Bug 94121

Summary: failed to train DP error when connecting external display
Product: Drivers Reporter: Vladimír Kriška (ujovlado)
Component: Video(DRI - Intel)Assignee: intel-gfx-bugs (intel-gfx-bugs)
Status: RESOLVED PATCH_ALREADY_AVAILABLE    
Severity: normal CC: intel-gfx-bugs
Priority: P1    
Hardware: All   
OS: Linux   
Kernel Version: 3.16.0-31-generic, 3.19.0-7-generic Subsystem:
Regression: No Bisected commit-id:
Attachments: dmesg log with debug mode 4 from newer kernel

Description Vladimír Kriška 2015-03-02 10:26:39 UTC 
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.
Comment 1 Vladimír Kriška 2015-03-02 12:46:15 UTC 
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.
Comment 2 Vladimír Kriška 2015-03-02 12:47:47 UTC 
Created attachment 168591 [details]
dmesg log with debug mode 4 from newer kernel
Comment 3 Vladimír Kriška 2015-04-02 22:50:36 UTC 
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.
Comment 4 Vladimír Kriška 2015-04-13 17:36:56 UTC 
No longer an issue. Looks like it was fixed by one of the libdrm* packages.

Si, I'm closing this.