Hi, on new laptop (Thinkpad 450s) there's problem connecting external display throught DP. When you connect DP cable, you'll get following error: [drm:intel_dp_complete_link_train] *ERROR* failed to train DP, aborting After DP cable removal, desktop theme is switched to default/no-theme. (this is not a big deal here, I want only mention - maybe it helps). Here's output from dmesg: [ 2166.924182] ------------[ cut here ]------------ [ 2166.924201] WARNING: CPU: 1 PID: 376 at /build/buildd/linux-3.16.0/drivers/gpu/drm/i915/intel_dp.c:3129 intel_dp_link_down+0x1a9/0x230 [i915]() [ 2166.924202] Modules linked in: ctr ccm pci_stub vboxpci(OE) vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) arc4 rfcomm bnep bluetooth 6lowpan_iphc iwlmvm mac80211 intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm joydev serio_raw lpc_ich cdc_mbim rtsx_pci_ms memstick cdc_ncm usbnet mii cdc_wdm cdc_acm iwlwifi cfg80211 snd_seq_midi snd_seq_midi_event snd_rawmidi snd_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel snd_hda_controller snd_hda_codec snd_hwdep snd_seq snd_pcm thinkpad_acpi nvram snd_seq_device parport_pc snd_timer ppdev snd mei_me shpchp mei mac_hid soundcore lp parport dm_crypt hid_generic usbhid hid uas usb_storage rtsx_pci_sdmmc crct10dif_pclmul crc32_pclmul ghash_clmulni_intel aesni_intel aes_x86_64 lrw gf128mul glue_helper ablk_helper i915 [ 2166.924240] cryptd psmouse ahci e1000e libahci i2c_algo_bit rtsx_pci drm_kms_helper ptp pps_core drm wmi video [ 2166.924248] CPU: 1 PID: 376 Comm: kworker/1:2 Tainted: G W OE 3.16.0-31-generic #41-Ubuntu [ 2166.924249] Hardware name: LENOVO 20BX001YXS/20BX001YXS, BIOS JBET39WW (1.04 ) 12/09/2014 [ 2166.924262] Workqueue: events i915_hotplug_work_func [i915] [ 2166.924264] 0000000000000009 ffff880327d6fa08 ffffffff81782d0b 0000000000000000 [ 2166.924267] ffff880327d6fa40 ffffffff8106ff2d ffff8803272a0000 0000000083000006 [ 2166.924269] ffff880036007000 0000000000000001 ffff880327fce0d8 ffff880327d6fa50 [ 2166.924272] Call Trace: [ 2166.924276] [<ffffffff81782d0b>] dump_stack+0x45/0x56 [ 2166.924280] [<ffffffff8106ff2d>] warn_slowpath_common+0x7d/0xa0 [ 2166.924283] [<ffffffff8107000a>] warn_slowpath_null+0x1a/0x20 [ 2166.924299] [<ffffffffc02e03f9>] intel_dp_link_down+0x1a9/0x230 [i915] [ 2166.924315] [<ffffffffc02e58d5>] intel_dp_complete_link_train+0x105/0x390 [i915] [ 2166.924331] [<ffffffffc02dd8e8>] intel_ddi_pre_enable+0x1a8/0x1f0 [i915] [ 2166.924347] [<ffffffffc02c64dc>] haswell_crtc_enable+0x3ac/0xa30 [i915] [ 2166.924362] [<ffffffffc02c9a60>] __intel_set_mode+0x830/0xab0 [i915] [ 2166.924377] [<ffffffffc02ccc36>] intel_set_mode+0x16/0x30 [i915] [ 2166.924391] [<ffffffffc02cdcfa>] intel_crtc_set_config+0xa4a/0xda0 [i915] [ 2166.924394] [<ffffffff810a2919>] ? ttwu_do_wakeup+0x19/0xd0 [ 2166.924407] [<ffffffffc018e6d1>] drm_mode_set_config_internal+0x61/0xe0 [drm] [ 2166.924413] [<ffffffffc01cfad3>] restore_fbdev_mode+0xb3/0xe0 [drm_kms_helper] [ 2166.924419] [<ffffffffc01d15d5>] drm_fb_helper_restore_fbdev_mode_unlocked+0x25/0x70 [drm_kms_helper] [ 2166.924425] [<ffffffffc01d1642>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper] [ 2166.924430] [<ffffffffc01d155f>] drm_fb_helper_hotplug_event+0x8f/0xe0 [drm_kms_helper] [ 2166.924446] [<ffffffffc02d824e>] intel_fbdev_output_poll_changed+0x1e/0x30 [i915] [ 2166.924452] [<ffffffffc01ce497>] drm_kms_helper_hotplug_event+0x27/0x30 [drm_kms_helper] [ 2166.924466] [<ffffffffc02a30b9>] i915_hotplug_work_func+0x259/0x340 [i915] [ 2166.924469] [<ffffffff8108dab2>] process_one_work+0x182/0x4e0 [ 2166.924471] [<ffffffff8108de7b>] worker_thread+0x6b/0x6a0 [ 2166.924474] [<ffffffff8108de10>] ? process_one_work+0x4e0/0x4e0 [ 2166.924477] [<ffffffff81094cfb>] kthread+0xdb/0x100 [ 2166.924480] [<ffffffff81094c20>] ? kthread_create_on_node+0x1c0/0x1c0 [ 2166.924484] [<ffffffff8178ac7c>] ret_from_fork+0x7c/0xb0 [ 2166.924487] [<ffffffff81094c20>] ? kthread_create_on_node+0x1c0/0x1c0 [ 2166.924488] ---[ end trace aed324c6757a8f8b ]--- [ 2166.926788] [drm:intel_dp_complete_link_train] *ERROR* failed to train DP, aborting Also, I could provide additional information if it helps.
I upgraded to last kernel. I have installed 3.19.0-031900-generic from http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.19-vivid/. Problem still persists, error message is almost the same: [drm:intel_dp_complete_link_train [i915]] *ERROR* failed to train DP, aborting and I didn't get trace, so I set debug mode to 4 in /sys/module/drm/parameters/debug and output is attached - 3.19.0-031900-generic-dmesg.log.
Created attachment 168591 [details] dmesg log with debug mode 4 from newer kernel
I just tested with drm-intel-nightly/2015-04-02-vivid and problem is still there. Should I provide any information from this build for better debugging? Thanks.
No longer an issue. Looks like it was fixed by one of the libdrm* packages. Si, I'm closing this.