After resuming from a "systemctl suspend" on Arch Linux with kernel 3.18.6 on my Broadwell generation system (Thinkpad T450s) the graphics are garbled in Xorg (restarting Xorg does not help). The virtual terminals are still usable. With i915.mmio_debug=1 I get the following error in the ring buffer: [ 164.119010] PM: noirq resume of devices complete after 15.597 msecs [ 164.119054] ------------[ cut here ]------------ [ 164.119080] WARNING: CPU: 1 PID: 1473 at drivers/gpu/drm/i915/intel_uncore.c:528 hsw_unclaimed_reg_debug+0x7d/0xa0 [i915]() [ 164.119081] Unclaimed register detected before reading register 0x130040 [ 164.119104] Modules linked in: ctr ccm rfcomm mousedev bnep cpufreq_stats ecb uvcvideo videobuf2_vmalloc videobuf2_memops videobuf2_core v4l2_common videodev btusb media bluetooth crc16 sn d_hda_codec_realtek snd_hda_codec_generic snd_hda_codec_hdmi arc4 nls_iso8859_1 intel_rapl nls_cp437 x86_pkg_temp_thermal intel_powerclamp kvm_intel vfat fat iwlmvm kvm mac80211 iTCO_wdt crct 10dif_pclmul iTCO_vendor_support crc32_pclmul crc32c_intel ghash_clmulni_intel aesni_intel aes_x86_64 lrw iwlwifi gf128mul glue_helper ablk_helper cryptd psmouse serio_raw pcspkr rtsx_pci_ms cfg80211 memstick snd_hda_intel snd_hda_controller thinkpad_acpi snd_hda_codec nvram snd_hwdep led_class wmi thermal snd_pcm e1000e rfkill tpm_tis battery tpm ac evdev snd_timer mei_me mei sn d lpc_ich i2c_i801 mac_hid soundcore shpchp ptp [ 164.119118] pps_core processor sch_fq_codel vboxdrv(O) coretemp hwmon msr nfs lockd grace sunrpc fscache acpi_call(O) zfs(PO) zunicode(PO) zcommon(PO) znvpair(PO) zavl(PO) spl(O) sd_mod r tsx_pci_sdmmc mmc_core atkbd libps2 ahci libahci libata rtsx_pci ehci_pci xhci_pci scsi_mod xhci_hcd ehci_hcd usbcore usb_common i8042 serio i915 button intel_gtt i2c_algo_bit video drm_kms_helper drm i2c_core [ 164.119120] CPU: 1 PID: 1473 Comm: kworker/u16:8 Tainted: P O 3.18.6-1-ARCH #1 [ 164.119121] Hardware name: LENOVO 20BWS03F00/20BWS03F00, BIOS JBET41WW (1.06 ) 12/23/2014 [ 164.119125] Workqueue: events_unbound async_run_entry_fn [ 164.119127] 0000000000000000 00000000bf74f563 ffff8802c8de7b18 ffffffff8154fb74 [ 164.119128] 0000000000000000 ffff8802c8de7b70 ffff8802c8de7b58 ffffffff81072c41 [ 164.119130] 0000000200000000 ffff88034b690000 0000000000130040 0000000000000000 [ 164.119130] Call Trace: [ 164.119134] [<ffffffff8154fb74>] dump_stack+0x4e/0x71 [ 164.119137] [<ffffffff81072c41>] warn_slowpath_common+0x81/0xa0 [ 164.119139] [<ffffffff81072cb5>] warn_slowpath_fmt+0x55/0x70 [ 164.119154] [<ffffffffa00d4d8d>] hsw_unclaimed_reg_debug+0x7d/0xa0 [i915] [ 164.119164] [<ffffffffa00d7e26>] gen6_read32+0x56/0x150 [i915] [ 164.119176] [<ffffffffa00ed99c>] hsw_disable_pc8+0x3c/0x360 [i915] [ 164.119178] [<ffffffff81438bb4>] ? raw_pci_write+0x24/0x50 [ 164.119186] [<ffffffffa008c5cb>] intel_resume_prepare+0x5bb/0x5e0 [i915] [ 164.119193] [<ffffffffa008c753>] i915_drm_thaw_early+0x23/0x70 [i915] [ 164.119201] [<ffffffffa008c810>] ? i915_resume_early+0x50/0x50 [i915] [ 164.119208] [<ffffffffa008c807>] i915_resume_early+0x47/0x50 [i915] [ 164.119215] [<ffffffffa008c825>] i915_pm_resume_early+0x15/0x20 [i915] [ 164.119218] [<ffffffff813c6e3c>] dpm_run_callback+0x4c/0x150 [ 164.119220] [<ffffffff813c71eb>] device_resume_early+0xbb/0x1d0 [ 164.119222] [<ffffffff813c7321>] async_resume_early+0x21/0x50 [ 164.119224] [<ffffffff81093a9c>] async_run_entry_fn+0x4c/0x170 [ 164.119227] [<ffffffff8108b845>] process_one_work+0x145/0x400 [ 164.119229] [<ffffffff8108be0b>] worker_thread+0x6b/0x480 [ 164.119231] [<ffffffff8108bda0>] ? init_pwq.part.22+0x10/0x10 [ 164.119233] [<ffffffff81090e6a>] kthread+0xea/0x100 [ 164.119235] [<ffffffff81090d80>] ? kthread_create_on_node+0x1c0/0x1c0 [ 164.119237] [<ffffffff8155563c>] ret_from_fork+0x7c/0xb0 [ 164.119239] [<ffffffff81090d80>] ? kthread_create_on_node+0x1c0/0x1c0 [ 164.119240] ---[ end trace ce36562f157b91eb ]--- [ 164.137003] PM: early resume of devices complete after 17.956 msecs The full dmesg is attached. Let me know if you need any further information, as I can reliably reproduce this problem. Cheers, Tobias
Created attachment 169081 [details] dmesg log
Fixed in 4.0 (or earlier).