panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/main/kernel/sys/kern/kern_synch.c", line 944 Star ting stack trace... panic(ffffffff8340849f) at panic+0x1ba sys/kern/subr_prf.c:229 __assert(ffffffff833b39b0,ffffffff832fb584,3b0,ffffffff833b44d7) at __assert+0x29 refcnt_finalize(ffff80002a7c75e0,ffffffff832fdb8d) at refcnt_finalize+0x1c8 sys/kern/kern_synch.c:945 pppx_if_destroy(205b92,ffff80002a7c75d8) at pppx_if_destroy+0x3d sys/net/if_pppx.c:806 pppxclose(205b92,1,2000,ffff80002a85dc78) at pppxclose+0xa0 sys/net/if_pppx.c:553 spec_close(ffff80003892cd00) at spec_close+0x412 VOP_CLOSE(fffffd805f3d6a58,1,fffffd807f7d77b8,ffff80002a85dc78) at VOP_CLOSE+0x12a sys/kern/vfs_vops.c:156 vn_closefile(fffffd80661c5090,ffff80002a85dc78) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd80661c5090,ffff80002a85dc78) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd80661c5090,ffff80002a85dc78) at fdrop+0x126 sys/kern/kern_descrip.c:1265 closef(fffffd80661c5090,ffff80002a85dc78) at closef+0x18d sys/kern/kern_descrip.c:1249 fdfree(ffff80002a85dc78) at fdfree+0x115 sys/kern/kern_descrip.c:1181 exit1(ffff80002a85dc78,0,0,1) at exit1+0x57f sys/kern/kern_exit.c:216 sys_exit(ffff80002a85dc78,ffff80003892d070,ffff80003892cfc0) at sys_exit+0x1a syscall(ffff80003892d070) at syscall+0x97e sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x719480006d10, count: 242 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