Created attachment 122639 [details]
Example of binary file that caused the crash

SUMMARY
I called kdiff3 on 2 small NI I/O Trace files which I thought were text files but were indeed binary files. It locked up X11 for 10 minutes and eventually X11 restarted, closing all my open work.

Since I called it from the command line the following was shown (plus plenty of quotes and backslashes):
Geometry conversion of "-1,-1" to QSize failed
QMainWindow::addToolBar invalid area argument


STEPS TO REPRODUCE
1. call kdiff3 Capture1.nitrace Capture2.nitrace

OBSERVED RESULT
Entire desktop hangs for minutes then restarts

EXPECTED RESULT
kdiff3 says the files are different

SOFTWARE/OS VERSIONS
Operating System: Kubuntu 19.04
KDE Plasma Version: 5.15.4
KDE Frameworks Version: 5.56.0
Qt Version: 5.12.2
Kernel Version: 5.0.0-27-generic
OS Type: 64-bit
Processors: 8 × Intel® Core™ i7-4710MQ CPU @ 2.50GHz
Memory: 15.6 GiB of RAM

From syslog:
rtkit-daemon[2813]: The canary thread is apparently starving. Taking action.
rtkit-daemon[2813]: Demoting known real-time threads.
systemd[1]: systemd-logind.service: Watchdog timeout (limit 3min)!
rtkit-daemon[2813]: Successfully demoted thread 5855 of process 5831.
systemd[1]: systemd-logind.service: Killing process 1318 (systemd-logind) with signal SIGABRT.
rtkit-daemon[2813]: Successfully demoted thread 5854 of process 5831.
...
rtkit-daemon[2813]: Demoted 22 threads.
systemd[1]: Starting Process error reports when automatic reporting is enabled...
systemd[1]: systemd-logind.service: Main process exited, code=dumped, status=6/ABRT
systemd[1]: systemd-logind.service: Failed with result 'watchdog'.
systemd[1]: systemd-logind.service: Service has no hold-off time (RestartSec=0), scheduling restart.
systemd[1]: systemd-logind.service: Scheduled restart job, restart counter is at 1.
systemd[1]: Stopped Login Service.
kernel: [156421.612687] ksysguard invoked oom-killer: gfp_mask=0x6200ca(GFP_HIGHUSER_MOVABLE), order=0, oom_score_adj=0
kernel: [156421.612691] CPU: 5 PID: 3036 Comm: ksysguard Tainted: P           OE     5.0.0-27-generic #28-Ubuntu
kernel: [156421.612691] Hardware name: Hewlett-Packard HP ZBook 15 G2/2253, BIOS M70 Ver. 01.14 01/26/2016
kernel: [156421.612692] Call Trace:
kernel: [156421.612699]  dump_stack+0x63/0x8a
kernel: [156421.612702]  dump_header+0x54/0x308
kernel: [156421.612704]  oom_kill_process.cold.29+0xb/0x1d6
kernel: [156421.612706]  out_of_memory+0x1bc/0x480
kernel: [156421.612708]  __alloc_pages_slowpath+0xb68/0xea0
kernel: [156421.612711]  __alloc_pages_nodemask+0x2c4/0x2e0
kernel: [156421.612714]  alloc_pages_current+0x81/0xe0
kernel: [156421.612717]  __page_cache_alloc+0x6a/0xa0
kernel: [156421.612719]  filemap_fault+0x403/0x8a0
kernel: [156421.612722]  ? xas_load+0xc/0x80
kernel: [156421.612723]  ? xas_find+0x157/0x190
kernel: [156421.612725]  ? filemap_map_pages+0x1ae/0x380
kernel: [156421.612727]  ext4_filemap_fault+0x31/0x44
kernel: [156421.612730]  __do_fault+0x3c/0x130
kernel: [156421.612732]  __handle_mm_fault+0xe49/0x1280
kernel: [156421.612734]  handle_mm_fault+0xe1/0x210
kernel: [156421.612737]  __do_page_fault+0x23a/0x4c0
kernel: [156421.612738]  do_page_fault+0x2e/0xe0
kernel: [156421.612740]  ? page_fault+0x8/0x30
kernel: [156421.612742]  page_fault+0x1e/0x30
kernel: [156421.612744] RIP: 0033:0x7f9fcffe54a5
kernel: [156421.612748] Code: Bad RIP value.
kernel: [156421.612749] RSP: 002b:00007ffcbf8987f0 EFLAGS: 00010206
