panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 951 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 229447 51302 77 0x100012 0x1 0 dhcpleased db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83375fb7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b1280,ffffffff833c36e2,3b7,ffffffff833ed569) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4ce370,ffffffff8336b8fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4ce368) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff80002f404570) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c44abf0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805e281d98,1,fffffd80097fb548,ffff80002f404570) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd807a275aa8,ffff80002f404570) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd807a275aa8,ffff80002f404570) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80002f404570) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80002f404570,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002f404570,ffff80003c44af60,ffff80003c44aeb0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c44af50, 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 951 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83375fb7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b1280,ffffffff833c36e2,3b7,ffffffff833ed569) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4ce370,ffffffff8336b8fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4ce368) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff80002f404570) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c44abf0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805e281d98,1,fffffd80097fb548,ffff80002f404570) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd807a275aa8,ffff80002f404570) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd807a275aa8,ffff80002f404570) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80002f404570) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80002f404570,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002f404570,ffff80003c44af60,ffff80003c44aeb0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c44af60) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c44af60) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7a2ea87a0d20, count: -16 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80003c44a9c0 rbx 0xffff8000299eeddf rdx 0 rcx 0xffff80002f404570 rax 0xffff8000299edff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x60b280692b4b2841 r11 0xac277bd68884462e r12 0xffff8000299eebe0 r13 0 r14 0 r15 0x1 rip 0xffffffff81cb5af5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c44a9b0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=245295 pid=20755 tcnt=0 stat=onproc flags process=1018 proc=2000 runpri=32, usrpri=86, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0xffff80002f404570 scnt=-1 ecnt=1 forw=0xffffffffffffffff, list=0xffff80003c45a2c0,0xffff80002f405cd8 process=0xffff80003a825880 user=0xffff80003c446000, vmspace=0xfffffd806b9b5b88 estcpu=36, cpticks=4, pctcpu=0.0, user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 24335 155689 6869 0 3 