Linux hangs after reboot

[nxp-user-liliangbao]

Hello everyone!

I have problem with linux kernel 4.19.35 on my IMX6ULL.

When I enter "reboot" command with the terminal, kernel maybe hang.

The probability is very low, and the log is below.

Any one know same hint, please help me, thanks vey much.

1. The reboot log with problem:

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root@npi:/opt/scripts/boot# reboot
root@npi:/opt/scripts/boot# [ OK ] Stopped target Timers.
[ OK ] Stopped Daily Cleanup of Temporary Directories.
[ OK ] Stopped target Graphical Interface.
[ OK ] Stopped target Multi-User System.
Stopping Generic Board Startup...
Stopping LSB: Start busybox udhcpd at boot time...
Stopping ebf-qtdemo qtdemo...
Stopping Avahi mDNS/DNS-SD Stack...
Stopping System Logging Service...
Stopping Regular background program processing daemon...
Stopping OpenBSD Secure Shell server...
[ OK ] Stopped target Login Prompts.
[ 476.233933] console [ttyGS-1] disabled
[ 476.241825] Unable to handle kernel paging request at virtual address 2f406500
[ 476.249081] pgd = 2f7ce882
[ 476.251795] [2f406500] *pgd=00000000
[ 476.255388] Internal error: Oops: 5 [#1] PREEMPT SMP ARM
[ 476.260705] Modules linked in: g_multi(-) snd_soc_imx_wm8960 inv_mpu6050_i2c snd_soc_wm8960 inv_mpu6050 goodix snd_soc_fsl_sai imx_pcm_dma_v2 snd_soc_fsl_asrc snd_soc_core snd_pcm_dmaengine snd_pcm snd_timer
[ 476.279191] CPU: 0 PID: 435 Comm: (agetty) Not tainted 4.19.35-imx6 #1.2212stable
[ 476.286677] Hardware name: Freescale i.MX6 UltraLite (Device Tree)
[ 476.292875] PC is at __cancel_work_timer+0x60/0x1ec
[ 476.297761] LR is at try_to_grab_pending+0x2c/0x14c
[ 476.302644] pc : [<80148704>] lr : [<801484f8>] psr: 20010093
[ 476.308915] sp : 88711d80 ip : 00000000 fp : 810ae690
[ 476.314144] r10: 00000000 r9 : 8912297c r8 : 00000000
[ 476.319374] r7 : 00000000 r6 : 81406148 r5 : 88b5ce04 r4 : 88710000
[ 476.325906] r3 : 00000001 r2 : 2f406500 r1 : 88b5ce04 r0 : 00000000
[ 476.332439] Flags: nzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none
[ 476.339667] Control: 10c53c7d Table: 882cc06a DAC: 00000051
[ 476.345419] Process (agetty) (pid: 435, stack limit = 0xe157e955)
[ 476.351519] Stack: (0x88711d80 to 0x88712000)
[ 476.355889] 1d80: 60010013 80513c90 89122800 00000000 89122818 88a51480 891229a8 e73dd3a9
[ 476.364077] 1da0: 89122800 89122800 00000000 88a51480 891229a8 8050b830 8143e328 8050b920
[ 476.372264] 1dc0: 89122800 00000000 88413640 8050c7cc 8878d63c 00000000 0000017c 89122904
[ 476.380452] 1de0: 89122904 810f3fdc 88c42a00 88a51480 00000000 8913d030 8822fe10 8633c550
[ 476.388639] 1e00: 00000008 88a51488 0051debc 8023a16c 00000000 00000000 00000000 88c42e5c
