panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 955 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 232057 17689 0 0x14000 0x200 0 reaper db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8344cb14) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8348ca0b,ffffffff83499b0a,3bb,ffffffff834c210f) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c3d7770,ffffffff834431fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:956 pppx_if_destroy(205b9a,ffff80003c3d7768) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80002a241ca0) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4095b0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8065fa5118,2,fffffd80097fd3a8,ffff80002a241ca0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806c27b868,ffff80002a241ca0) at fdrop+0x121 sys/kern/kern_descrip.c:1281 closef(fffffd806c27b868,ffff80002a241ca0) at closef+0x192 sys/kern/kern_descrip.c:1265 fdfree(ffff80002a241ca0) at fdfree+0x116 sys/kern/kern_descrip.c:1196 exit1(ffff80002a241ca0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002a241ca0,ffff80003c409920,ffff80003c409870) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c409910, count: 0 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 955 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8344cb14) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8348ca0b,ffffffff83499b0a,3bb,ffffffff834c210f) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c3d7770,ffffffff834431fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:956 pppx_if_destroy(205b9a,ffff80003c3d7768) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80002a241ca0) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4095b0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8065fa5118,2,fffffd80097fd3a8,ffff80002a241ca0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806c27b868,ffff80002a241ca0) at fdrop+0x121 sys/kern/kern_descrip.c:1281 closef(fffffd806c27b868,ffff80002a241ca0) at closef+0x192 sys/kern/kern_descrip.c:1265 fdfree(ffff80002a241ca0) at fdfree+0x116 sys/kern/kern_descrip.c:1196 exit1(ffff80002a241ca0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002a241ca0,ffff80003c409920,ffff80003c409870) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c409920) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c409920) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7c66a48dfb00, count: -16 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80003c409380 rbx 0xffff8000299bee07 rdx 0 rcx 0xffff80002a241ca0 rax 0xffff8000299bdff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x122fd34f305fe566 r11 0x259505aef3b170ca r12 0xffff8000299bec08 r13 0 r14 0 r15 0x1 rip 0xffffffff82f568f5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c409370 ss 0 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=34825 pid=56659 tcnt=0 stat=onproc flags process=1008 proc=2000 runpri=32, usrpri=78, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0xffff80002a241ca0 scnt=-1 ecnt=1 forw=0xffffffffffffffff, list=0xffff80002a240018,0xffff80003c41d260 process=0xffff8000fffe44f0 user=0xffff80003c404000, vmspace=0xfffffd806c87d9a0 estcpu=28, cpticks=9, pctcpu=0.6, user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 4477 205411 83401 0 2 0 syz-executor 4477 89533 83401 0 3 0x4000080 kqsel syz-executor 92126 426270 64312 0 3 0x80 nanoslp syz-executor 92126 497702 64312 0 3 0x4000080 lockf syz-executor 92126 348807 64312 0 3 0x4000000 smrbar syz-executor 58587 372735 54808 0 3 0x90 nanoslp syz-executor 58587 206242 54808 0 3 0x4000010 smrbar syz-executor 58587 404201 54808 0 3 0x4000090 fsleep syz-executor 45672 413285 76917 0 3 0x80 nanoslp syz-executor 45672 1855 76917 0 3 0x4000080 sbwait syz-executor 45672 481052 76917 0 3 0x4000080 fsleep syz-executor 47168 22321 86851 0 3 0x80 nanoslp syz-executor 47168 191625 86851 0 3 0x4000080 sbwait syz-executor 47168 182144 86851 0 3 0x4000000 inode syz-executor 47168 518198 86851 0 