0x80 nanoslp syz-executor 24335 508019 6869 0 2 0x4000000 syz-executor 24335 294982 6869 0 3 0x4000080 fsleep syz-executor 24335 389954 6869 0 3 0x4000080 fsleep syz-executor 80738 173055 36305 0 3 0x80 nanoslp syz-executor 80738 252060 36305 0 3 0x4000080 fsleep syz-executor 80738 480405 36305 0 3 0x4000080 kqsel syz-executor 80738 280563 36305 0 3 0x4000080 fsleep syz-executor 60782 93098 30332 0 3 0x3000 suspend syz-executor 60782 130750 30332 0 3 0x4081000 biowait syz-executor 38038 353638 28971 0 3 0x82 nanoslp syz-executor 15508 340961 28971 0 3 0x82 piperd syz-executor 30332 243564 28971 0 3 0x82 nanoslp syz-executor 36305 152734 28971 0 3 0x82 nanoslp syz-executor 18543 473478 1 0 3 0x100083 ttyopn getty 5482 79315 0 0 3 0x14200 bored sosplice 86781 340342 28971 0 3 0x82 wait syz-executor 96157 305249 28971 0 3 0x82 piperd syz-executor 6869 155906 28971 0 3 0x82 nanoslp syz-executor 28971 489578 32069 0 3 0x82 wait syz-executor 32069 295843 59913 0 3 0x10008a sigsusp ksh 59913 408671 38411 0 3 0x98 kqread sshd-session 38411 114664 73661 0 3 0x92 kqread sshd-session 73661 190321 1 0 3 0x88 kqread sshd 5153 98786 80362 74 3 0x1100092 bpf pflogd 80362 136288 1 0 3 0x80 sbwait pflogd 87500 301248 89205 73 3 0x1100090 kqread syslogd 89205 219886 1 0 3 0x100082 sbwait syslogd 91024 153155 1 0 2 0x100000 resolvd 34945 462455 88506 77 2 0x100012 dhcpleased 51302 229447 88506 77 7 0x100013 dhcpleased 88506 439046 1 0 3 0x80 kqread dhcpleased 37583 511332 0 0 3 0x14200 bored smr 43167 13418 0 0 3 0x14200 pgzero zerothread 43633 209842 0 0 3 0x14200 aiodoned aiodoned 2099 210253 0 0 3 0x14200 syncer update 21701 462674 0 0 3 0x14200 cleaner cleaner 61247 188085 0 0 3 0x14200 reaper reaper 85040 103678 0 0 3 0x14200 pgdaemon pagedaemon 20121 135015 0 0 3 0x14200 bored viomb 947 385693 0 0 3 0x40014200 acpi0 acpi0 15781 42514 0 0 3 0x40014200 idle1 31442 159026 0 0 3 0x14200 bored softnet7 45859 123724 0 0 3 0x14200 bored softnet6 20902 330749 0 0 3 0x14200 bored softnet5 13397 66288 0 0 3 0x14200 bored softnet4 19064 306851 0 0 3 0x14200 bored softnet3 85749 301294 0 0 3 0x14200 bored softnet2 13845 381864 0 0 3 0x14200 bored softnet1 43635 59475 0 0 2 0x14200 softnet0 65961 5380 0 0 2 0x14200 systqmp 12268 512358 0 0 3 0x14200 bored systq 99188 244326 0 0 3 0x14200 tmoslp softclockmp 24723 115890 0 0 3 0x40014200 tmoslp softclock 78550 8340 0 0 3 0x40014200 idle0 1 123732 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 60782 (syz-executor) thread 0xffff80002f4042d8 (130750) Process 43635 (softnet0) thread 0xffff8000ffffea60 (59475) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10276 11202K 12012K 166960K 16433 0 pcb 17 16K 32K 166960K 888 0 rtable 222 12K 13K 166960K 854 0 pf 49 20K 67488K 166960K 427 0 ifaddr 45 8K 8K 166960K 212 0 ifgroup 70 2K 3K 166960K 361 0 sysctl 4 1K 9K 166960K 28 0 counters 78 38K 39K 166960K 426 0 ioctlops 0 0K 4K 166960K 2242 0 iov 0 0K 20K 166960K 328 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1485 93K 94K 166960K 4686 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 39 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 105 0 dirhash 12 2K 2K 