Hello,

This happens in mainline kernel v4.15-rc1 on LENOVO IdeaPad U410. It at least dates back to v4.11 .

It occurs in 72 out of 72 boots.

[ 78.631475] [ 78.633086] ------------[ cut here ]------------ [ 78.633343] Could not determine valid watermarks for inherited state [ 78.633388] Selecting previously unselected package mime-support. [ 78.633390] [ 78.634210] WARNING: CPU: 1 PID: 185 at drivers/gpu/drm/i915/intel_display.c:14422 intel_modeset_init+0x3dc/0xf60 [i915] [ 78.634878] Modules linked in: intel_rapl x86_pkg_temp_thermal intel_powerclamp coretemp kvm_intel kvm irqbypass crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel pcbc wmi_bmof aesni_intel crypto_simd glue_helper cryptd ahci serio_raw snd_hda_intel snd_hda_codec pcspkr libahci libata snd_hda_core snd_hwdep snd_pcm snd_timer snd bcma soundcore i915(+) drm_kms_helper uvcvideo syscopyarea videobuf2_vmalloc sysfillrect videobuf2_memops sysimgblt fb_sys_fops videobuf2_v4l2 videobuf2_core ideapad_laptop drm videodev sparse_keymap shpchp wmi rfkill video ip_tables [ 78.635007] (Reading database ... 2202 files and directories currently installed.) [ 78.635008] [ 78.636245] Preparing to unpack .../deb/mime-support_3.60_all.deb ... [ 78.636247] [ 78.637067] Unpacking mime-support (3.60) ... [ 78.637069] [ 78.638780] Preparing to unpack .../opt/deb/debconf_1.5.63_all.deb ... [ 78.638783] [ 78.639367] CPU: 1 PID: 185 Comm: systemd-udevd Not tainted 4.15.0-rc1 #1 [ 78.639741] Hardware name: LENOVO IdeaPad U410 /Lenovo , BIOS 65CN15WW 06/05/2012 [ 78.640236] task: ffff88011c894c80 task.stack: ffffc90000a9c000 [ 78.640630] RIP: 0010:intel_modeset_init+0x3dc/0xf60 [i915] [ 78.640940] RSP: 0018:ffffc90000a9fb10 EFLAGS: 00010286 [ 78.641236] RAX: 0000000000000038 RBX: ffff880116c60000 RCX: 0000000000000000 [ 78.641529] Unpacking debconf (1.5.63) over (1.5.59) ... [ 78.641531] [ 78.642041] RDX: ffff88011f2561c0 RSI: ffff88011f24e018 RDI: ffff88011f24e018 [ 78.642480] RBP: ffff880119885400 R08: 000000000000036b R09: 0000000000000000 [ 78.642895] R10: 0000000000000000 R11: ffffffff827030ad R12: 00000000ffffffea [ 78.643289] R13: ffff88011c771800 R14: 0000000000000000 R15: ffff88011c76ce00 [ 78.643709] FS: 00007f41700eb8c0(0000) GS:ffff88011f240000(0000) knlGS:0000000000000000 [ 78.644154] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 78.644471] CR2: 00007f5b179c8750 CR3: 000000011c7b0006 CR4: 00000000001606e0 [ 78.644863] Call Trace: [ 78.645060] i915_driver_load+0xa4c/0xe20 [i915] [ 78.645369] local_pci_probe+0x3d/0x90: local_pci_probe at drivers/pci/pci-driver.c:307 [ 78.645610] ? _cond_resched+0x19/0x30: _cond_resched at kernel/sched/core.c:4855 [ 78.645826] pci_device_probe+0x11d/0x180: pci_call_probe at drivers/pci/pci-driver.c:361 (inlined by) __pci_device_probe at drivers/pci/pci-driver.c:386 (inlined by) pci_device_probe at drivers/pci/pci-driver.c:426 [ 78.646056] driver_probe_device+0x30c/0x480: really_probe at drivers/base/dd.c:425 (inlined by) driver_probe_device at drivers/base/dd.c:566 [ 78.646334] __driver_attach+0x9d/0xe0: __driver_attach at drivers/base/dd.c:800 [ 78.646547] ? driver_probe_device+0x480/0x480: __driver_attach at drivers/base/dd.c:770 [ 78.646819] bus_for_each_dev+0x5c/0x90: bus_for_each_dev at drivers/base/bus.c:313 [ 78.647048] bus_add_driver+0x1c2/0x260: bus_add_driver at drivers/base/bus.c:670 [ 78.647264] ? 0xffffffffa034c000 [ 78.647454] driver_register+0x57/0xc0: driver_register at drivers/base/driver.c:169 [ 78.647666] ? 0xffffffffa034c000 [ 78.647856] do_one_initcall+0x3b/0x160: do_one_initcall at init/main.c:826 [ 78.648076] ? _cond_resched+0x19/0x30: _cond_resched at kernel/sched/core.c:4855 [ 78.648290] ? kmem_cache_alloc_trace+0x170/0x1c0: slab_pre_alloc_hook at mm/slab.h:419 (inlined by) slab_alloc_node at mm/slub.c:2651 (inlined by) slab_alloc at mm/slub.c:2733 (inlined by) kmem_cache_alloc_trace at mm/slub.c:2750 [ 78.648554] ? do_init_module+0x22/0x1f8: do_init_module at kernel/module.c:3432 [ 78.648775] do_init_module+0x5b/0x1f8: do_init_module at kernel/module.c:3448 [ 78.648989] load_module+0x162a/0x1ac0: load_module at kernel/module.c:3771 [ 78.649204] ? SYSC_finit_module+0xb7/0xd0: SYSC_finit_module at kernel/module.c:3870 [ 78.649434] SYSC_finit_module+0xb7/0xd0: SYSC_finit_module at kernel/module.c:3870 [ 78.649660] entry_SYSCALL_64_fastpath+0x1a/0x7d: entry_SYSCALL_64_fastpath at arch/x86/entry/entry_64.S:210 [ 78.649920] RIP: 0033:0x7f416ef66d49 [ 78.650121] RSP: 002b:00007fff4f50ec78 EFLAGS: 00000246 ORIG_RAX: 0000000000000139 [ 78.650540] RAX: ffffffffffffffda RBX: 0000000000000014 RCX: 00007f416ef66d49 [ 78.650932] RDX: 0000000000000000 RSI: 00007f416f882525 RDI: 0000000000000014 [ 78.651326] RBP: 00007fff4f50dc70 R08: 0000000000000000 R09: 00007fff4f50f1f0 [ 78.651720] R10: 0000000000000014 R11: 0000000000000246 R12: 0000000000000005 [ 78.652113] R13: 0000555590d88760 R14: 00007fff4f50dc50 R15: 0000000000000005 [ 78.652503] Code: 49 c7 c0 90 c4 29 a0 0f 87 42 05 00 00 41 b9 04 00 00 00 49 c7 c0 b0 c4 29 a0 e9 30 05 00 00 48 c7 c7 70 f6 2b a0 e8 14 41 e3 e0 <0f> ff f0 ff 4d 00 0f 88 bc 54 04 00 75 08 48 89 ef e8 8e 12 e4 [ 78.653548] ---[ end trace cc7de05c8a63596d ]--- [ 78.657991] [drm] Initialized i915 1.6.0 20171023 for 0000:00:02.0 on minor 0

Attached the full dmesg, kconfig and reproduce scripts.

Thanks, Fengguang