[ 476.396827] 1e20: 88c42a00 8151abd0 88c42e78 88a51480 00000004 8014c11c 88c42a00 8878d600
[ 476.405014] 1e40: 88710000 00000474 88711e5c 00000000 00000004 80134048 00000004 88711e60
[ 476.413201] 1e60: 00000000 e73dd3a9 00000000 891e2f04 0051debc 801348d4 ffffe000 76e39744
[ 476.421390] 1e80: 400004d8 891e2f04 ffffe000 8013eb7c 88a51480 88711edc 891e2a00 88711ef0
[ 476.429578] 1ea0: 418004fc ffffe000 89122800 88711fb0 76e39744 81406148 88711edc 76e39746
[ 476.437765] 1ec0: fffffe00 00000004 0051debc 8010ba30 88711f78 00000000 76dab360 0000000a
[ 476.445953] 1ee0: 0051debc 80238fec 00000002 e73dd3a9 00000009 88a51480 81406148 7ec86360
[ 476.454143] 1f00: 88a51480 00000003 8913d030 8024ba9c 88413280 88a51488 00000000 81406148
[ 476.462330] 1f20: 00000003 882e0400 8871e0c0 00000000 00000000 e73dd3a9 882e0400 0000000a
[ 476.470520] 1f40: 88a51480 76dab360 88711f78 00000000 76dab360 802392a8 88a51480 8808f000
[ 476.478707] 1f60: 81406148 88a51480 00000000 00000000 88a51480 e73dd3a9 00000000 ffffe000
[ 476.486896] 1f80: 80101204 88711fb0 00000004 80101204 88710000 00000004 0051debc 8010c094
[ 476.495084] 1fa0: 00000074 76dab360 00000003 8010106c 00000003 76dab360 0000000a 00000000
[ 476.503271] 1fc0: 00000074 76dab360 00000003 00000004 00000000 00000000 0112dc8e 0051debc
[ 476.511458] 1fe0: 00000004 7ec863c0 76eb03b3 76e39744 200d0030 00000003 00000000 00000000
[ 476.519661] [<80148704>] (__cancel_work_timer) from [<8050b830>] (release_tty+0x88/0xf8)
[ 476.527768] [<8050b830>] (release_tty) from [<8050b920>] (tty_release_struct+0x34/0x40)
[ 476.535783] [<8050b920>] (tty_release_struct) from [<8050c7cc>] (tty_release+0x3a0/0x608)
[ 476.543973] [<8050c7cc>] (tty_release) from [<8023a16c>] (__fput+0x88/0x1c4)
[ 476.551037] [<8023a16c>] (__fput) from [<8014c11c>] (task_work_run+0x94/0xb4)
[ 476.558188] [<8014c11c>] (task_work_run) from [<80134048>] (do_exit+0x2b4/0xad8)
[ 476.565599] [<80134048>] (do_exit) from [<801348d4>] (do_group_exit+0x3c/0xbc)
[ 476.572836] [<801348d4>] (do_group_exit) from [<8013eb7c>] (get_signal+0xfc/0x770)
[ 476.580421] [<8013eb7c>] (get_signal) from [<8010ba30>] (do_signal+0x74/0x4fc)
[ 476.587655] [<8010ba30>] (do_signal) from [<8010c094>] (do_work_pending+0xcc/0xe4)
[ 476.595236] [<8010c094>] (do_work_pending) from [<8010106c>] (slow_work_pending+0xc/0x20)
[ 476.603417] Exception stack(0x88711fb0 to 0x88711ff8)
[ 476.608476] 1fa0: 00000003 76dab360 0000000a 00000000
[ 476.616665] 1fc0: 00000074 76dab360 00000003 00000004 00000000 00000000 0112dc8e 0051debc
[ 476.624852] 1fe0: 00000004 7ec863c0 76eb03b3 76e39744 200d0030 00000003
[ 476.631479] Code: e5952000 e3120004 13c220ff 01a042a2 (15923000)
[ 476.637582] ---[ end trace 55d28a7eade12812 ]---
[ 476.642207] Fixing recursive fault but reboot is needed!