166960K 69 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 15 53K 236K 166960K 3279 0 sigio 1 0K 0K 166960K 92 0 proc 72 115K 163K 166960K 1091 0 subproc 72 4K 4K 166960K 135 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 371 0 in_multi 79 5K 7K 166960K 309 0 ether_multi 1 0K 0K 166960K 37 0 mrt 2 0K 0K 166960K 14 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 271 1208K 1208K 166960K 271 0 exec 0 0K 1K 166960K 1019 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 5 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 231 152K 171K 166960K 32200 0 UVM aobj 42 4K 6K 166960K 48 0 pinsyscall 40 80K 107K 166960K 4568 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 1 0K 1K 166960K 251 0 NDP 18 0K 2K 166960K 150 0 temp 89 8652K 8766K 166960K 166027 0 kqueue 15 24K 31K 166960K 618 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 120 403 0 398 4 3 1 3 0 8 0 rtentry 176 264 0 186 5 1 4 5 0 8 0 unpcb 144 2504 0 2480 19 17 2 6 0 8 1 syncache 336 6 0 6 3 2 1 1 0 8 1 tcpqe 32 1 0 1 1 0 1 1 0 8 1 tcpcb 736 1160 0 1155 38 31 7 7 0 8 5 arp 128 32 0 20 1 0 1 1 0 8 0 ipq 40 1 0 1 1 1 0 1 0 8 0 ipqe 40 3 0 3 1 1 0 1 0 8 0 inpcb 328 3502 0 3492 45 35 10 10 0 8 8 nd6 144 42 0 28 1 0 1 1 0 8 0 pkpcb 40 22 0 22 6 5 1 1 0 8 1 kcovpl 48 15 0 7 1 0 1 1 0 8 0 mppekey 1024 6 0 6 2 2 0 1 0 8 0 ppxss 1192 146 0 144 4 3 1 1 0 8 0 pppxif 1504 14 0 13 6 5 1 1 0 8 0 pfstscr 40 10 0 8 4 3 1 1 0 8 0 pffrag 232 55 0 48 2 1 1 1 0 482 0 pffrnode 88 55 0 48 2 1 1 1 0 8 0 pffrent 40 105 0 97 2 1 1 1 0 8 0 pfosfp 40 1429 0 1429 5 1 4 5 0 8 4 pfosfpen 112 1429 0 1429 21 1 20 21 0 8 20 pfrktable 1344 4 0 4 2 1 1 1 0 8 1 pfanchor 1288 4 0 0 1 0 1 1 0 8 0 pftag 88 3 0 0 1 0 1 1 0 8 0 pfstitem 24 201 0 114 1 0 1 1 0 8 0 pfstkey 128 219 0 131 3 0 3 3 0 8 0 pfstate 384 209 0 122 9 0 9 9 0 8 0 pfrule 1344 207 0 201 2 1 1 2 0 8 0 rttmr 136 2 0 2 2 2 0 1 0 8 0 art_heap8 4096 4 0 0 4 0 4 4 0 8 0 art_heap4 256 1302 0 908 38 13 25 28 0 8 0 art_table 40 1306 0 908 5 0 5 5 0 8 0 art_node 32 255 0 187 1 0 1 1 0 8 0 sysvmsgpl 40 2 0 2 2 2 0 1 0 8 0 semupl 112 2 0 2 2 1 1 1 0 8 1 semapl 112 100 0 90 1 0 1 1 0 8 0 shmpl 112 45 0 6 2 0 2 2 0 8 0 dirhash 1024 56 0 39 3 0 3 3 0 8 0 dino2pl 256 7602 0 6082 96 0 96 96 0 8 0 ffsino 296 7602 0 6082 118 0 118 118 0 8 0 nchpl 144 12095 0 10381 64 0 64 64 0 8 0 rtmask 32 33 0 33 6 6 0 1 0 8 0 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 43642 0 43642 5 4 1 2 0 8 1 percpumem 16 228 0 174 1 0 1 1 0 8 0 kstatmem 264 246 0 208 5 2 3 4 0 8 0 acpiwqpl 32 1 0 1 1 0 1 1 1 8 1 scsiplug 72 18 0 18 7 7 0 1 0 8 0 scxspl 216 79360 0 79359 20 18 2 8 1 8 1 plimitpl 152 833 0 814 1 0 1 1 0 8 0 sigapl 424 3588 0 3536 9 1 8 9 0 8 0 knotepl 120 584 0 0 17 0 17 17 0 8 0 kqueuepl 224 1391 0 1377 16 14 2 5 0 8 1 pipepl 344 592 0 563 9 6 3 9 0 8 0 fdescpl 528 3539 0 3510 3 0 3 3 0 8 0 filepl 160 25213 0 24979 40 26 14 18 0 8 2 lockfpl 104 2310 0 2307 5 3 2 3 0 8 1 lockfspl 48 887 0 884 1 0 1 1 0 8 0 sessionpl 144 31 0 22 1 0 1 1 0 8 0 pgrppl 48 126 0 109 1 0 1 1 0 8 0 ucredpl 104 3608 0 3594 1 0 1 1 0 8 0 zombiepl 144 4758 0 4754 1 0 1 1 0 8 0 processpl 1248 3588 0 3536 6 1 5 6 0 8 0 procpl 664 