panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/main/kernel/sys/kern/kern_synch.c", line 953 Starting stack trace... panic(ffffffff8333a8ae) at panic+0x1ba sys/kern/subr_prf.c:229 __assert(ffffffff8337ac72,ffffffff833d8a72,3b9,ffffffff833b2687) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80002a8b9b20,ffffffff83332843) at refcnt_finalize+0x1c8 sys/kern/kern_synch.c:954 pppx_if_destroy(205b9a,ffff80002a8b9b18) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,20 00,ffff80002a820a88) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80002a90d090) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805e201560,1,fffffd8007bfb618,ffff80002a820a88) at VOP_CLOSE+0x129 sys/kern/vfs_vops.c:156 vn_closefile(fffffd80789aac38,ffff80002a820a88) at vn_closefile+0x11d vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd80789aac38,ffff80002a820a88) at vn_closefile+0x11d sys/kern/vfs_vnops.c:615 fdrop(fffffd80789aac38,ffff80002a820a88) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd80789aac38,ffff80002a820a88) at closef+0x190 sys/kern/kern_descrip.c:1264 fdfree(ffff80002a820a88) at fdfree+0x115 sys/kern/kern_descrip.c:1195 exit1(ffff80002a820a88,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002a820a88,ffff80002a90d3f0,ffff80002a90d340) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80002a90d3f0) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80002a90d3f0) at syscall+0x962 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6f9c50c96bb0, 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