[Samsung Galaxy J7 Questions & Answers] JuhaniJ:
I have Samsung J7 (model SM-J730F) which has Android version 8.1.0. Sometimes it boots fine, but very often the phone gets stuck displaying time - that is, the phone does not show the normal user interface.

When I connect the phone to my PC, command "adb logcat *:E" displays repeatedly the following error:

01-07 11:29:20.369 4067 4067 E audit : type=1701 audit(1546853360.359:450): auid=4294967295 uid=10006 gid=10006 ses=4294967295 subj=u:r:platform_app:s0:c512,c768 pid=21158 comm="SysUiBg" exe="/system/bin/app_process32" sig=11
01-07 11:29:20.428 4391 5888 E SystemUIAdapter: binderDied() key = 80
01-07 11:29:20.428 4391 4507 E InputDispatcher: channel ~ Channel is unrecoverably broken and will be disposed!
01-07 11:29:20.428 4391 4507 E InputDispatcher: channel ~ Channel is unrecoverably broken and will be disposed!
01-07 11:29:20.458 21184 21184 E Zygote : isWhitelistProcess - Process is Whitelisted
01-07 11:29:20.614 21184 21184 E CoverUI : onCreate() - mStatusBar is null
01-07 11:29:20.616 21184 21196 E CoverUI : onCreate() - mStatusBar is null
01-07 11:29:20.616 21184 21196 E CoverUI : updateCoverState() - cannot find mStatusBar
01-07 11:29:20.616 21184 21196 E CoverUI : onCreate() - mStatusBar is null
01-07 11:29:20.616 21184 21196 E CoverUI : updateCoverState() - cannot find mStatusBar
01-07 11:29:20.693 4391 4391 E KioskModeService: There's no matched data
01-07 11:29:20.695 5299 5299 E KNOXCORE::CACHE: clr value {old=1 new:1
01-07 11:29:20.707 21184 21184 E SoundPool: error loading /system/media/audio/ui/Trusted.ogg
01-07 11:29:20.707 5299 5299 E KNOXCORE::CACHE: clr value {old=0 new:0
01-07 11:29:20.884 4391 5708 E CoverManager.StateNotifier: addListenerToListLocked : duplicated listener handle
01-07 11:29:21.383 21184 21184 E MultiSimMgrUtils: Package not found : com.samsung.android.globalroaming
01-07 11:29:21.497 21184 21223 F libc : Fatal signal 11 (SIGSEGV), code 1, fault addr 0x9 in tid 21223 (SysUiBg), pid 21184 (ndroid.systemui)
01-07 11:29:21.571 21248 21248 F DEBUG : *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
01-07 11:29:21.571 21248 21248 F DEBUG : Build fingerprint: 'samsung/j7y17ltexx/j7y17lte:8.1.0/M1AJQ/J730FXXU3BRJ1:user/release-keys'
01-07 11:29:21.571 21248 21248 F DEBUG : Revision: '7'
01-07 11:29:21.571 21248 21248 F DEBUG : ABI: 'arm'
01-07 11:29:21.571 21248 21248 F DEBUG : pid: 21184, tid: 21223, name: SysUiBg >>> com.android.systemui <<<
01-07 11:29:21.571 21248 21248 F DEBUG : signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0x9
01-07 11:29:21.571 21248 21248 F DEBUG : Cause: null pointer dereference
01-07 11:29:21.571 21248 21248 F DEBUG : r0 70c12070 r1 13ddf520 r2 00000001 r3 00000009
01-07 11:29:21.571 21248 21248 F DEBUG : r4 00000001 r5 00000001 r6 13ddf520 r7 13dcef70
01-07 11:29:21.571 21248 21248 F DEBUG : r8 00000000 r9 e52af000 sl 00000001 fp 144b8410
01-07 11:29:21.571 21248 21248 F DEBUG : ip 00000000 sp d247a520 lr d4d61449 pc 71675d5e cpsr 200e0030
01-07 11:29:21.672 21248 21248 F DEBUG :
01-07 11:29:21.672 21248 21248 F DEBUG : backtrace:
01-07 11:29:21.672 21248 21248 F DEBUG : #00 pc 00262d5e /system/framework/arm/boot.oat (offset 0x1cc000) (java.lang.StringBuilder.append+61)
01-07 11:29:21.672 21248 21248 F DEBUG : #01 pc 0021a447 /data/dalvik-cache/arm/system@priv-app@SystemUI@SystemUI.apk@classes.dex (offset 0x17a000)
01-07 11:29:21.736 4391 4545 E WifiNotificationController: clearPendingNotification with resetRepeatTime= true, state= 0
01-07 11:29:22.910 4125 4125 E /system/bin/tombstoned: Tombstone written to: /data/tombstones/tombstone_00

I have tried clearing the cache, but it does not solve the problem. I would like to fix this problem without factory reset. The phone is not rooted.