root@npi:/opt/scripts/boot#

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2. The normal reboot log:

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[ OK ] Stopped target Timers.
[ OK ] Stopped Daily Cleanup of Temporary Directories.
[ OK ] Stopped Daily rotation of log files.
[ OK ] Stopped target System Time Synchronized.
[ OK ] Removed slice system-systemd\x2dbacklight.slice.
Stopping Login Service...
Stopping Regular background program processing daemon...
[ OK ] Stopped target Login Prompts.
Stopping Serial Getty on ttymxc0...
Stopping Getty on ttyGS0...
Stopping Avahi mDNS/DNS-SD Stack...
Stopping System Logging Service...
Stopping ebf-qtdemo qtdemo...
Stopping LSB: Start busybox udhcpd at boot time...
Stopping rng-tools.service...
Stopping start_app daemon...
[ OK ] Stopped Login Service.
[ OK ] Stopped Regular background program processing daemon.
[ OK ] Stopped Avahi mDNS/DNS-SD Stack.
[ OK ] Stopped Generic Board Startup.
[ OK ] Stopped System Logging Service.
[ OK ] Stopped start_app daemon.
[ OK ] Stopped ebf-qtdemo qtdemo.
[ OK ] Stopped Getty on ttyGS0.
[ OK ] Stopped Serial Getty on ttymxc0.
[ OK ] Stopped OpenBSD Secure Shell server.
[ OK ] Stopped rng-tools.service.
[ OK ] Removed slice system-serial\x2dgetty.slice.
[ OK ] Removed slice system-getty.slice.
Stopping Permit User Sessions...
[ OK ] Stopped LSB: Start busybox udhcpd at boot time.
[ OK ] Stopped Permit User Sessions.
[ 28.331984] fec 20b4000.ethernet eth2: Link is Up - 100Mbps/Full - flow control rx/tx
[ OK ] Stopped target Remote File Systems.
[ 28.346175] IPv6: ADDRCONF(NETDEV_CHANGE): eth2: link becomes ready
[ OK ] Stopped target Network.
Stopping Connection service...
Stopping Raise network interfaces...
[ OK ] Stopped Raise network interfaces.
[ OK ] Stopped Connection service.
Stopping D-Bus System Message Bus...
[ OK ] Stopped D-Bus System Message Bus.
[ OK ] Stopped target Basic System.
[ OK ] Stopped target Slices.
[ OK ] Removed slice User and Session Slice.
[ OK ] Stopped target Sockets.
[ OK ] Closed Syslog Socket.
[ OK ] Closed Avahi mDNS/DNS-SD Stack Activation Socket.
[ OK ] Stopped target Paths.
[ OK ] Closed D-Bus System Message Bus Socket.
[ OK ] Stopped target System Initialization.
[ OK ] Stopped Apply Kernel Variables.
[ OK ] Stopped target Local Encrypted Volumes.
[ OK ] Stopped Forward Password R…uests to Wall Directory Watch.
[ OK ] Stopped Dispatch Password …ts to Console Directory Watch.
[ OK ] Stopped Load Kernel Modules.
Stopping Network Time Synchronization...
[ OK ] Stopped Network Time Synchronization.
[ OK ] Stopped Create Volatile Files and Directories.
[ OK ] Stopped target Local File Systems.
Unmounting /mnt/.psplash...
[ OK ] Unmounted /mnt/.psplash.
[ OK ] Reached target Unmount All Filesystems.
[ OK ] Stopped target Local File Systems (Pre).
[ OK ] Stopped Create Static Device Nodes in /dev.
[ OK ] Stopped Create System Users.
[ OK ] Stopped Remount Root and Kernel File Systems.
[ OK ] Stopped target Swap.
[ OK ] Reached target Shutdown.
[ OK ] Reached target Final Step.
[ OK ] Started Reboot.
[ OK ] Reached target Reboot.
[ 29.999074] watchdog: watchdog0: watchdog did not stop!
[ 30.011309] systemd-shutdow: 39 output lines suppressed due to ratelimiting
[ 30.558772] systemd-shutdown[1]: Syncing filesystems and block devices.
[ 30.577808] systemd-shutdown[1]: Sending SIGTERM to remaining processes...
[ 30.597610] systemd-journald[176]: Received SIGTERM from PID 1 (systemd-shutdow).
[ 30.642782] systemd-shutdown[1]: Sending SIGKILL to remaining processes...
[ 30.664950] systemd-shutdown[1]: Hardware watchdog 'imx2+ watchdog', version 0
[ 30.677237] systemd-shutdown[1]: Unmounting file systems.
[ 30.690922] [457]: Remounting '/' read-only in with options 'assert=read-only,ubi=0,vol=0'.
[ 30.706947] UBIFS (ubi0:0): background thread "ubifs_bgt0_0" stops
[ 30.722742] systemd-shutdown[1]: All filesystems unmounted.
[ 30.729246] systemd-shutdown[1]: Deactivating swaps.
[ 30.734585] systemd-shutdown[1]: All swaps deactivated.
[ 30.744423] systemd-shutdown[1]: Detaching loop devices.
[ 30.759018] systemd-shutdown[1]: All loop devices detached.
[ 30.780069] ci_hdrc ci_hdrc.1: remove, state 4
[ 30.784570] usb usb1: USB disconnect, device number 1
[ 30.791231] ci_hdrc ci_hdrc.1: USB bus 1 deregistered
[ 30.801307] imx2-wdt 20bc000.wdog: Device shutdown: Expect reboot!
[ 30.807628] reboot: Restarting system

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