Hi, since the last regression in 6.6.x was so popular I thought I'd post another one. :) The good news first: the symptoms described below do *not* reproduce with 6.7-rc5-git as of today (c8e97fc6b4c0), and there's an acceptable workaround for 6.6.x as well. The affected machine is an older SandyBridge dektop with a fanless r600 Redwood GPU, using the radeon driver. "Recently" - some time after the last few 6.6.x stable updates - it started to die with GPU lockups. I first blamed this on standby/resume - because why not? - but this turned out to be wrong; the real culprit is DPMS. I use xfce-power-manager as "screensaver" to turn off the display after inacitvity. This can be configured in two ways: "suspend" and "poweroff". I've been using "poweroff" since forever without problems, until now. The symptom is that everything works fine until the screensaver kicks in and tries to turn the monitor off, which sends the radeon driver and the GPU into a complete tailspin. Here is the GPU during boot - all good: Dec 12 12:47:54 ragnarok kernel: [drm] radeon kernel modesetting enabled. Dec 12 12:47:54 ragnarok kernel: Console: switching to colour dummy device 80x25 Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: vgaarb: deactivate vga console Dec 12 12:47:54 ragnarok kernel: [drm] initializing kernel modesetting (REDWOOD 0x1002:0x68DA 0x1043:0x0376 0x00). Dec 12 12:47:54 ragnarok kernel: ATOM BIOS: 68DA.12.19.0.3.AS01 Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: VRAM: 1024M 0x0000000000000000 - 0x000000003FFFFFFF (1024M used) Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: GTT: 1024M 0x0000000040000000 - 0x000000007FFFFFFF Dec 12 12:47:54 ragnarok kernel: [drm] Detected VRAM RAM=1024M, BAR=256M Dec 12 12:47:54 ragnarok kernel: [drm] RAM width 128bits DDR Dec 12 12:47:54 ragnarok kernel: [drm] radeon: 1024M of VRAM memory ready Dec 12 12:47:54 ragnarok kernel: [drm] radeon: 1024M of GTT memory ready. Dec 12 12:47:54 ragnarok kernel: [drm] Loading REDWOOD Microcode Dec 12 12:47:54 ragnarok kernel: [drm] Internal thermal controller without fan control Dec 12 12:47:54 ragnarok kernel: [drm] radeon: dpm initialized Dec 12 12:47:54 ragnarok kernel: [drm] GART: num cpu pages 262144, num gpu pages 262144 Dec 12 12:47:54 ragnarok kernel: [drm] enabling PCIE gen 2 link speeds, disable with radeon.pcie_gen2=0 Dec 12 12:47:54 ragnarok kernel: [drm] PCIE GART of 1024M enabled (table at 0x000000000014C000). Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: WB enabled Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000040000c00 Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000040000c0c Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: fence driver on ring 5 use gpu addr 0x000000000005c418 Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: radeon: MSI limited to 32-bit Dec 12 12:47:54 ragnarok kernel: radeon 0000:01:00.0: radeon: using MSI. Dec 12 12:47:54 ragnarok kernel: [drm] radeon: irq initialized. Dec 12 12:47:54 ragnarok kernel: [drm] ring test on 0 succeeded in 1 usecs Dec 12 12:47:54 ragnarok kernel: [drm] ring test on 3 succeeded in 2 usecs Dec 12 12:47:54 ragnarok kernel: [drm] ring test on 5 succeeded in 1 usecs Dec 12 12:47:54 ragnarok kernel: [drm] UVD initialized successfully. Dec 12 12:47:54 ragnarok kernel: [drm] ib test on ring 0 succeeded in 0 usecs Dec 12 12:47:54 ragnarok kernel: [drm] ib test on ring 3 succeeded in 0 usecs Dec 12 12:47:55 ragnarok kernel: [drm] ib test on ring 5 succeeded Dec 12 12:47:55 ragnarok kernel: [drm] Radeon Display Connectors Dec 12 12:47:55 ragnarok kernel: [drm] Connector 0: Dec 12 12:47:55 ragnarok kernel: [drm] HDMI-A-1 Dec 12 12:47:55 ragnarok kernel: [drm] HPD2 Dec 12 12:47:55 ragnarok kernel: [drm] DDC: 0x6450 0x6450 0x6454 0x6454 0x6458 0x6458 0x645c 0x645c Dec 12 12:47:55 ragnarok kernel: [drm] Encoders: Dec 12 12:47:55 ragnarok kernel: [drm] DFP1: INTERNAL_UNIPHY2 Dec 12 12:47:55 ragnarok kernel: [drm] Connector 1: Dec 12 12:47:55 ragnarok kernel: [drm] DVI-I-1 Dec 12 12:47:55 ragnarok kernel: [drm] HPD1 Dec 12 12:47:55 ragnarok kernel: [drm] DDC: 0x6460 0x6460 0x6464 0x6464 0x6468 0x6468 0x646c 0x646c Dec 12 12:47:55 ragnarok kernel: [drm] Encoders: Dec 12 12:47:55 ragnarok kernel: [drm] DFP2: INTERNAL_UNIPHY1 Dec 12 12:47:55 ragnarok kernel: [drm] CRT1: INTERNAL_KLDSCP_DAC1 Dec 12 12:47:55 ragnarok kernel: [drm] Connector 2: Dec 12 12:47:55 ragnarok kernel: [drm] VGA-1 Dec 12 12:47:55 ragnarok kernel: [drm] DDC: 0x6470 0x6470 0x6474 0x6474 0x6478 0x6478 0x647c 0x647c Dec 12 12:47:55 ragnarok kernel: [drm] Encoders: Dec 12 12:47:55 ragnarok kernel: [drm] CRT2: INTERNAL_KLDSCP_DAC2 Dec 12 12:47:55 ragnarok kernel: [drm] Initialized radeon 2.50.0 20080528 for 0000:01:00.0 on minor 0 Dec 12 12:47:55 ragnarok kernel: [drm] fb mappable at 0xE034D000 Dec 12 12:47:55 ragnarok kernel: [drm] vram apper at 0xE0000000 Dec 12 12:47:55 ragnarok kernel: [drm] size 9216000 Dec 12 12:47:55 ragnarok kernel: [drm] fb depth is 24 Dec 12 12:47:55 ragnarok kernel: [drm] pitch is 7680 Dec 12 12:47:55 ragnarok kernel: fbcon: radeondrmfb (fb0) is primary device Dec 12 12:47:55 ragnarok kernel: Console: switching to colour frame buffer device 240x75 Dec 12 12:47:55 ragnarok kernel: radeon 0000:01:00.0: [drm] fb0: radeondrmfb frame buffer device Eventually the screensaver tries to switch off the monitor via DPMS "poweroff" method and this greatly upsets the GPU: Dec 12 20:39:59 ragnarok kernel: radeon 0000:01:00.0: ring 0 stalled for more than 10140msec Dec 12 20:39:59 ragnarok kernel: radeon 0000:01:00.0: GPU lockup (current fence id 0x0000000000000002 last fence id 0x0000000000000003 on ring 0) The above repeats many times until: Dec 12 20:40:18 ragnarok kernel: radeon 0000:01:00.0: GPU lockup (current fence id 0x0000000000000002 last fence id 0x0000000000000003 on ring 0) Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: Saved 55 dwords of commands on ring 0. Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GPU softreset: 0x00000008 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_STATUS = 0xA0003828 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_STATUS_SE0 = 0x00000007 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_STATUS_SE1 = 0x00000007 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: SRBM_STATUS = 0x200000C0 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: SRBM_STATUS2 = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_008674_CP_STALLED_STAT1 = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_008678_CP_STALLED_STAT2 = 0x00010100 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_00867C_CP_BUSY_STAT = 0x00020180 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_008680_CP_STAT = 0x80038042 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_00D034_DMA_STATUS_REG = 0x44C83D57 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_SOFT_RESET=0x00004001 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: SRBM_SOFT_RESET=0x00000100 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_STATUS = 0x00003828 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_STATUS_SE0 = 0x00000007 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GRBM_STATUS_SE1 = 0x00000007 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: SRBM_STATUS = 0x200000C0 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: SRBM_STATUS2 = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_008674_CP_STALLED_STAT1 = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_008678_CP_STALLED_STAT2 = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_00867C_CP_BUSY_STAT = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_008680_CP_STAT = 0x00000000 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: R_00D034_DMA_STATUS_REG = 0x44C83D57 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: GPU reset succeeded, trying to resume Dec 12 20:40:19 ragnarok kernel: [drm] enabling PCIE gen 2 link speeds, disable with radeon.pcie_gen2=0 Dec 12 20:40:19 ragnarok kernel: [drm] PCIE GART of 1024M enabled (table at 0x000000000014C000). Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: WB enabled Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: fence driver on ring 0 use gpu addr 0x0000000040000c00 Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: fence driver on ring 3 use gpu addr 0x0000000040000c0c Dec 12 20:40:19 ragnarok kernel: radeon 0000:01:00.0: fence driver on ring 5 use gpu addr 0x000000000005c418 Dec 12 20:40:19 ragnarok kernel: debugfs: File 'radeon_ring_gfx' in directory '0' already present! Dec 12 20:40:19 ragnarok kernel: debugfs: File 'radeon_ring_dma1' in directory '0' already present! Dec 12 20:40:19 ragnarok kernel: [drm:r600_ring_test [radeon]] *ERROR* radeon: ring 0 test failed (scratch(0x8504)=0xCAFEDEAD) Dec 12 20:40:19 ragnarok kernel: [drm:evergreen_resume [radeon]] *ERROR* evergreen startup failed on resume Dec 12 20:40:29 ragnarok kernel: radeon 0000:01:00.0: ring 0 stalled for more than 10077msec Dec 12 20:40:29 ragnarok kernel: radeon 0000:01:00.0: GPU lockup (current fence id 0x0000000000000002 last fence id 0x0000000000000003 on ring 0) ..at which point I have to poweroff the entire machine to reset the GPU; a simple reboot does not help. It took me a while to find the culprit (the DPMS poweroff method), and for now my workaround is to switch xfce-power-manager to use the "suspend" method instead. This has been working reliably for several days now, with many system suspend/resume and display suspend/wakeup cycles. I *think* this started to happen with 6.6.5, which had a lot of drm-amd-display patches (see[1]), so before I start bisecting and whatnot I was wondering if anybody has any suggestions what might be the cause here. I can gladly test additional patches or reverts. Even if 6.7-rc seems to be OK again I still think it's worthwile to fix this in 6.6 since it's an LTS kernel. Thanks for reading! Holger [1] https://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/queue-6.6?id=3601ed703d11a9140852b279482666d6f53e1c06
