Hi, I have tried yet another RT kernel on my Acer laptop. This time it is 4.4.75 patched with the -rt88 patch. The system hung again when I started a few applications I would normally use with RT. This time I have not tried to reboot it immediately and the system came back to life after a couple of minutes. >From the kernel logs: Some time before the hung: Jul 30 19:01:54 lolek kernel: NOHZ: local_softirq_pending 80 The system locked up around 19:10 Next thing I got in the logs was: Jul 30 19:12:09 lolek kernel: INFO: task jbd2/dm-4-8:1407 blocked for more than 120 seconds. Jul 30 19:12:09 lolek kernel: Tainted: G W 4.4.75-rt88-1 #1 Jul 30 19:12:09 lolek kernel: "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. Jul 30 19:12:09 lolek kernel: jbd2/dm-4-8 D ffff880036a0bac0 0 1407 2 0x00000080 Jul 30 19:12:09 lolek kernel: ffff880036a0bac0 00ff88008fcb58a0 ffff880243ab0f80 ffff880243978000 Jul 30 19:12:09 lolek kernel: ffff880036a0c000 ffff880243978000 7fffffffffffffff ffffffff81658de0 Jul 30 19:12:09 lolek kernel: ffff880036a0bc28 ffff880036a0bae0 ffffffff8165838b 0000000000000000 Jul 30 19:12:09 lolek kernel: Call Trace: Jul 30 19:12:09 lolek kernel: [<ffffffff81658de0>] ? bit_wait+0x60/0x60 Jul 30 19:12:09 lolek kernel: [<ffffffff8165838b>] schedule+0x4b/0xe0 Jul 30 19:12:09 lolek kernel: [<ffffffff8165a660>] schedule_timeout+0x1e0/0x290 Jul 30 19:12:09 lolek kernel: [<ffffffff8135a4f7>] ? debug_smp_processor_id+0x17/0x20 Jul 30 19:12:09 lolek kernel: [<ffffffff81081387>] ? pin_current_cpu+0x87/0x1f0 Jul 30 19:12:09 lolek kernel: [<ffffffff81658de0>] ? bit_wait+0x60/0x60 Jul 30 19:12:09 lolek kernel: [<ffffffff81657934>] io_schedule_timeout+0xa4/0x110 Jul 30 19:12:09 lolek kernel: [<ffffffff8165b4f7>] ? rt_spin_unlock+0x27/0x40 Jul 30 19:12:09 lolek kernel: [<ffffffff81658dfb>] bit_wait_io+0x1b/0x70 Jul 30 19:12:09 lolek kernel: [<ffffffff816589db>] __wait_on_bit+0x5b/0x90 Jul 30 19:12:09 lolek kernel: [<ffffffff81658de0>] ? bit_wait+0x60/0x60 Jul 30 19:12:09 lolek kernel: [<ffffffff81658a92>] out_of_line_wait_on_bit+0x82/0xb0 Jul 30 19:12:09 lolek kernel: [<ffffffff810c7070>] ? autoremove_wake_function+0x40/0x40 Jul 30 19:12:09 lolek kernel: [<ffffffff812400f7>] __wait_on_buffer+0x27/0x30 Jul 30 19:12:09 lolek kernel: [<ffffffffc05ed54e>] jbd2_journal_commit_transaction+0x113e/0x1ad0 [jbd2] Jul 30 19:12:09 lolek kernel: [<ffffffff810efe8a>] ? try_to_del_timer_sync+0x5a/0x80 Jul 30 19:12:09 lolek kernel: [<ffffffff8135a4f7>] ? debug_smp_processor_id+0x17/0x20 Jul 30 19:12:09 lolek kernel: [<ffffffff81081506>] ? unpin_current_cpu+0x16/0x70 Jul 30 19:12:09 lolek kernel: [<ffffffffc05f37aa>] kjournald2+0xca/0x270 [jbd2] Jul 30 19:12:09 lolek kernel: [<ffffffff810c7030>] ? wake_atomic_t_function+0x60/0x60 Jul 30 19:12:09 lolek kernel: [<ffffffffc05f36e0>] ? commit_timeout+0x10/0x10 [jbd2] Jul 30 19:12:09 lolek kernel: [<ffffffff810a13d5>] kthread+0xe5/0x100 Jul 30 19:12:09 lolek kernel: [<ffffffff810a12f0>] ? kthread_worker_fn+0x170/0x170 Jul 30 19:12:09 lolek kernel: [<ffffffff8165bc8f>] ret_from_fork+0x3f/0x70 Jul 30 19:12:09 lolek kernel: [<ffffffff810a12f0>] ? kthread_worker_fn+0x170/0x170 and few other tasks hung in 'bit_wait' under jbd/ext4. Then problems from i915 drm driver were reported: Jul 30 19:12:22 lolek kernel: [drm:intel_pipe_update_end [i915]] *ERROR* Atomic update failure on pipe A (start=40468 end=40469) time 173 us, min 1073, max 1079, scanline start 1068, end 1081 [...] Jul 30 19:18:46 lolek kernel: [drm:intel_pipe_update_end [i915]] *ERROR* Atomic update failure on pipe A (start=63501 end=63502) time 249 us, min 1073, max 1079, scanline start 1065, end 1081 Jul 30 19:19:58 lolek kernel: [drm:intel_pipe_update_end [i915]] *ERROR* Atomic update failure on pipe A (start=67818 end=67819) time 100 us, min 1073, max 1079, scanline start 1072, end 1080 Jul 30 19:21:33 lolek kernel: [drm:intel_pipe_update_end [i915]] *ERROR* Atomic update failure on pipe A (start=73522 end=73523) time 127 us, min 1073, max 1079, scanline start 1071, end 1080 System seems to be working correctly after the lockup. Any ideas what is going on? Jacek -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
