panic: kernel diagnostic assertion "vp->v_usecount == 0" failed: file "/syzkaller/managers/main/kernel/sys/kern/vfs_subr.c", line 639
Starting stack trace...
panic(ffffffff830a2e37) at panic+0x1ba sys/kern/subr_prf.c:229
__assert(ffffffff8305a8b0,ffffffff8309fdb5,27f,ffffffff82ff37bd) at __assert+0x29
vdoom(fffffd806a434bf0) at vdoom+0x105 sys/kern/vfs_subr.c:641
ufs_inactive(ffff8000311c2788) at ufs_inactive+0x188 sys/ufs/ufs/ufs_inode.c:89
VOP_INACTIVE(fffffd806a434bf0,ffff80002a4d6020) at VOP_INACTIVE+0xfe sys/kern/vfs_vops.c:495

vclean(fffffd806a434bf0,8,ffff80002a4d6020) at vclean+0x234 sys/kern/vfs_subr.c:1107
vgonel(fffffd806a434bf0,ffff80002a4d6020) at vgonel+0xec sys/kern/vfs_subr.c:1197
vop_generic_revoke(ffff8000311c2918) at vop_generic_revoke+0x32a sys/kern/vfs_default.c:105
VOP_REVOKE(fffffd80639e82b8,1) at VOP_REVOKE+0x65 sys/kern/vfs_vops.c:291
ptmioctl(5100,40287401,ffff8000311c2de0,3,ffff80002a4d6020) at ptmioctl+0x832 sys/kern/tty_pty.c:1172
VOP_IOCTL(fffffd806e049af8,40287401,ffff8000311c2de0,3,fffffd807f7d7618,ffff80002a4d6020) at VOP_IOCTL+0xa3 sys/kern/vfs_vops.c:264
vn_ioctl(fffffd806c695a60,40287401,ffff8000311c2de0,ffff80002a4d6020) at vn_ioctl+0xe8 sys/kern/vfs_vnops.c:525
sys_ioctl(ffff80002a4d6020,ffff8000311c2fc0,ffff8000311c2f10) at sys_ioctl+0x678
syscall(ffff8000311c2fc0) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x4643db01080, count: 242
End of stack trace.
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