criu c/r failed on qt gui demo & qt console demo on ubuntu

[oophelia]

Description

Steps to reproduce the issue:

1. build a qt gui demo & qt console demo on ubuntu
2. find the pidof
3. sudo criu dump -t 157888 --tcp-established --shell-job -o dump.log -v4 -D cp9

it is a very easy qt demo qt gui demo: it has a text showing seconds on mainwindow, every second +1; qt console demo: it prints text showing seconds in qt console, every second +1;

Describe the results you received: qt gui demo: dump failed, reports that "External socket is used". When using --ext-unix-sk, still dump failed, reports that "Can't dump half of a stream unix connection"

qt console demo: in log reports dump success and restore success. Actually not restore successfully.

Describe the results you expected: both demo could c/r success

Additional information you deem important (e.g. issue happens only occasionally):

CRIU logs and information:

CRIU full dump/restore logs:

qt gui demo dump sudo criu dump -t 189360 --tcp-established --shell-job -o dump.log -v4 -D gui-demo/ --ext-unix-sk

(00.041265) Obtaining task auvx ...
(00.041391) Dumping path for -3 fd via self 17 [/home/parallels/qt-project-test/build/Desktop_Qt_6_8_0-Release]
(00.041408) Dumping path for -3 fd via self 17 [/]
(00.041411) Dumping task cwd id 0xa4 root id 0xa5
(00.041453) Dumping file-locks
(00.041457) 
(00.041458) Dumping pstree (pid: 189360)
(00.041459) ----------------------------------------
(00.041459) Process: 189360(189360)
(00.041467) ----------------------------------------
(00.041494) cg: Dumping 1 sets
(00.041496) cg:    `- Dumping  of /user.slice/user-1000.slice/[email protected]/app.slice/app-org.gnome.Terminal.slice/vte-spawn-5a403202-721e-4166-bf85-eba3f2f2e72b.scope
(00.041497) cg:    `- Dumping name=zdtmtst of /
(00.041497) cg:    `- Dumping name=zdtmtst.defaultroot of /
(00.041503) cg: Writing CG image
(00.041518) unix: Dumping external sockets
(00.041527) unix: 	Dumping extern: ino 737870 peer_ino 737869 family    1 type    1 state  1 name /run/user/1000/bus
(00.041530) unix: 	Dumped extern: id 0xa6 ino 737870 peer 0 type 2 state 10 name 19 bytes
(00.041531) unix: 	Ext stream not supported: ino 737870 peer_ino 737869 family    1 type    1 state  1 name /run/user/1000/bus
(00.041532) Error (criu/sk-unix.c:881): unix: Can't dump half of stream unix connection. name: (null); peer name: /run/user/1000/bus
(00.041570) net: Unlock network
(00.041573) Unfreezing tasks into 1
(00.041574) 	Unseizing 189360 into 1
(00.041584) Error (criu/cr-dump.c:2111): Dumping FAILED.

qt console demo dump sudo criu dump -t 189917 --tcp-established --shell-job -o dump.log -v4 -D con3/

00.018022) Dumping pstree (pid: 189917)
(00.018023) ----------------------------------------
(00.018024) Process: 189917(189917)
(00.018057) ----------------------------------------
(00.018092) cg: Dumping 1 sets
(00.018095) cg:    `- Dumping  of /user.slice/user-1000.slice/[email protected]/app.slice/app-org.gnome.Terminal.slice/vte-spawn-5a403202-721e-4166-bf85-eba3f2f2e72b.scope
(00.018098) cg:    `- Dumping name=zdtmtst of /
(00.018099) cg:    `- Dumping name=zdtmtst.defaultroot of /
(00.018104) cg: Writing CG image
(00.018139) unix: Dumping external sockets
(00.018158) Writing image inventory (version 1)
(00.018249) Running post-dump scripts
(00.018261) Unfreezing tasks into 2
(00.018263) 	Unseizing 189917 into 2
(00.018623) Writing stats
(00.018653) Dumping finished successfully

qt console demo restore sudo criu restore --tcp-established --shell-job -o restore.log -v4 -D con3/

(00.020760) net: Unlock network
(00.020779) pie: 189917: seccomp: mode 0 on tid 189917
(00.025203) 189917 was trapped
(00.025215) 189917 was trapped
(00.025217) 189917 (native) is going to execute the syscall 139, required is 139
(00.025224) 189917 was stopped
(00.025236) 189917 was trapped
(00.025237) 189917 (native) is going to execute the syscall 215, required is 215
(00.025251) 189917 was stopped
(00.025256) Run late stage hook from criu master for external devices
(00.025257) restore late stage hook for external plugin failed
(00.025258) Running pre-resume scripts
(00.025261) Restore finished successfully. Tasks resumed.
(00.025262) Writing stats
(00.025295) Running post-resume scripts

Output of `criu --version`:

Version: 4.0
GitID: v4.0-33-gdd6b580b4

Output of `criu check --all`:

Warn  (criu/cr-check.c:824): Dirty tracking is OFF. Memory snapshot will not work.
Warn  (criu/cr-check.c:1259): Do not have API to map vDSO - will use mremap() to restore vDSO
Warn  (criu/cr-check.c:1179): CRIU built without CONFIG_COMPAT - can't C/R compatible tasks
Looks good but some kernel features are missing
which, depending on your process tree, may cause
dump or restore failure.

Additional environment details: