeon 0000:01:00.0: radeon: using MSI.
  [    0.564415] [drm] radeon: irq initialized.
  [    0.595827] [drm] ring test on 0 succeeded in 0 usecs
  [    0.595883] [drm] ring test on 3 succeeded in 1 usecs
  [    0.596235] [drm] ib test on ring 0 succeeded in 0 usecs
  [    0.596247] [drm] ib test on ring 3 succeeded in 0 usecs
  [    0.596523] [drm] Radeon Display Connectors
  [    0.596525] [drm] Connector 0:
  [    0.596526] [drm]   DIN-1
  [    0.596527] [drm]   Encoders:
  [    0.596528] [drm]     TV1: INTERNAL_KLDSCP_DAC2
  [    0.596530] [drm] Connector 1:
  [    0.596531] [drm]   DVI-I-1
  [    0.596532] [drm]   HPD2
  [    0.596534] [drm]   DDC: 0x7e40 0x7e40 0x7e44 0x7e44 0x7e48 0x7e48 0x7e4c 0x7e4c
  [    0.596535] [drm]   Encoders:
  [    0.596536] [drm]     CRT1: INTERNAL_KLDSCP_DAC1
  [    0.596537] [drm]     DFP1: INTERNAL_UNIPHY
  [    0.596539] [drm] Connector 2:
  ...
  [    0.596540] [drm]   DVI-I-2
  [    0.596541] [drm]   HPD1
  [    0.596543] [drm]   DDC: 0x7e50 0x7e50 0x7e54 0x7e54 0x7e58 0x7e58 0x7e5c 0x7e5c
  [    0.596544] [drm]   Encoders:
  [    0.596545] [drm]     CRT2: INTERNAL_KLDSCP_DAC2
  [    0.596546] [drm]     DFP2: INTERNAL_KLDSCP_LVTMA
  [    0.596574] [drm] Internal thermal controller with fan control
  [    0.596605] [drm] radeon: power management initialized
  [    0.695710] [drm] fb mappable at 0xD0142000
  [    0.695712] [drm] vram apper at 0xD0000000
  [    0.695713] [drm] size 8294400
  [    0.695714] [drm] fb depth is 24
  [    0.695716] [drm]    pitch is 7680
  [    0.695779] fbcon: radeondrmfb (fb0) is primary device
  [    0.920023] usb 2-5: new high-speed USB device number 5 using ehci-pci
  [    0.924331] Console: switching to colour frame buffer device 210x65
  [    0.928594] radeon 0000:01:00.0: fb0: radeondrmfb frame buffer device
  [    0.928596] radeon 0000:01:00.0: registered panic notifier
  [    0.928601] [drm] Initialized radeon 2.34.0 20080528 for 0000:01:00.0 on minor 0
  ...
  [  343.872027] radeon 0000:01:00.0: GPU lockup CP stall for more than 10000msec
  [  343.872034] radeon 0000:01:00.0: GPU lockup (waiting for 0x0000000000000160)
  [  343.872039] radeon 0000:01:00.0: failed to get a new IB (-35)
  [  343.872042] [drm:radeon_cs_ib_chunk] *ERROR* Failed to get ib !
  [  343.873097] radeon 0000:01:00.0: Saved 2777 dwords of commands on ring 0.
  [  343.873106] radeon 0000:01:00.0: GPU softreset: 0x00000019
  [  343.873109] radeon 0000:01:00.0:   R_008010_GRBM_STATUS      = 0xA27334E0
  [  343.873112] radeon 0000:01:00.0:   R_008014_GRBM_STATUS2     = 0x00000103
  [  343.873114] radeon 0000:01:00.0:   R_000E50_SRBM_STATUS      = 0x200000C0
  [  343.873117] radeon 0000:01:00.0:   R_008674_CP_STALLED_STAT1 = 0x01000000
  [  343.873120] radeon 0000:01:00.0:   R_008678_CP_STALLED_STAT2 = 0x00001002
  [  343.873122] radeon 0000:01:00.0:   R_00867C_CP_BUSY_STAT     = 0x00028486
  [  343.873125] radeon 0000:01:00.0:   R_008680_CP_STAT          = 0x80838645
  [  343.873128] radeon 0000:01:00.0:   R_00D034_DMA_STATUS_REG   = 0x44C83D57
  [  343.943542] radeon 0000:01:00.0: R_008020_GRBM_SOFT_RESET=0x00007FEF
  [  343.943596] radeon 0000:01:00.0: SRBM_SOFT_RESET=0x00000100
  [  343.945684] radeon 0000:01:00.0:   R_008010_GRBM_STATUS      = 0xA0003030
  [  343.945687] radeon 0000:01:00.0:   R_008014_GRBM_STATUS2     = 0x00000003
  [  343.945689] radeon 0000:01:00.0:   R_000E50_SRBM_STATUS      = 0x200080C0
  [  343.945691] radeon 0000:01:00.0:   R_008674_CP_STALLED_STAT1 = 0x00000000
  [  343.945694] radeon 0000:01:00.0:   R_008678_CP_STALLED_STAT2 = 0x00000000
  [  343.945696] radeon 0000:01:00.0:   R_00867C_CP_BUSY_STAT     = 0x00000000
  [  343.945698] radeon 0000:01:00.0:   R_008680_CP_STAT          = 0x80100000
  [  343.945701] radeon 0000:01:00.0:   R_00D034_DMA_STATUS_REG   = 0x44C83D57
  [  343.945705] radeon 0000:01:00.0: GPU reset succeeded, trying to resume
  [  343.961937] [drm] PCIE gen 2 link speeds already enabled
  [  343.963722] [drm] PCIE GART of 512M enabled (table at 0x0000000000040000).
