syzbot

panic: trap type 4, code=0, pc=ffffffff819e2dba
Starting stack trace...
panic(ffffffff8339fb3b) at panic+0x1d0 sys/kern/subr_prf.c:229
kerntrap(ffff80002a36af80) at kerntrap+0x30b
alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b
lf_advlock(ffff80000147db60,0,fffffd806b5e7d90,2,ffff80002a36b170,20) at lf_advlock+0x2fa ls_ref sys/kern/vfs_lockf.c:138 [inline]
lf_advlock(ffff80000147db60,0,fffffd806b5e7d90,2,ffff80002a36b170,20) at lf_advlock+0x2fa sys/kern/vfs_lockf.c:278
VOP_ADVLOCK(fffffd806e08b0d8,fffffd806b5e7d90,2,ffff80002a36b170,20) at VOP_ADVLOCK+0x87 sys/kern/vfs_vops.c:623
vn_closefile(fffffd806b5e7d90,ffff80003c455268) at vn_closefile+0xba sys/kern/vfs_vnops.c:615
fdrop(fffffd806b5e7d90,ffff80003c455268) at fdrop+0x121 sys/kern/kern_descrip.c:1267
closef(fffffd806b5e7d90,ffff80003c455268) at closef+0x192 sys/kern/kern_descrip.c:1251
fdfree(ffff80003c455268) at fdfree+0x116 sys/kern/kern_descrip.c:1182
exit1(ffff80003c455268,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215
sys_exit(ffff80003c455268,ffff80002a36b460,ffff80002a36b3b0) at sys_exit+0x1a sys/kern/kern_exit.c:-1
syscall(ffff80002a36b460) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline]
syscall(ffff80002a36b460) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0x7b234ebe1d10, count: 244
End of stack trace.