3 0x4000080 fsleep syz-executor 12692 339985 58828 0 3 0x80 nanoslp syz-executor 12692 407638 58828 0 3 0x4000080 dtread syz-executor 12692 382130 58828 0 3 0x4000080 fsleep syz-executor 91240 327698 70541 0 3 0x80 nanoslp syz-executor 91240 256628 70541 0 3 0x4000080 bell syz-executor 91240 162464 70541 0 3 0x4000080 fsleep syz-executor 91240 490654 70541 0 3 0x4000080 bell syz-executor 86851 197120 29305 0 3 0x82 nanoslp syz-executor 70541 46779 29305 0 3 0x82 nanoslp syz-executor 64312 766 29305 0 3 0x82 nanoslp syz-executor 58828 129312 29305 0 3 0x82 nanoslp syz-executor 83401 414224 29305 0 3 0x82 nanoslp syz-executor 76917 198711 29305 0 3 0x82 nanoslp syz-executor 54808 248312 29305 0 3 0x82 nanoslp syz-executor 34621 143224 29305 0 3 0x82 nanoslp syz-executor 29305 263610 37354 0 3 0x82 kqread syz-executor 37354 384909 23481 0 3 0x10008a sigsusp ksh 23481 56167 30717 0 3 0x98 kqread sshd-session 30717 434087 91648 0 3 0x92 kqread sshd-session 13026 514837 1 0 3 0x100083 ttyin getty 91648 238546 1 0 3 0x88 kqread sshd 41894 240537 34601 74 3 0x1100092 bpf pflogd 34601 115758 1 0 3 0x80 sbwait pflogd 84268 380345 35261 73 3 0x1100090 kqread syslogd 35261 401274 1 0 3 0x100082 sbwait syslogd 8528 71114 1 0 3 0x100080 kqread resolvd 89957 370692 74557 77 3 0x100092 kqread dhcpleased 83690 498623 74557 77 3 0x100092 kqread dhcpleased 74557 98244 1 0 3 0x80 kqread dhcpleased 34639 298312 0 0 3 0x14200 bored smr 18956 195357 0 0 3 0x14200 pgzero zerothread 76831 352608 0 0 3 0x14200 aiodoned aiodoned 78998 173075 0 0 3 0x14200 syncer update 421 150064 0 0 3 0x14200 cleaner cleaner 17689 232057 0 0 7 0x14200 reaper 90499 298541 0 0 3 0x14200 pgdaemon pagedaemon 17350 453647 0 0 3 0x14200 bored viomb 72434 481644 0 0 3 0x40014200 acpi0 acpi0 60801 24145 0 0 3 0x40014200 idle1 81174 301985 0 0 3 0x14200 bored softnet1 31448 227425 0 0 3 0x14200 bored softnet0 5611 490003 0 0 3 0x14200 bored systqmp 73762 357138 0 0 3 0x14200 bored systq 51908 191884 0 0 3 0x14200 tmoslp softclockmp 6320 101143 0 0 3 0x40014200 tmoslp softclock 81423 110995 0 0 3 0x40014200 idle0 1 201715 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 58587 (syz-executor) thread 0xffff8000fffe8550 (206242) exclusive rwlock clonelk r = 0 (0xffffffff8394ce28) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 if_clone_destroy+0x93 sys/net/if.c:-1 #3 ifioctl+0x59d sys/net/if.c:2160 #4 sys_ioctl+0x674 sys/kern/sys_generic.c:-1 #5 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #6 Xsyscall+0x128 Process 47168 (syz-executor) thread 0xffff80003c41ca88 (191625) exclusive rrwlock inode r = 0 (0xfffffd8067ce1ea8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline] #4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:159 #5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1232 #6 ufs_lookup+0x16bd sys/ufs/ufs/ufs_lookup.c:573 #7 VOP_LOOKUP+0x6e sys/kern/vfs_vops.c:85 #8 vfs_lookup+0x98a sys/kern/vfs_lookup.c:567 #9 namei+0x7ca sys/kern/vfs_lookup.c:250 #10 vn_open+0x15a sys/kern/vfs_vnops.c:140 #11 vndioctl+0xc43 sys/dev/vnd.c:458 #12 VOP_IOCTL+0xac sys/kern/vfs_vops.c:264 #13 vn_ioctl+0xf8 sys/kern/vfs_vnops.c:531 #14 sys_ioctl+0x674 sys/kern/sys_generic.c:-1 #15 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #15 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #16 Xsyscall+0x128 Process 47168 (syz-executor) thread 0xffff8000fffe8a80 (182144) exclusive rrwlock inode r = 0 (0xfffffd8067ce1c58) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vfs_lookup+0x11c sys/kern/vfs_lookup.c:-1 #6 namei+0x7ca sys/kern/vfs_lookup.c:250 #7 uipc_bind+0x328 sys/kern/uipc_usrreq.c:371 #8 sys_bind+0x2f6 sys/kern/uipc_syscalls.c:190 #9 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #9 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #10 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11100 12341K 12479K 166960K 12389 0 pcb 17 13K 14K 166960K 78 0 rtable 236 8K 9K 166960K 385 0 pf 44 19K 82K 166960K 69 