assert "kd_lookup(kd->kd_unit) == NULL" failed in kcov.c (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 705b70e045d6 Implement support for SVE (Scalable Vector Ex..
git tree: openbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=1082c718580000
kernel config: https://syzkaller.appspot.com/x/.config?x=1bc15e68cd2a49e5
dashboard link: https://syzkaller.appspot.com/bug?extid=80d4b47080e55b8cfadf

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/444b4c9b550d/disk-705b70e0.raw.xz
bsd.gdb: https://storage.googleapis.com/syzbot-assets/ebab7a12fb13/bsd-705b70e0.gdb.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a8f37474f8dd/kernel-705b70e0.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+80d4b4...@syzkaller.appspotmail.com

panic: kernel diagnostic assertion "kd_lookup(kd->kd_unit) == NULL" failed: file "/syzkaller/managers/main/kernel/sys/dev/kcov.c", line 306
Starting stack trace...
panic(ffffffff83405dd0) at panic+0x1ba sys/kern/subr_prf.c:229
__assert(ffffffff833b3398,ffffffff8333bf47,132,ffffffff83393530) at __assert+0x29
kcovopen(113d4,e2,2000,ffff80002a802540) at kcovopen+0x14f kd_lookup sys/dev/kcov.c:478 [inline]
kcovopen(113d4,e2,2000,ffff80002a802540) at kcovopen+0x14f sys/dev/kcov.c:306
spec_open_clone(ffff80002a7d0e98) at spec_open_clone+0x287 sys/kern/spec_vnops.c:722
spec_open(ffff80002a7d0e98) at spec_open+0x326 sys/kern/spec_vnops.c:148
VOP_OPEN(fffffd806a3160f8,e2,fffffd807f7d7958,ffff80002a802540) at VOP_OPEN+0x82 sys/kern/vfs_vops.c:138
vn_open(ffff80002a7d10e8,2e2,0) at vn_open+0x708 sys/kern/vfs_vnops.c:177
doopenat(ffff80002a802540,ffffff9c,4000000001c0,2e1,0,ffff80002a7d1290) at doopenat+0x31d sys/kern/vfs_syscalls.c:1124
syscall(ffff80002a7d1340) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x3a4d439df90, count: 247
End of stack trace.


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[syzbot]

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