On Mon, 08 May 2017, Andrew Siplas <andrew@xxxxxxxx> wrote: > At Xorg startup after a fresh compile of the mainline kernel, WARN_ON is > truthy and throws a warning into the kernel's dmesg buffer. Please file a bug at [1], add drm.debug=14 module parameter, add dmesg from boot to reproducing the problem. BR, Jani. [1] https://bugs.freedesktop.org/enter_bug.cgi?product=DRI&component=DRM/Intel > > I'm still trying to understand the driver, but it originates here: > > -- > > static void vlv_disable_backlight(struct intel_connector *connector) > { > struct drm_i915_private *dev_priv = > to_i915(connector->base.dev); > enum pipe pipe = intel_get_pipe_from_connector(connector); > u32 tmp; > > if (WARN_ON(pipe != PIPE_A && pipe != PIPE_B)) > return; > > intel_panel_actually_set_backlight(connector, 0); > > tmp = I915_READ(VLV_BLC_PWM_CTL2(pipe)); > I915_WRITE(VLV_BLC_PWM_CTL2(pipe), tmp & ~BLM_PWM_ENABLE); > } > > -- > > Don't know yet what this means and so taking a chance this warning is > something someone here might have some insight into / want to know about > especially given the "...----[ cut here ]----...". > > The last two lines are from 5+ minutes after the warning but seem related: > > > [ 67.896233] ------------[ cut here ]------------ > [ 67.896259] WARNING: CPU: 1 PID: 4276 at drivers/gpu/drm/i915/intel_panel.c:771 vlv_disable_backlight+0x86/0x90 > [ 67.896261] Modules linked in: iptable_nat nf_nat_ipv4 nf_nat uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_v4l2 videobuf2_core videodev > [ 67.896299] CPU: 1 PID: 4276 Comm: Xorg Not tainted 4.11.0+ #2 > [ 67.896303] Hardware name: HP HP Notebook/80C5, BIOS F.1E 12/25/2015 > [ 67.896308] task: ffff8d6e75d79800 task.stack: ffff9a06c1218000 > [ 67.896318] RIP: 0010:vlv_disable_backlight+0x86/0x90 > [ 67.896323] RSP: 0018:ffff9a06c121b998 EFLAGS: 00010286 > [ 67.896330] RAX: 0000000000000029 RBX: ffff8d6e76018000 RCX: ffffffff8ea56a78 > [ 67.896335] RDX: 0000000000000001 RSI: 0000000000000092 RDI: ffffffff8ece6bcc > [ 67.896339] RBP: ffff9a06c121b9b0 R08: 0000000000000029 R09: 00000000000002d8 > [ 67.896344] R10: 0000000000000000 R11: 0000000000000320 R12: ffff8d6e723c5000 > [ 67.896348] R13: 00000000ffffffff R14: ffff8d6e7423e800 R15: ffff8d6e74ab9830 > [ 67.896355] FS: 00007fb8d7e00a40(0000) GS:ffff8d6e7fc80000(0000) knlGS:0000000000000000 > [ 67.896359] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > [ 67.896364] CR2: 0000557bfe77dfd0 CR3: 0000000274d31000 CR4: 00000000001006e0 > [ 67.896368] Call Trace: > [ 67.896383] intel_panel_disable_backlight+0x51/0x80 > [ 67.896391] intel_edp_backlight_off+0x42/0x50 > [ 67.896397] intel_disable_dp+0x70/0xf0 > [ 67.896407] intel_encoders_disable.isra.103+0x82/0x90 > [ 67.896416] i9xx_crtc_disable+0x51/0x3b0 > [ 67.896424] ? intel_crtc_disable_planes+0xd4/0xf0 > [ 67.896434] intel_atomic_commit_tail+0x892/0xfb0 > [ 67.896444] ? insert_work+0x52/0x70 > [ 67.896453] ? __queue_work+0x12e/0x390 > [ 67.896461] ? intel_atomic_commit_ready+0x70/0x80 > [ 67.896470] intel_atomic_commit+0x3e6/0x4b0 > [ 67.896479] ? handle_conflicting_encoders+0x279/0x290 > [ 67.896489] drm_atomic_commit+0x46/0x50 > [ 67.896497] drm_atomic_helper_set_config+0x6b/0xa0 > [ 67.896507] __drm_mode_set_config_internal+0x62/0x110 > [ 67.896514] drm_mode_setcrtc+0x4ba/0x5a0 > [ 67.896524] drm_ioctl+0x326/0x430 > [ 67.896532] ? drm_mode_getcrtc+0x170/0x170 > [ 67.896543] do_vfs_ioctl+0x8f/0x5a0 > [ 67.896552] ? getnstimeofday64+0x9/0x20 > [ 67.896561] SyS_ioctl+0x74/0x80 > [ 67.896569] do_syscall_64+0x48/0xb0 > [ 67.896580] entry_SYSCALL64_slow_path+0x25/0x25 > [ 67.896586] RIP: 0033:0x7fb8d5932507 > [ 67.896590] RSP: 002b:00007ffe8bf43018 EFLAGS: 00003246 ORIG_RAX: 0000000000000010 > [ 67.896598] RAX: ffffffffffffffda RBX: 0000561b92c11210 RCX: 00007fb8d5932507 > [ 67.896602] RDX: 00007ffe8bf43140 RSI: 00000000c06864a2 RDI: 0000000000000009 > [ 67.896607] RBP: 00007ffe8bf43140 R08: 0000561b92c11050 R09: 0000000000000001 > [ 67.896611] R10: 0000000000000001 R11: 0000000000003246 R12: 00000000c06864a2 > [ 67.896615] R13: 0000000000000009 R14: 0000561b92c13f70 R15: 00007fb8d7d67000 > [ 67.896620] Code: df 41 8d b4 05 50 12 06 00 ff 93 f8 06 00 00 5b 41 5c 41 5d 5d c3 48 c7 c6 18 bc 88 8e 48 c7 c7 22 e8 82 8e 31 c0 e8 47 70 b6 ff <0f> ff eb e0 66 0f 1f 44 00 00 55 8b b7 f4 03 00 00 48 89 e5 e8 > [ 67.896771] ---[ end trace 528f42628325fc1b ]--- > [ 490.370803] [drm] Atomic update on pipe (A) took 102 us, max time under evasion is 100 us > [ 2623.216311] [drm] Atomic update on pipe (A) took 415 us, max time under evasion is 100 us > > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Jani Nikula, Intel Open Source Technology Center _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
