Created attachment 164481 [details] This is the kern.log backtrace I configure and compile many time the Linux vanilla kernel. synce the first time i recompile the kernel I get the display go off and soon go on after logging in my debian. Now, after 3.18 kernel version, i note that syslog put this error: [drm:i9xx_check_fifo_underruns] *ERROR* pipe A underrun I put the backtrace. My CPU is an Intel U4100 an dual core Cantiga i think. My graphic card is clearly an Intel Integrated If I dmesg |grep vga : [ 0.197091] vgaarb: setting as boot device: PCI:0000:00:02.0 [ 0.197091] vgaarb: device added: PCI:0000:00:02.0,decodes=io+mem,owns=io+mem,locks=none [ 0.197091] vgaarb: loaded [ 0.197091] vgaarb: bridge control possible 0000:00:02.0 [ 0.344654] vgaarb: device changed decodes: PCI:0000:00:02.0,olddecodes=io+mem,decodes=io+mem:owns=io+mem .
Please add drm.debug=14 module parameter and attach dmesg from boot to the problem.
Created attachment 164781 [details] Debug log with option drm.debug=14
(In reply to Jani Nikula from comment #1) > Please add drm.debug=14 module parameter and attach dmesg from boot to the > problem. Ok I do it.
The dmesg indicates no problems. Were you able to reproduce the issue?
Created attachment 166551 [details] Kernel with DEBUG option drm.debug=14
Yes, I'm able to reproduce the bug every time I log in. I use use the command $dmesg |grep drm $ so i did the mistake. I fully repost the syslog file names kern.log.
Feb 12 09:54:53 kernel: [ 21.980050] WARNING: CPU: 1 PID: 2825 at drivers/gpu/drm/i915/intel_display.c:901 intel_tv_detect+0x260/0x5b0() Feb 12 09:54:53 kernel: [ 21.980053] vblank wait on pipe B timed out Feb 12 09:54:53 kernel: [ 21.980055] Modules linked in: cpufreq_stats iptable_filter ip_tables binfmt_misc uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core sd_mod Feb 12 09:54:53 kernel: [ 21.980072] CPU: 1 PID: 2825 Comm: Xorg Not tainted 3.18.1-0.6 #9 Feb 12 09:54:53 kernel: [ 21.980075] Hardware name: SAMSUNG ELECTRONICS CO., LTD. X120/X170/X171 /X120/X170/X171 , BIOS 08CX.M010.20100408.KSY 04/08/2010 Feb 12 09:54:53 kernel: [ 21.980078] 0000000000000000 0000000000000009 ffffffff817d2ae3 ffff8800b918fad8 Feb 12 09:54:53 kernel: [ 21.980083] ffffffff81049866 ffff8800b9313000 ffff8800b9360000 ffff8800b93df800 Feb 12 09:54:53 kernel: [ 21.980087] 00000000c00c00d0 0000000030000000 ffffffff81049945 ffffffff81a272a8 Feb 12 09:54:53 kernel: [ 21.980092] Call Trace: Feb 12 09:54:53 kernel: [ 21.980100] [<ffffffff817d2ae3>] ? dump_stack+0x41/0x51 Feb 12 09:54:53 kernel: [ 21.980107] [<ffffffff81049866>] ? warn_slowpath_common+0x86/0xb0 Feb 12 09:54:53 kernel: [ 21.980112] [<ffffffff81049945>] ? warn_slowpath_fmt+0x45/0x50 Feb 12 09:54:53 kernel: [ 21.980118] [<ffffffff8143483e>] ? intel_wait_for_vblank+0x19e/0x1f0 Feb 12 09:54:53 kernel: [ 21.980122] [<ffffffff814706a0>] ? intel_tv_detect+0x260/0x5b0 Feb 12 09:54:53 kernel: [ 21.980129] [<ffffffff813b330a>] ? drm_helper_probe_single_connector_modes_merge_bits+0x2fa/0x3f0 Feb 12 09:54:53 kernel: [ 21.980135] [<ffffffff813ce205>] ? drm_mode_getconnector+0x3b5/0x430 Feb 12 09:54:53 kernel: [ 21.980141] [<ffffffff813c0b24>] ? drm_ioctl+0x1c4/0x5d0 Feb 12 09:54:53 kernel: [ 21.980145] [<ffffffff813cde50>] ? drm_mode_getcrtc+0xe0/0xe0 Feb 12 09:54:53 kernel: [ 21.980151] [<ffffffff811645ee>] ? do_vfs_ioctl+0x7e/0x500 Feb 12 09:54:53 kernel: [ 21.980156] [<ffffffff810020ef>] ? restore_sigcontext+0x13f/0x150 Feb 12 09:54:53 kernel: [ 21.980161] [<ffffffff81057d20>] ? restore_altstack+0x10/0x30 Feb 12 09:54:53 kernel: [ 21.980165] [<ffffffff81164b09>] ? SyS_ioctl+0x99/0xb0 Feb 12 09:54:53 kernel: [ 21.980170] [<ffffffff817db299>] ? stub_rt_sigreturn+0x69/0xa0 Feb 12 09:54:53 kernel: [ 21.980175] [<ffffffff817dac96>] ? system_call_fastpath+0x16/0x1b
*** This bug has been marked as a duplicate of bug 86771 ***