panic: Assertion lock == sq->sq_lock failed at /syzkaller/managers/main/kernel/sys/kern/subr_sleepqueue.c:LINE

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: 09ef4172 Revert r347469.
git tree: freebsd
console output: https://syzkaller.appspot.com/x/log.txt?x=10aad622a00000
dashboard link: https://syzkaller.appspot.com/bug?extid=bf7fb36aa464542afc37

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+bf7fb3...@syzkaller.appspotmail.com

panic: Assertion lock == sq->sq_lock failed at
/syzkaller/managers/main/kernel/sys/kern/subr_sleepqueue.c:360
cpuid = 0
time = 4197332
KDB: stack backtrace:
db_trace_self_wrapper() at db_trace_self_wrapper+0x47/frame
0xfffffe002ae57600
vpanic() at vpanic+0x1e0/frame 0xfffffe002ae57660
panic() at panic+0x43/frame 0xfffffe002ae576c0
sleepq_add() at sleepq_add+0x48e/frame 0xfffffe002ae57720
_sleep() at _sleep+0x2ce/frame 0xfffffe002ae577d0
kern_sigtimedwait() at kern_sigtimedwait+0x4ae/frame 0xfffffe002ae578d0
sys_sigwaitinfo() at sys_sigwaitinfo+0x5c/frame 0xfffffe002ae57980
amd64_syscall() at amd64_syscall+0x436/frame 0xfffffe002ae57ab0
fast_syscall_common() at fast_syscall_common+0x101/frame 0xfffffe002ae57ab0
--- syscall (346, FreeBSD ELF64, sys_sigwaitinfo), rip = 0x20000249, rsp =
0x7fffdfed4eb8, rbp = 0xa ---
KDB: enter: panic
[ thread pid 65815 tid 101950 ]
Stopped at kdb_enter+0x6a: movq $0,kdb_why


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[syzbot]

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