panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/main/kernel/sys/kern/kern_synch.c", line 955
Starting stack trace...
panic(ffffffff83381a45) at panic+0x1ba sys/kern/subr_prf.c:229
__assert(ffffffff833bbfdb,ffffffff834164ee,3bb,ffffffff833ef79b) at __assert+0x29 sys/kern/subr_prf.c:-1
refcnt_finalize(ffff80002a82b0c0,ffffffff8337861c) at refcnt_finalize+0x1c8 sys/kern/kern_synch.c:956
pppx_if_destroy(ffff800031d04000,ffff80002a82b0b8) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794
pppxclose(285b9a,41,2000,ffff80002a776a68) at pppxclose+0xa0 sys/net/if_pppx.c:541
spec_close(ffff80002a862d40) at spec_close+0x417 sys/kern/spec_vnops.c:-1
VOP_CLOSE(fffffd806afaf440,41,fffffd8007bfd478,ffff80002a776a68) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156
vn_closefile(fffffd806c9b7e10,ffff80002a776a68) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline]
vn_closefile(fffffd806c9b7e10,ffff80002a776a68) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615
fdrop(fffffd806c9b7e10,ffff80002a776a68) at fdrop+0x121 sys/kern/kern_descrip.c:1280

closef(fffffd806c9b7e10,ffff80002a776a68) at closef+0x190 sys/kern/kern_descrip.c:1264
syscall(ffff80002a862f90) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a862f90) at syscall+0x962 sys/arch/amd64/amd64/trap.c:775
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xe27e407e2d0, count: 245
End of stack trace.
syncing disks...set $lines = 0
set $maxwidth = 0
show panic
trace
show registers
show proc
ps
show all locks
show malloc
show all pools
machine ddbcpu 0
trace
machine ddbcpu 1
trace