0 ifaddr 44 7K 7K 166960K 56 0 ifgroup 63 2K 2K 166960K 76 0 sysctl 3 1K 9K 166960K 7 0 counters 80 38K 38K 166960K 98 0 ioctlops 0 0K 4K 166960K 1505 0 iov 1 4K 12K 166960K 6 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1424 90K 90K 166960K 1598 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 5 0 VM map 2 1K 1K 166960K 2 0 sem 8 0K 0K 166960K 8 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 93K 166960K 252 0 sigio 0 0K 0K 166960K 1 0 proc 72 115K 164K 166960K 560 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 28 0 in_multi 89 6K 6K 166960K 106 0 ether_multi 1 0K 0K 166960K 3 0 mrt 0 0K 0K 166960K 6 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 61 281K 281K 166960K 61 0 exec 0 0K 1K 166960K 392 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 256 167K 184K 166960K 4275 0 UVM aobj 6 2K 2K 166960K 7 0 pinsyscall 43 86K 102K 166960K 1399 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 4 0 NDP 15 0K 1K 166960K 36 0 temp 42 9075K 9139K 166960K 7504 0 kqueue 14 22K 28K 166960K 49 0 SYN cache 2 16K 16K 166960K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 26 0 0 1 0 1 1 0 8 0 rtpcb 120 39 0 35 1 0 1 1 0 8 0 rtentry 176 113 0 12 5 0 5 5 0 8 0 unpcb 144 161 0 138 4 0 4 4 0 8 3 syncache 336 4 0 4 1 0 1 1 0 8 1 tcpcb 736 46 0 40 1 0 1 1 0 8 0 arp 136 18 0 2 1 0 1 1 0 8 0 inpcb 328 218 0 208 4 0 4 4 0 8 3 nd6 152 24 0 3 1 0 1 1 0 8 0 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1192 12 0 9 1 0 1 1 0 8 0 pppxif 1576 1 0 0 1 0 1 1 0 8 0 pffrag 232 3 0 0 1 0 1 1 0 482 0 pffrnode 88 3 0 0 1 0 1 1 0 8 0 pffrent 40 4 0 1 1 0 1 1 0 8 0 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pftag 88 1 0 0 1 0 1 1 0 8 0 pfqueue 320 1 0 0 1 0 1 1 0 8 0 pfstitem 24 24 0 0 1 0 1 1 0 8 0 pfstkey 128 26 0 2 1 0 1 1 0 8 0 pfstate 448 25 0 1 3 0 3 3 0 8 0 pfrule 1360 22 0 16 2 1 1 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 458 0 44 29 0 29 29 0 8 1 art_table 40 460 0 44 5 0 5 5 0 8 0 art_node 32 113 0 21 1 0 1 1 0 8 0 sysvmsgpl 40 3 0 1 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 6 0 0 1 0 1 1 0 8 0 shmpl 112 4 0 1 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1802 0 332 93 0 93 93 0 8 0 ffsino 296 1802 0 332 114 0 114 114 0 8 0 nchpl 144 2159 0 446 64 0 64 64 0 8 0 rtmask 32 2 0 2 1 0 1 1 0 8 1 vnodes 216 2074 0 0 116 0 116 116 0 8 0 namei 1024 6990 0 6989 2 0 2 2 0 8 1 percpumem 16 64 0 9 1 0 1 1 0 8 0 kstatmem 264 44 0 10 3 0 3 3 0 8 0 scsiplug 72 1 0 1 1 0 1 1 0 8 1 scxspl 216 7164 0 7164 3 2 1 2 1 8 1 plimitpl 152 46 0 27 1 0 1 1 0 8 0 sigapl 424 566 0 518 7 0 7 7 0 8 1 knotepl 120 297 0 0 9 0 9 9 0 8 0 kqueuepl 224 71 0 56 2 0 2 2 0 8 0 pipepl 344 133 0 106 3 0 3 3 0 8 0 fdescpl 528 550 0 518 3 0 3 3 0 8 0 filepl 160 2622 0 2379 17 0 17 17 0 8 5 lockfpl 104 60 0 52 1 0 1 1 0 8 0 lockfspl 48 32 0 25 1 0 1 1 0 8 0 sessionpl 144 26 0 17 1 0 1 1 0 8 0 pgrppl 48 38 0 21 1 0 1 1 0 8 0 ucredpl 104 213 0 198 1 0 1 1 0 8 0 zombiepl 144 519 0 518 1 0 1 1 0 8 0 processpl 1232 566 0 518 5 0 5 5 0 8 0 procpl 664 793 0 730 6 0 6 6 0 8 0 sosppl 176 1 0 1 1 0 1 1 0 8 1 sockpl 752 420 0 382 14 3 11 14 0 8 6 mcl64k 65536 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 126 0 0 16 0 16 16 0 8 0 mcl2k 2048 20 0 0 3 0 3 3 0 8 0 mtagpl 96 4 0 0 1 0 1 1 0 8 0 mbufpl 256 136 0 0 9 0 9 9 0 8 0 bufpl 280 2558 0 107 176 0 176 176 0 8 0 anonpl 32 3828 0 0 31 0 31 31 0 246 0 amapchunkpl 152 12597 0 12045 26 0 26 26 0 158 4 amappl16 200 1891 0 1864 5 2 3 5 0 8 0 amappl15 192 5 0 5 1 1 0 1 0 8 0 amappl14 184 428 0 427 1 0 1 1 0 8 0 amappl13 176 125 0 113 1 0 1 1 0 8 0 amappl12 168 800 0 769 2 0 2 2 0 8 0 amappl11 160 21 0 21 1 1 0 1 0 8 0 amappl10 152 69 0 55 1 0 1 1 0 8 0 amappl9 144 281 0 281 1 1 0 1 0 8 0 amappl8 136 115 0 113 1 0 1 1 0 8 0 amappl7 128 150 0 137 1 0 1 1 0 8 0 amappl6 120 154 0 153 1 0 1 1 0 8 0 amappl5 112 98 0 88 1 0 1 1 0 8 0 amappl4 104 291 0 271 1 0 1 1 0 8 0 amappl3 96 2241 0 2114 4 0 4 4 0 8 0 amappl2 88 528 0 467 2 0 2 2 