now I can switch the disk between working and broken computers, I can provide logs... here is the last 100 lines of kern.log with 2.17-rc7: Mar 3 22:08:10 alu kernel: [ 185.523286] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.147354] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.148362] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.374531] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.375536] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.389098] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.390110] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.405736] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.406737] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.735683] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.736609] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.756004] [drm] DC: Cursor address is 0! Mar 3 22:08:16 alu kernel: [ 191.757035] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.327221] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.328229] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.582181] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.583143] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.588987] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.589997] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.605801] [drm] DC: Cursor address is 0! Mar 3 22:08:22 alu kernel: [ 197.606811] [drm] DC: Cursor address is 0! Mar 3 22:08:23 alu kernel: [ 197.926448] [drm] DC: Cursor address is 0! Mar 3 22:08:23 alu kernel: [ 197.927348] [drm] DC: Cursor address is 0! Mar 3 22:08:23 alu kernel: [ 197.938932] [drm] DC: Cursor address is 0! Mar 3 22:08:23 alu kernel: [ 197.939960] [drm] DC: Cursor address is 0! Mar 3 22:08:28 alu kernel: [ 203.542948] [drm] DC: Cursor address is 0! Mar 3 22:08:28 alu kernel: [ 203.543955] [drm] DC: Cursor address is 0! Mar 3 22:17:09 alu kernel: [ 724.826820] sdd: sdd1 sdd2 sdd3 Mar 4 08:23:55 alu kernel: [37130.167508] [drm] DC: Cursor address is 0! Mar 4 08:23:55 alu kernel: [37130.168529] [drm] DC: Cursor address is 0! Mar 4 08:24:00 alu kernel: [37135.194254] [drm] DC: Cursor address is 0! Mar 4 08:24:00 alu kernel: [37135.195262] [drm] DC: Cursor address is 0! Mar 4 08:24:01 alu kernel: [37136.136335] [drm] DC: Cursor address is 0! Mar 4 08:24:01 alu kernel: [37136.137343] [drm] DC: Cursor address is 0! Mar 4 08:24:06 alu kernel: [37141.159515] [drm] DC: Cursor address is 0! Mar 4 08:24:06 alu kernel: [37141.160539] [drm] DC: Cursor address is 0! Mar 4 15:02:12 alu kernel: [61027.919361] [drm] TOSHIBA-TV: [Block 0] Mar 4 15:02:12 alu kernel: [61027.919366] [drm] TOSHIBA-TV: [Block 1] Mar 4 15:02:12 alu kernel: [61027.920051] [drm] dc_link_detect: manufacturer_id = 6252, product_id = 210, serial_number = 1010101, manufacture_week = 255, manufacture_year = 23, display_name = TOSHIBA-TV, speaker_flag = 5, audio_mode_count = 2 Mar 4 15:02:12 alu kernel: [61027.921500] [drm] dc_link_detect: mode number = 0, format_code = 1, channel_count = 1, sample_rate = 7, sample_size = 7 Mar 4 15:02:12 alu kernel: [61027.922339] [drm] dc_link_detect: mode number = 1, format_code = 2, channel_count = 5, sample_rate = 7, sample_size = 80 Mar 4 15:02:12 alu kernel: [61027.924286] [drm:generic_reg_wait [amdgpu]] *ERROR* REG_WAIT timeout 1us * 100 tries - tgn10_lock line:566 Mar 4 15:02:12 alu kernel: [61027.925286] WARNING: CPU: 4 PID: 12416 at /build/linux-LuqUgo/linux-4.15.0/drivers/gpu/drm/amd/amdgpu/../display/dc/dc_helper.c:190 generic_reg_wait+0xe8/0x120 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.926314] Modules linked in: binfmt_misc eeepc_wmi asus_wmi snd_hda_codec_realtek wmi_bmof sparse_keymap mxm_wmi snd_hda_codec_generic snd_hda_codec_hdmi snd_hda_intel edac_mce_amd kvm_amd snd_hda_codec kvm irqbypass snd_hda_core snd_hwdep crct10dif_pclmul crc32_pclmul snd_pcm ghash_clmulni_intel pcbc snd_seq_midi snd_seq_midi_event snd_rawmidi input_leds snd_seq snd_seq_device aesni_intel aes_x86_64 crypto_simd glue_helper cryptd snd_timer snd soundcore shpchp wmi mac_hid sch_fq_codel parport_pc ppdev lp parport ip_tables x_tables autofs4 dm_mirror dm_region_hash dm_log hid_generic usbhid hid amdkfd amd_iommu_v2 amdgpu chash ttm drm_kms_helper syscopyarea sysfillrect sysimgblt fb_sys_fops drm i2c_piix4 igb dca i2c_algo_bit ptp pps_core ahci libahci video Mar 4 15:02:12 alu kernel: [61027.931585] CPU: 4 PID: 12416 Comm: kworker/4:0 Tainted: G W 4.15.0-10-generic #11-Ubuntu Mar 4 15:02:12 alu kernel: [61027.933074] Hardware name: System manufacturer System Product Name/ROG STRIX X370-F GAMING, BIOS 3803 01/22/2018 Mar 4 15:02:12 alu kernel: [61027.934681] Workqueue: events dm_irq_work_func [amdgpu] Mar 4 15:02:12 