assertion failed: child->ppid == parent->pid

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 76e8476b kconfig: use pkg-config for ncurses detection
git tree: akaros
console output: https://syzkaller.appspot.com/x/log.txt?x=138f85c6e00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b018fab5edd31b3
dashboard link: https://syzkaller.appspot.com/bug?extid=f4a9a327d116a18d8ad7

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+f4a9a3...@syzkaller.appspotmail.com

kernel panic at kern/src/process.c:986, from core 0: assertion failed:
child->ppid == parent->pid
Stack Backtrace on Core 0:
#01 [<0xffffffffc200a7fc>] in backtrace at src/kdebug.c:235
#02 [<0xffffffffc2009f95>] in _panic at src/init.c:275
#03 [<0xffffffffc204bfe7>] in __proc_disown_child at src/process.c:986
#04 [< [inline] >] in proc_disown_children at src/process.c:844
#04 [<0xffffffffc204d35e>] in proc_destroy at src/process.c:932
#05 [<0xffffffffc2058c36>] in sys_proc_destroy at src/syscall.c:852
#06 [<0xffffffffc2059f49>] in syscall at src/syscall.c:2582
#07 [<0xffffffffc205aad8>] in run_local_syscall at src/syscall.c:2619
#08 [<0xffffffffc205b019>] in prep_syscalls at src/syscall.c:2639
#09 [<0xffffffffc20b6282>] in sysenter_callwrapper at arch/x86/trap.c:926


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.