0 8 0 amappl1 80 10243 0 9633 16 0 16 16 0 8 0 amappl 88 3542 0 3359 5 0 5 5 0 92 0 uvmvnodes 80 103 0 0 3 0 3 3 0 8 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 6 0 6 1 1 0 1 0 8 0 dma128 128 254 0 254 2 1 1 1 0 8 1 dma64 64 6 0 6 1 1 0 1 0 8 0 dma32 32 7 0 7 1 1 0 1 0 8 0 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 6 0 1 1 0 1 1 0 8 0 uaddrrnd 24 550 0 518 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 550 0 518 1 0 1 1 0 8 0 vmmpekpl 168 6389 0 6353 2 0 2 2 0 8 0 vmmpepl 168 43394 0 41405 97 0 97 97 0 357 5 vmsppl 488 549 0 518 5 0 5 5 0 8 0 rwobjpl 80 15362 0 14297 26 0 26 26 0 8 2 pdppl 4096 1107 0 1036 103 28 75 85 0 8 4 pvpl 32 11957 0 0 97 0 97 97 0 265 0 pmappl 256 549 0 518 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 275 0 31 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff83879ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_release_all(ffffffff83a18580) at __mp_release_all+0xd8 sys/kern/kern_lock.c:223 msleep_nsec(ffffffff838a4448,ffffffff838a4410,4,ffffffff8345f9c7,ffffffffffffffff) at msleep_nsec+0x1e1 sys/kern/kern_synch.c:-1 reaper(ffff8000ffffd9f8) at reaper+0x15b sys/kern/kern_exit.c:477 end trace frame: 0x0, count: 9 ddb{0}> trace x86_ipi_db(ffffffff83879ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 __mp_release_all(ffffffff83a18580) at __mp_release_all+0xd8 sys/kern/kern_lock.c:223 msleep_nsec(ffffffff838a4448,ffffffff838a4410,4,ffffffff8345f9c7,ffffffffffffffff) at msleep_nsec+0x1e1 sys/kern/kern_synch.c:-1 reaper(ffff8000ffffd9f8) at reaper+0x15b sys/kern/kern_exit.c:477 end trace frame: 0x0, count: -6 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x25: addq $0x8,%rsp db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8344cb14) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8348ca0b,ffffffff83499b0a,3bb,ffffffff834c210f) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c3d7770,ffffffff834431fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:956 pppx_if_destroy(205b9a,ffff80003c3d7768) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80002a241ca0) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4095b0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8065fa5118,2,fffffd80097fd3a8,ffff80002a241ca0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806c27b868,ffff80002a241ca0) at fdrop+0x121 sys/kern/kern_descrip.c:1281 closef(fffffd806c27b868,ffff80002a241ca0) at closef+0x192 sys/kern/kern_descrip.c:1265 fdfree(ffff80002a241ca0) at fdfree+0x116 sys/kern/kern_descrip.c:1196 exit1(ffff80002a241ca0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002a241ca0,ffff80003c409920,ffff80003c409870) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c409910, count: 0 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff8344cb14) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff8348ca0b,ffffffff83499b0a,3bb,ffffffff834c210f) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c3d7770,ffffffff834431fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:956 pppx_if_destroy(205b9a,ffff80003c3d7768) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80002a241ca0) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4095b0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd8065fa5118,2,fffffd80097fd3a8,ffff80002a241ca0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806c27b868,ffff80002a241ca0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806c27b868,ffff80002a241ca0) at fdrop+0x121 sys/kern/kern_descrip.c:1281 closef(fffffd806c27b868,ffff80002a241ca0) at closef+0x192 sys/kern/kern_descrip.c:1265 fdfree(ffff80002a241ca0) at fdfree+0x116 sys/kern/kern_descrip.c:1196 exit1(ffff80002a241ca0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002a241ca0,ffff80003c409920,ffff80003c409870) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c409920) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c409920) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7c66a48dfb00, count: -16