https://bugs.freedesktop.org/show_bug.cgi?id=100258

Bug ID: 100258 Summary: [BAT][SKL] Serial console hung in kms_flip when running IGT Product: DRI Version: DRI git Hardware: Other OS: All Status: NEW Severity: normal Priority: medium Component: IGT Assignee: dri-devel@lists.freedesktop.org Reporter: tomi.p.sarvela@intel.com

Testhost is i7-6700K on Gigabyte Z170 MB. Serial is real COM1 header. Lockup happened while running IGT testlist in loop (started from serial console, if that matters).

Kernel is built from DRM-Tip today. BIOS newest. Kconfig at https://intel-gfx-ci.01.org/CI/CI_DRM_2352/kernel.config.bz2

[22018.856538] [drm:intel_atomic_commit_tail [i915]] [CRTC:46:pipe C] [22018.856551] [drm:intel_power_well_disable [i915]] disabling DC off [22018.856566] [drm:skl_enable_dc6 [i915]] Enabling DC6 [22018.856577] [drm:gen9_set_dc_state [i915]] Setting DC state from 00 to 02 [22018.856997] [drm:intel_power_well_disable [i915]] disabling always-on [22018.857038] [drm:intel_runtime_suspend [i915]] Suspending device [22018.857680] [IGT] kms_flip: exiting, ret=0 [22018.859602] [drm:intel_runtime_suspend [i915]] Device suspended [22018.884658] [drm:intel_runtime_resume [i915]] Resuming device [22018.888911] [drm:intel_runtime_resume [i915]] Device resumed [22018.888993] [drm:intel_runtime_suspend [i915]] Suspending device [22018.891615] [drm:intel_runtime_suspend [i915]] Device suspended [22055.545628] INFO: task kms_flip:25920 blocked for more than 30 seconds. [22055.545629] Tainted: G U W 4.11.0-rc2-CI-CI_DRM_2357+ #1 [22055.545629] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. [22055.545630] kms_flip D 0 25920 20731 0x00000000 [22055.545631] Call Trace: [22055.545635] __schedule+0x3fd/0xbc0 [22055.545636] ? __mutex_unlock_slowpath+0x3e/0x2e0 [22055.545637] schedule+0x3b/0x90 [22055.545639] schedule_timeout+0x23b/0x490 [22055.545641] ? __save_stack_trace+0x7e/0xd0 [22055.545643] __down+0x80/0xc0 [22055.545644] ? _raw_spin_lock_irqsave+0x49/0x60 [22055.545645] down+0x3c/0x50 [22055.545647] console_lock+0x27/0x70 [22055.545648] ? capable+0x17/0x20 [22055.545650] vt_ioctl+0x51a/0x1440 [22055.545651] ? _raw_spin_unlock_irqrestore+0x3d/0x60 [22055.545652] ? __slab_free+0x39f/0x4f0 [22055.545654] tty_ioctl+0x384/0xe80 [22055.545655] ? _raw_spin_unlock_irqrestore+0x3d/0x60 [22055.545656] ? debug_check_no_obj_freed+0x117/0x220 [22055.545658] do_vfs_ioctl+0x90/0x6e0 [22055.545659] ? putname+0x4f/0x60 [22055.545661] SyS_ioctl+0x3c/0x70 [22055.545662] entry_SYSCALL_64_fastpath+0x1c/0xb1 [22055.545663] RIP: 0033:0x7f6c17851357 [22055.545663] RSP: 002b:00007fffa5d50198 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [22055.545664] RAX: ffffffffffffffda RBX: 0000000001566ea0 RCX: 00007f6c17851357 [22055.545664] RDX: 0000000000000000 RSI: 0000000000004b3a RDI: 0000000000000006 [22055.545665] RBP: 0000000000000000 R08: 00007fffa5d50160 R09: 0000000000000000 [22055.545665] R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000000 [22055.545665] R13: 00007fffa5d50ed0 R14: 0000000000000000 R15: 0000000000000000 [22055.545667] INFO: lockdep is turned off. [22055.545667] NMI backtrace for cpu 5 [22055.545669] CPU: 5 PID: 66 Comm: khungtaskd Tainted: G U W 4.11.0-rc2-CI-CI_DRM_2357+ #1 [22055.545669] Hardware name: Gigabyte Technology Co., Ltd. Z170X-UD5/Z170X-UD5-CF, BIOS F21 01/06/2 017 [22055.545669] Call Trace: [22055.545671] dump_stack+0x67/0x92 [22055.545672] ? irq_force_complete_move+0xf0/0xf0 [22055.545673] nmi_cpu_backtrace+0x92/0xa0 [22055.545674] ? irq_force_complete_move+0xf0/0xf0 [22055.545675] nmi_trigger_cpumask_backtrace+0xc0/0x100 [22055.545677] arch_trigger_cpumask_backtrace+0x14/0x20 [22055.545678] watchdog+0x433/0x600 [22055.545678] ? watchdog+0x9c/0x600 [22055.545680] kthread+0x107/0x140 [22055.545680] ? reset_hung_task_detector+0x10/0x10 [22055.545681] ? kthread_create_on_node+0x40/0x40 [22055.545682] ret_from_fork+0x2e/0x40 [22055.545684] Sending NMI from CPU 5 to CPUs 0-4,6-7: [22055.545690] NMI backtrace for cpu 0 skipped: idling at pc 0xffffffff818760f0 [22055.545691] NMI backtrace for cpu 1 skipped: idling at pc 0xffffffff818760f0 [22055.545721] NMI backtrace for cpu 7 skipped: idling at pc 0xffffffff818760f0 [22055.545722] NMI backtrace for cpu 3 skipped: idling at pc 0xffffffff818760f0 [22055.545723] NMI backtrace for cpu 2 skipped: idling at pc 0xffffffff818760f0 [22055.545723] NMI backtrace for cpu 6 skipped: idling at pc 0xffffffff818760f0 [22055.546688] NMI backtrace for cpu 4 [22055.546688] CPU: 4 PID: 25851 Comm: kworker/4:1 Tainted: G U W 4.11.0-rc2-CI-CI_DRM_23 57+ #1 [22055.546689] Hardware name: Gigabyte Technology Co., Ltd. Z170X-UD5/Z170X-UD5-CF, BIOS F21 01/06/2 017 [22055.546689] Workqueue: usb_hub_wq hub_event [22055.546689] task: ffff88041d3c0040 task.stack: ffffc900042b4000 [22055.546689] RIP: 0010:io_serial_in+0x13/0x20 [22055.546690] RSP: 0018:ffffc900042b79a0 EFLAGS: 00000002 [22055.546690] RAX: 0000000080000000 RBX: ffffffff83680100 RCX: 0000000000000000 [22055.546690] RDX: 00000000000003fd RSI: 0000000000000005 RDI: ffffffff83680100 [22055.546691] RBP: ffffc900042b79a0 R08: 0000000000000001 R09: 0000000000000001 [22055.546691] R10: 0000000000000000 R11: ffff88041d3c0040 R12: 0000000000002704 [22055.546691] R13: 0000000000000020 R14: ffffffff82d04fbb R15: ffffffff83680100 [22055.546691] FS: 0000000000000000(0000) GS:ffff88043ed00000(0000) knlGS:0000000000000000 [22055.546691] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [22055.546692] CR2: 00007f6c142323c0 CR3: 0000000003e0f000 CR4: 00000000003406e0 [22055.546692] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [22055.546692] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 [22055.546692] Call Trace: [22055.546693] wait_for_xmitr+0x37/0xa0 [22055.546693] serial8250_console_putchar+0x17/0x30 [22055.546693] ? wait_for_xmitr+0xa0/0xa0 [22055.546693] uart_console_write+0x2b/0x60 [22055.546693] serial8250_console_write+0xbc/0x270 [22055.546693] ? vt_console_print+0x22d/0x3b0 [22055.546694] univ8250_console_write+0x1c/0x20 [22055.546694] console_unlock+0x40e/0x530 [22055.546694] ? vprintk_emit+0x27a/0x380 [22055.546694] vprintk_emit+0x283/0x380 [22055.546694] ? snprintf+0x39/0x40 [22055.546695] dev_vprintk_emit+0xab/0x220 [22055.546695] ? usb_cache_string+0x7e/0xa0 [22055.546695] ? trace_hardirqs_on+0xd/0x10 [22055.546695] dev_printk_emit+0x39/0x40 [22055.546695] __dev_printk+0x37/0x80 [22055.546696] _dev_info+0x57/0x60 [22055.546696] usb_new_device+0x122/0x4a0 [22055.546696] hub_event+0xb18/0x1500 [22055.546696] process_one_work+0x1f4/0x6d0 [22055.546696] ? process_one_work+0x16e/0x6d0 [22055.546696] worker_thread+0x49/0x4a0 [22055.546697] kthread+0x107/0x140 [22055.546697] ? process_one_work+0x6d0/0x6d0 [22055.546697] ? kthread_create_on_node+0x40/0x40 [22055.546697] ret_from_fork+0x2e/0x40 [22055.546697] Code: 48 89 e5 d3 e6 48 63 f6 48 03 77 40 8b 06 5d c3 0f 1f 84 00 00 00 00 00 0f b6 8 f d1 00 00 00 8b 57 38 55 48 89 e5 d3 e6 01 f2 ec <0f> b6 c0 5d c3 0f 1f 84 00 00 00 00 00 0f b6 8f d1 00 00 00 89 [22055.546706] Kernel panic - not syncing: hung_task: blocked tasks [22055.546707] CPU: 5 PID: 66 Comm: khungtaskd Tainted: G U W 4.11.0-rc2-CI-CI_DRM_2357+ #1 [22055.546707] Hardware name: Gigabyte Technology Co., Ltd. Z170X-UD5/Z170X-UD5-CF, BIOS F21 01/06/2 017 [22055.546707] Call Trace: [22055.546708] dump_stack+0x67/0x92 [22055.546709] panic+0xcf/0x205 [22055.546711] ? irq_force_complete_move+0xf0/0xf0 [22055.546712] watchdog+0x43f/0x600 [22055.546712] ? watchdog+0x9c/0x600 [22055.546713] kthread+0x107/0x140 [22055.546714] ? reset_hung_task_detector+0x10/0x10 [22055.546715] ? kthread_create_on_node+0x40/0x40 [22055.546716] ret_from_fork+0x2e/0x40 [22055.555570] Kernel Offset: disabled [22070.033123] ---[ end Kernel panic - not syncing: hung_task: blocked tasks