panic: kernel diagnostic assertion "vp->v_usecount == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/vfs_subr.c", line 639
Starting stack trace...
panic(ffffffff830d710a) at panic+0x1d0 sys/kern/subr_prf.c:229
__assert(ffffffff8308c51e,ffffffff830af90e,27f,ffffffff8302bc90) at __assert+0x29
vdoom(fffffd807de209a8) at vdoom+0x105 sys/kern/vfs_subr.c:641
ufs_inactive(ffff80002a09a5b8) at ufs_inactive+0x188 sys/ufs/ufs/ufs_inode.c:89
VOP_INACTIVE(fffffd807de209a8,ffff8000ffff71d8) at VOP_INACTIVE+0x107 sys/kern/vfs_vops.c:495
vclean(fffffd807de209a8,8,ffff8000ffff71d8) at vclean+0x234 sys/kern/vfs_subr.c:1107
vgonel(fffffd807de209a8,ffff8000ffff71d8) at vgonel+0xec sys/kern/vfs_subr.c:1197
vop_generic_revoke(ffff80002a09a748) at vop_generic_revoke+0x32a sys/kern/vfs_default.c:105
VOP_REVOKE(fffffd807de207f8,1) at VOP_REVOKE+0x65 sys/kern/vfs_vops.c:291
ptmioctl(5100,40287401,ffff80002a09ac10,3,ffff8000ffff71d8) at ptmioctl+0x832 sys/kern/tty_pty.c:1172
VOP_IOCTL(fffffd806dd451b8,40287401,ffff80002a09ac10,3,fffffd807f7d37b8,ffff8000ffff71d8) at VOP_IOCTL+0xac sys/kern/vfs_vops.c:264
vn_ioctl(fffffd80648543a8,40287401,ffff80002a09ac10,ffff8000ffff71d8) at vn_ioctl+0xf6 sys/kern/vfs_vnops.c:525
sys_ioctl(ffff8000ffff71d8,ffff80002a09adf0,ffff80002a09ad40) at sys_ioctl+0x67c
syscall(ffff80002a09adf0) at syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:179 [inline]
syscall(ffff80002a09adf0) at syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x6b7fb11c300, count: 242
End of stack trace.