  [  343.963754] radeon 0000:01:00.0: WB enabled
  [  343.963757] radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000020000c00 and cpu addr 0xffff8801a3a0fc00
  [  343.963760] radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000020000c0c and cpu addr 0xffff8801a3a0fc0c
  [  343.994802] [drm] ring test on 0 succeeded in 1 usecs
  [  343.994860] [drm] ring test on 3 succeeded in 1 usecs
  [  344.155920] [drm] ib test on ring 0 succeeded in 0 usecs
  [  344.155947] [drm] ib test on ring 3 succeeded in 1 usecs
  [ 1188.775425] perf samples too long (2509 > 2500), lowering kernel.perf_event_max_sample_rate to 50000
  [ 4001.960037] radeon 0000:01:00.0: GPU lockup CP stall for more than 62004msec
  [ 4001.960044] radeon 0000:01:00.0: GPU lockup (waiting for 0x000000000000552a)
  [ 4001.960048] radeon 0000:01:00.0: failed to get a new IB (-35)
  [ 4001.960051] [drm:radeon_cs_ib_chunk] *ERROR* Failed to get ib !
  [ 4001.961092] radeon 0000:01:00.0: Saved 2009 dwords of commands on ring 0.
  [ 4001.961102] radeon 0000:01:00.0: GPU softreset: 0x00000019
  [ 4001.961106] radeon 0000:01:00.0:   R_008010_GRBM_STATUS      = 0xA27034E0
  [ 4001.961110] radeon 0000:01:00.0:   R_008014_GRBM_STATUS2     = 0x00000103
  [ 4001.961113] radeon 0000:01:00.0:   R_000E50_SRBM_STATUS      = 0x200000C0
  [ 4001.961117] radeon 0000:01:00.0:   R_008674_CP_STALLED_STAT1 = 0x01000000
  [ 4001.961120] radeon 0000:01:00.0:   R_008678_CP_STALLED_STAT2 = 0x00001002
  [ 4001.961123] radeon 0000:01:00.0:   R_00867C_CP_BUSY_STAT     = 0x00028486
  [ 4001.961127] radeon 0000:01:00.0:   R_008680_CP_STAT          = 0x80838645
  [ 4001.961130] radeon 0000:01:00.0:   R_00D034_DMA_STATUS_REG   = 0x44C83D57
  [ 4002.023122] radeon 0000:01:00.0: R_008020_GRBM_SOFT_RESET=0x00007FEF
  [ 4002.023177] radeon 0000:01:00.0: SRBM_SOFT_RESET=0x00000100
  [ 4002.025267] radeon 0000:01:00.0:   R_008010_GRBM_STATUS      = 0xA0003030
  [ 4002.025271] radeon 0000:01:00.0:   R_008014_GRBM_STATUS2     = 0x00000003
  [ 4002.025274] radeon 0000:01:00.0:   R_000E50_SRBM_STATUS      = 0x200080C0
  [ 4002.025277] radeon 0000:01:00.0:   R_008674_CP_STALLED_STAT1 = 0x00000000
  [ 4002.025281] radeon 0000:01:00.0:   R_008678_CP_STALLED_STAT2 = 0x00000000
  [ 4002.025284] radeon 0000:01:00.0:   R_00867C_CP_BUSY_STAT     = 0x00000000
  [ 4002.025288] radeon 0000:01:00.0:   R_008680_CP_STAT          = 0x80100000
  [ 4002.025291] radeon 0000:01:00.0:   R_00D034_DMA_STATUS_REG   = 0x44C83D57
  [ 4002.025297] radeon 0000:01:00.0: GPU reset succeeded, trying to resume
  [ 4002.041721] [drm] PCIE gen 2 link speeds already enabled
  [ 4002.043875] [drm] PCIE GART of 512M enabled (table at 0x0000000000040000).
  [ 4002.043918] radeon 0000:01:00.0: WB enabled
  [ 4002.043923] radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000020000c00 and cpu addr 0xffff8801a3a0fc00
  [ 4002.043927] radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000020000c0c and cpu addr 0xffff8801a3a0fc0c
  [ 4002.075013] [drm] ring test on 0 succeeded in 1 usecs
  [ 4002.075072] [drm] ring test on 3 succeeded in 1 usecs
  [ 4002.093977] [drm] ib test on ring 0 succeeded in 0 usecs
  [ 4002.094007] [drm] ib test on ring 3 succeeded in 1 usecs

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1290775/+subscriptions