alu kernel: [61027.936321] RIP: 0010:generic_reg_wait+0xe8/0x120 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.937931] RSP: 0018:ffffb10e8e45b908 EFLAGS: 00010297 Mar 4 15:02:12 alu kernel: [61027.939544] RAX: 0000000000000001 RBX: 0000000000000065 RCX: 0000000000000000 Mar 4 15:02:12 alu kernel: [61027.941191] RDX: 0000000000000000 RSI: ffffa09e5ed16458 RDI: ffffa09e5ed16458 Mar 4 15:02:12 alu kernel: [61027.942862] RBP: ffffb10e8e45b948 R08: 0000000000000000 R09: 0000000000000989 Mar 4 15:02:12 alu kernel: [61027.944565] R10: 0000000000000002 R11: 00000000ffffffff R12: 0000000000000001 Mar 4 15:02:12 alu kernel: [61027.946263] R13: ffffa09e50003980 R14: 0000000000000100 R15: 0000000000000001 Mar 4 15:02:12 alu kernel: [61027.948014] FS: 0000000000000000(0000) GS:ffffa09e5ed00000(0000) knlGS:0000000000000000 Mar 4 15:02:12 alu kernel: [61027.949809] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 Mar 4 15:02:12 alu kernel: [61027.951608] CR2: 00007fd504b6dcf0 CR3: 000000081546c000 CR4: 00000000003406e0 Mar 4 15:02:12 alu kernel: [61027.953442] Call Trace: Mar 4 15:02:12 alu kernel: [61027.955353] tgn10_lock+0xa2/0xb0 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.957271] program_all_pipe_in_tree+0x804/0x8b0 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.959129] ? free_one_page+0x76/0x400 Mar 4 15:02:12 alu kernel: [61027.961038] ? amdgpu_cgs_read_register+0x14/0x20 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.962985] dcn10_apply_ctx_for_surface+0x498/0x4f0 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.964927] dc_commit_state+0x2aa/0x500 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.966893] amdgpu_dm_atomic_commit_tail+0x2cd/0xa50 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.968823] ? amdgpu_bo_pin_restricted+0x1b5/0x2a0 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.970671] ? _cond_resched+0x19/0x40 Mar 4 15:02:12 alu kernel: [61027.972534] ? wait_for_completion_interruptible+0x35/0x180 Mar 4 15:02:12 alu kernel: [61027.974425] commit_tail+0x42/0x70 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.976344] drm_atomic_helper_commit+0x10c/0x120 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.978341] amdgpu_dm_atomic_commit+0x87/0xa0 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.980323] drm_atomic_commit+0x51/0x60 [drm] Mar 4 15:02:12 alu kernel: [61027.982317] restore_fbdev_mode_atomic+0x178/0x1e0 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.984343] restore_fbdev_mode+0x32/0x140 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.986370] ? _cond_resched+0x19/0x40 Mar 4 15:02:12 alu kernel: [61027.988417] drm_fb_helper_restore_fbdev_mode_unlocked.part.32+0x28/0x80 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.990509] drm_fb_helper_set_par+0x43/0x70 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.992620] drm_fb_helper_hotplug_event.part.31+0xa8/0xb0 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.994766] drm_fb_helper_hotplug_event+0x1a/0x20 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61027.996953] amdgpu_fb_output_poll_changed+0x1a/0x20 [amdgpu] Mar 4 15:02:12 alu kernel: [61027.999185] amdgpu_output_poll_changed+0x12/0x20 [amdgpu] Mar 4 15:02:12 alu kernel: [61028.001392] drm_kms_helper_hotplug_event+0x2a/0x30 [drm_kms_helper] Mar 4 15:02:12 alu kernel: [61028.003662] handle_hpd_irq+0x8c/0xa0 [amdgpu] Mar 4 15:02:12 alu kernel: [61028.005952] dm_irq_work_func+0x5d/0x70 [amdgpu] Mar 4 15:02:12 alu kernel: [61028.008207] process_one_work+0x1ef/0x410 Mar 4 15:02:12 alu kernel: [61028.010474] worker_thread+0x32/0x410 Mar 4 15:02:12 alu kernel: [61028.012759] kthread+0x121/0x140 Mar 4 15:02:12 alu kernel: [61028.015040] ? process_one_work+0x410/0x410 Mar 4 15:02:12 alu kernel: [61028.017366] ? kthread_create_worker_on_cpu+0x70/0x70 Mar 4 15:02:12 alu kernel: [61028.019716] ? do_syscall_64+0x76/0x130 Mar 4 15:02:12 alu kernel: [61028.022056] ? SyS_exit_group+0x14/0x20 Mar 4 15:02:12 alu kernel: [61028.024423] ret_from_fork+0x22/0x40 Mar 4 15:02:12 alu kernel: [61028.026804] Code: 31 f6 44 8b 45 10 44 89 e1 48 c7 c7 a3 56 55 c0 89 45 d4 52 48 c7 c2 10 dd 54 c0 e8 f3 7e d8 ff 41 83 7d 20 01 58 8b 45 d4 74 02 <0f> ff 48 8d 65 d8 5b 41 5c 41 5d 41 5e 41 5f 5d c3 c7 45 c4 23 Mar 4 15:02:12 alu kernel: [61028.029348] ---[ end trace 01e28a103b34dd40 ]--- Mar 4 15:02:12 alu kernel: [61028.031938] [drm] DC: Cursor address is 0! Mar 4 15:02:12 alu kernel: [61028.037413] [drm] DC: Cursor address is 0! Mar 4 15:02:12 alu kernel: [61028.040391] [drm] {1920x1080, 2200x1125@148500Khz} Mar 4 15:02:12 alu kernel: [61028.044585] [drm] DC: Cursor address is 0! Mar 4 15:02:12 alu kernel: [61028.049994] [drm] DC: Cursor address is 0! blacklab%