kernel: [156421.612750] RAX: 0000000000000001 RBX: 00005596a64a2228 RCX: 0000000000000000
kernel: [156421.612751] RDX: 00005596a600f020 RSI: 0000000000000002 RDI: 00005596a687f7a0
kernel: [156421.612752] RBP: 00007ffcbf898800 R08: 00005596a6f85e70 R09: 0000000000000006
kernel: [156421.612752] R10: 00005596a6f85e98 R11: 0000000000000000 R12: 00007ffcbf8987f8
kernel: [156421.612753] R13: 00007f9fcfc3c388 R14: 00005596a64a21e0 R15: 00007ffcbf898d40
kernel: [156421.612755] Mem-Info:
kernel: [156421.612759] active_anon:1975477 inactive_anon:258066 isolated_anon:0
kernel: [156421.612759]  active_file:962 inactive_file:1093 isolated_file:134
kernel: [156421.612759]  unevictable:66 dirty:46 writeback:75181 unstable:0
kernel: [156421.612759]  slab_reclaimable:124523 slab_unreclaimable:112382
kernel: [156421.612759]  mapped:1416865 shmem:24303 pagetables:23037 bounce:0
kernel: [156421.612759]  free:55740 free_pcp:2765 free_cma:0
kernel: [156421.612762] Node 0 active_anon:7901908kB inactive_anon:1032264kB active_file:3848kB inactive_file:4372kB unevictable:264kB isolated(anon):0kB isolated(file):536kB mapped:5667460kB dirty:184kB writeback:300724kB shmem:97212kB shmem_thp: 0kB shmem_pmdmapped: 0kB anon_thp: 0kB writeback_tmp:0kB unstable:0kB all_unreclaimable? no
kernel: [156421.612763] Node 0 DMA free:15884kB min:64kB low:80kB high:96kB active_anon:0kB inactive_anon:0kB active_file:0kB inactive_file:0kB unevictable:0kB writepending:0kB present:15984kB managed:15900kB mlocked:0kB kernel_stack:0kB pagetables:0kB bounce:0kB free_pcp:0kB local_pcp:0kB free_cma:0kB
kernel: [156421.612766] lowmem_reserve[]: 0 1331 15857 15857 15857
kernel: [156421.612768] Node 0 DMA32 free:63576kB min:5668kB low:7084kB high:8500kB active_anon:1337432kB inactive_anon:728kB active_file:28kB inactive_file:24kB unevictable:0kB writepending:60kB present:1502720kB managed:1437184kB mlocked:0kB kernel_stack:160kB pagetables:3936kB bounce:0kB free_pcp:256kB local_pcp:248kB free_cma:0kB
kernel: [156421.612772] lowmem_reserve[]: 0 0 14525 14525 14525
kernel: [156421.612773] Node 0 Normal free:143500kB min:154004kB low:169464kB high:184924kB active_anon:6564476kB inactive_anon:1031496kB active_file:4956kB inactive_file:5164kB unevictable:264kB writepending:300848kB present:15171584kB managed:14882848kB mlocked:264kB kernel_stack:23984kB pagetables:88212kB bounce:0kB free_pcp:10812kB local_pcp:1460kB free_cma:0kB
kernel: [156421.612776] lowmem_reserve[]: 0 0 0 0 0
kernel: [156421.612778] Node 0 DMA: 1*4kB (U) 1*8kB (U) 0*16kB 0*32kB 2*64kB (U) 1*128kB (U) 1*256kB (U) 0*512kB 1*1024kB (U) 1*2048kB (M) 3*4096kB (M) = 15884kB
kernel: [156421.612786] Node 0 DMA32: 122*4kB (UME) 604*8kB (UME) 265*16kB (UME) 292*32kB (UME) 192*64kB (UME) 89*128kB (UME) 62*256kB (UE) 4*512kB (UE) 1*1024kB (E) 1*2048kB (M) 0*4096kB = 63576kB
kernel: [156421.612793] Node 0 Normal: 6476*4kB (UME) 7431*8kB (UMEH) 1934*16kB (UMEH) 857*32kB (UMEH) 19*64kB (UMH) 2*128kB (H) 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 145192kB
kernel: [156421.612801] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=1048576kB
kernel: [156421.612802] Node 0 hugepages_total=0 hugepages_free=0 hugepages_surp=0 hugepages_size=2048kB
kernel: [156421.612803] 135417 total pagecache pages
kernel: [156421.612804] 108900 pages in swap cache
kernel: [156421.612806] Swap cache stats: add 4043688, delete 3979377, find 368232/710280
kernel: [156421.612806] Free swap  = 0kB
