I ran into the same issue on a Lenovo T420 with 01:00.0 VGA compatible controller: NVIDIA Corporation GF119M [Quadro NVS 4200M] (rev a1).

As soon as I plug an external monitor via DP, Nouveau oopses at nvkm_dp_train_drive(). If I try to boot with the monitor plugged in the system doesn't boot at all. I attached the relevant log at the end.

The external monitor works perfectly on 4.12.9-300.fc26.x86_64 and breaks on 4.13.1-301.fc27.x86_64, the commit mentioned in this issue was introduced between these two version.


Dec 25 01:41:47 localhost gnome-shell[1662]: Failed to apply DRM plane transform 0: Invalid argument
Dec 25 01:41:47 localhost gnome-shell[1662]: Failed to apply DRM plane transform 0: Invalid argument
Dec 25 01:41:48 localhost gnome-shell[1662]: JS WARNING: [resource:///org/gnome/shell/ui/workspaceThumbnail.js 892]: reference to undefined property "_switchWorkspaceNotifyId"
Dec 25 01:41:48 localhost gsd-color[1301]: no xrandr-Dell Inc.-DELL U2415-7MT0167S57AS device found: Failed to find output xrandr-Dell Inc.-DELL U2415-7MT0167S57AS
Dec 25 01:41:48 localhost kernel: BUG: unable to handle kernel NULL pointer dereference at           (null)
Dec 25 01:41:48 localhost kernel: IP:           (null)
Dec 25 01:41:48 localhost kernel: PGD 0 
Dec 25 01:41:48 localhost kernel: P4D 0 
Dec 25 01:41:48 localhost kernel: 
Dec 25 01:41:48 localhost kernel: Oops: 0010 [#1] SMP
Dec 25 01:41:48 localhost kernel: Modules linked in: rfcomm fuse ccm nf_conntrack_netbios_ns nf_conntrack_broadcast xt_CT ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_conntrack ip_set nfnetlink ebtable_nat ebtable_broute bridge stp llc ip6table_nat nf_conntrack_ipv6 nf_defrag_ipv6 nf_nat_ipv6 ip6table_mangle ip6table_raw ip6table_security iptable_nat nf_conntrack_ipv4 nf_defrag_ipv4 nf_nat_ipv4 nf_nat nf_conntrack libcrc32c iptable_mangle iptable_raw iptable_security ebtable_filter ebtables ip6table_filter ip6_tables bnep sunrpc vfat fat intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm iTCO_wdt iTCO_vendor_support mei_wdt irqbypass intel_cstate intel_uncore intel_rapl_perf arc4 joydev wmi_bmof uvcvideo iwldvm btusb btrtl mac80211 btbcm btintel bluetooth videobuf2_vmalloc videobuf2_memops videobuf2_v4l2
Dec 25 01:41:48 localhost kernel:  videobuf2_core videodev snd_hda_codec_hdmi i2c_i801 thinkpad_acpi media iwlwifi lpc_ich snd_hda_codec_conexant snd_hda_codec_generic mei_me snd_hda_intel ecdh_generic mei snd_hda_codec cfg80211 snd_hda_core snd_hwdep snd_seq snd_seq_device snd_pcm snd_timer snd shpchp tpm_tis soundcore tpm_tis_core tpm rfkill dm_crypt nouveau crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel serio_raw mxm_wmi i2c_algo_bit drm_kms_helper sdhci_pci ttm sdhci e1000e mmc_core drm ptp pps_core wmi video
Dec 25 01:41:48 localhost kernel: CPU: 0 PID: 68 Comm: kworker/u16:1 Not tainted 4.13.1-301.fc27.x86_64 #1
Dec 25 01:41:48 localhost kernel: Hardware name: LENOVO 4180PC4/4180PC4, BIOS 83ET76WW (1.46 ) 07/05/2013
Dec 25 01:41:48 localhost kernel: Workqueue: nvkm-disp gf119_disp_super [nouveau]
Dec 25 01:41:48 localhost kernel: task: ffff8f14901b8000 task.stack: ffffa0d8c1250000
Dec 25 01:41:48 localhost kernel: RIP: 0010:          (null)
Dec 25 01:41:48 localhost kernel: RSP: 0018:ffffa0d8c1253c10 EFLAGS: 00010206
Dec 25 01:41:48 localhost kernel: RAX: ffffffffc03b5ee0 RBX: 0000000000000000 RCX: 0000000000000016
Dec 25 01:41:48 localhost kernel: RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffff8f148f0fe720
Dec 25 01:41:48 localhost kernel: RBP: ffffa0d8c1253c98 R08: 0000000000000000 R09: 0000000000000000
Dec 25 01:41:48 localhost kernel: R10: 0000000000000000 R11: 0000000000001000 R12: 0000000000000000
Dec 25 01:41:48 localhost kernel: R13: 0000000000000000 R14: ffff8f148fd90800 R15: ffffa0d8c1253d38
Dec 25 01:41:48 localhost kernel: FS:  0000000000000000(0000) GS:ffff8f149dc00000(0000) knlGS:0000000000000000
Dec 25 01:41:48 localhost kernel: CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
Dec 25 01:41:48 localhost kernel: CR2: 0000000000000000 CR3: 0000000122e09000 CR4: 00000000000406f0
Dec 25 01:41:48 localhost kernel: Call Trace:
Dec 25 01:41:48 localhost kernel:  ? nvkm_dp_train_drive+0x183/0x2c0 [nouveau]
Dec 25 01:41:48 localhost kernel:  nvkm_dp_acquire+0x4f3/0xcd0 [nouveau]
Dec 25 01:41:48 localhost kernel:  nv50_disp_super_2_2+0x5d/0x470 [nouveau]
Dec 25 01:41:48 localhost kernel:  ? nvkm_devinit_pll_set+0xf/0x20 [nouveau]
Dec 25 01:41:48 localhost kernel:  gf119_disp_super+0x19c/0x2f0 [nouveau]
Dec 25 01:41:48 localhost kernel:  process_one_work+0x193/0x3c0
Dec 25 01:41:48 localhost kernel:  worker_thread+0x4a/0x3a0
Dec 25 01:41:48 localhost kernel:  kthread+0x125/0x140
Dec 25 01:41:48 localhost kernel:  ? process_one_work+0x3c0/0x3c0
Dec 25 01:41:48 localhost kernel:  ? kthread_park+0x60/0x60
Dec 25 01:41:48 localhost kernel:  ret_from_fork+0x25/0x30
Dec 25 01:41:48 localhost kernel: Code:  Bad RIP value.
Dec 25 01:41:48 localhost kernel: RIP:           (null) RSP: ffffa0d8c1253c10
Dec 25 01:41:48 localhost kernel: CR2: 0000000000000000
Dec 25 01:41:48 localhost kernel: ---[ end trace 9a99aaab375d014e ]---
Dec 25 01:41:50 localhost abrt-dump-journal-oops[942]: abrt-dump-journal-oops: Found oopses: 1
Dec 25 01:41:50 localhost abrt-dump-journal-oops[942]: abrt-dump-journal-oops: Creating problem directories
Dec 25 01:41:50 localhost kernel: nouveau 0000:01:00.0: DRM: EVO timeout
Dec 25 01:41:51 localhost abrt-notification[2289]: System encountered a non-fatal error in nvkm_dp_train_drive()
Dec 25 01:41:52 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:41:54 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:41:56 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:41:58 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:00 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:02 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:04 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:06 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:08 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:10 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:12 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:14 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:16 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:18 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout
Dec 25 01:42:20 localhost kernel: nouveau 0000:01:00.0: DRM: base-1: timeout