kernel: [156421.612807] Total swap = 8376316kB
kernel: [156421.612807] 4172572 pages RAM
kernel: [156421.612808] 0 pages HighMem/MovableOnly
kernel: [156421.612808] 88589 pages reserved
kernel: [156421.612809] 0 pages cma reserved
kernel: [156421.612809] 0 pages hwpoisoned
kernel: [156421.612810] Tasks state (memory values in pages):
kernel: [156421.612810] [  pid  ]   uid  tgid total_vm      rss pgtables_bytes swapents oom_score_adj name
kernel: [156421.613212] [  24428] 10705 24428  2623313  1916923 20725760   618647             0 kdiff3
...
kernel: [156421.613223] oom-kill:constraint=CONSTRAINT_NONE,nodemask=(null),cpuset=/,mems_allowed=0,global_oom,task_memcg=/user.slice/user-10705.slice/session-3.scope,task=kdiff3,pid=24428,uid=10705
kernel: [156421.613229] Out of memory: Kill process 24428 (kdiff3) score 411 or sacrifice child
kernel: [156421.613240] Killed process 24428 (kdiff3) total-vm:10493252kB, anon-rss:7667692kB, file-rss:0kB, shmem-rss:0kB
kernel: [156421.917905] oom_reaper: reaped process 24428 (kdiff3), now anon-rss:0kB, file-rss:0kB, shmem-rss:0kB
systemd[1]: Starting Login Service...
systemd[1]: Started Login Service.
sddm[1902]: Adding new display on vt 1 ...
sddm[1902]: Loading theme configuration from ""
sddm[1902]: Display server starting...
sddm[1902]: Running: /usr/bin/X -nolisten tcp -auth /var/run/sddm/{58ce7a82-44ae-4266-892d-31290e94e51f} -background none -noreset -displayfd 18 -seat seat0 vt1
sddm[1902]: Failed to read display number from pipe
sddm[1902]: Display server failed to start. Exiting
org.kde.kglobalaccel[2337]: The X11 connection broke (error 1). Did the X11 server die?
sddm[1902]: kwalletd5: Checking for pam module
sddm[1902]: kwalletd5: Got pam-login param
sddm[1902]: kwalletd5: Waiting for hash on 7-
sddm[1902]: kwalletd5: waitingForEnvironment on: 3
sddm[1902]: kwalletd5: client connected
sddm[1902]: kwalletd5: client disconnected
acpid: client 1992[0:0] has disconnected
org.kde.ActivityManager[2337]: The X11 connection broke (error 1). Did the X11 server die?
systemd[1]: sddm.service: Main process exited, code=dumped, status=6/ABRT
pulseaudio[2796]: ICE default IO error handler doing an exit(), pid = 2796, errno = 11
org.kde.KScreen[2337]: The X11 connection broke (error 1). Did the X11 server die?
acpid: client connected from 1992[0:0]
org.kde.kwalletd[2337]: kwalletd: Fatal IO error: client killed
acpid: 1 client rule loaded
org.kde.kuiserver[2337]: kuiserver: Fatal IO error: client killed
at-spi-bus-launcher[2994]: XIO:  fatal IO error 11 (Resource temporarily unavailable) on X server ":0"
at-spi-bus-launcher[2994]:       after 24042 requests (24042 known processed) with 3 events remaining.
systemd[2285]: pulseaudio.service: Main process exited, code=exited, status=1/FAILURE
systemd[2285]: pulseaudio.service: Failed with result 'exit-code'.
bluetoothd[1315]: Endpoint unregistered: sender=:1.146 path=/MediaEndpoint/A2DPSource
bluetoothd[1315]: Endpoint unregistered: sender=:1.146 path=/MediaEndpoint/A2DPSink
systemd[2285]: pulseaudio.service: Service RestartSec=100ms expired, scheduling restart.
systemd[2285]: pulseaudio.service: Scheduled restart job, restart counter is at 1.
systemd[2285]: Stopped Sound Service.
systemd[2285]: Starting Sound Service...
rtkit-daemon[2813]: Recovering from system lockup, not allowing further RT threads.
rtkit-daemon[2813]: message repeated 4 times: [ Recovering from system lockup, not allowing further RT threads.]
...