9131 0 9072 9 2 7 8 0 8 0 sosppl 168 29 0 29 7 6 1 1 0 8 1 sockpl 752 6620 0 6581 70 58 12 17 0 8 7 mcl64k 65536 13 0 0 2 0 2 2 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 3 0 0 1 0 1 1 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 4 0 0 1 0 1 1 0 8 0 mcl4k 4096 119 0 0 15 0 15 15 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 68 0 0 6 0 6 6 0 8 0 mtagpl 96 22 0 0 1 0 1 1 0 8 0 mbufpl 256 1227 0 0 74 0 74 74 0 8 0 bufpl 280 31434 0 25291 440 0 440 440 0 8 0 anonpl 32 12914 0 0 104 0 104 104 0 246 0 amapchunkpl 152 109099 0 108619 87 48 39 39 0 158 16 amappl16 200 12838 0 12668 97 76 21 27 0 8 9 amappl15 192 6 0 6 2 2 0 1 0 8 0 amappl14 184 151 0 139 1 0 1 1 0 8 0 amappl13 176 8 0 7 2 1 1 1 0 8 0 amappl12 168 4314 0 4285 4 2 2 3 0 8 0 amappl11 160 52 0 38 1 0 1 1 0 8 0 amappl10 152 7 0 7 2 2 0 1 0 8 0 amappl9 144 251 0 250 2 1 1 1 0 8 0 amappl8 136 22 0 18 1 0 1 1 0 8 0 amappl7 128 126 0 113 1 0 1 1 0 8 0 amappl6 120 255 0 251 1 0 1 1 0 8 0 amappl5 112 154 0 144 1 0 1 1 0 8 0 amappl4 104 341 0 320 1 0 1 1 0 8 0 amappl3 96 22572 0 22467 4 0 4 4 0 8 0 amappl2 88 776 0 710 2 0 2 2 0 8 0 amappl1 80 21787 0 21194 15 0 15 15 0 8 0 amappl 88 30833 0 30674 5 0 5 5 0 92 0 dma16384 16384 1 0 1 1 1 0 1 0 8 0 dma8192 8192 1 0 1 1 1 0 1 0 8 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma1024 1024 2 0 1 1 0 1 1 0 8 0 dma512 512 1 0 1 1 1 0 1 0 8 0 dma256 256 7 0 7 2 2 0 1 0 8 0 dma128 128 256 0 256 4 4 0 1 0 8 0 dma64 64 10 0 10 5 4 1 1 0 8 1 dma32 32 8 0 8 2 2 0 1 0 8 0 dma16 16 19 0 18 1 0 1 1 0 8 0 aobjpl 72 47 0 6 1 0 1 1 0 8 0 uaddrrnd 24 3540 0 3511 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3540 0 3511 1 0 1 1 0 8 0 vmmpekpl 168 27557 0 27501 3 0 3 3 0 8 0 vmmpepl 168 224753 0 222691 154 45 109 110 0 357 4 vmsppl 488 3539 0 3511 6 1 5 5 0 8 0 rwobjpl 80 63782 0 56734 159 9 150 152 0 8 1 pdppl 4096 7088 0 7022 118 44 74 88 0 8 8 pvpl 32 21411 0 0 172 0 172 172 0 265 0 pmappl 256 3539 0 3511 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 416 0 102 9 0 9 9 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8382eff0) 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_lock(ffffffff838d7f60) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff838d7f60) at __mp_lock+0x192 sys/kern/kern_lock.c:165 intr_handler(ffff80002a2a0830,ffff800000079a80) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:559 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x4f sys/dev/kcov.c:159 ktrgenio(ffff8000ffff2540,5,0,ffff800000b384a0,14) at ktrgenio+0x228 ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrgenio(ffff8000ffff2540,5,0,ffff800000b384a0,14) at ktrgenio+0x228 sys/kern/kern_ktrace.c:264 dofilereadv(ffff8000ffff2540,5,ffff80002a2a0b60,0,ffff80002a2a0c20) at dofilereadv+0x474 sys/kern/sys_generic.c:268 sys_readv(ffff8000ffff2540,ffff80002a2a0cd0,ffff80002a2a0c20) at sys_readv+0xd8 sys/kern/sys_generic.c:199 syscall(ffff80002a2a0cd0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a2a0cd0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x73edd5b07350, count: 3 ddb{0}> trace x86_ipi_db(ffffffff8382eff0) 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_lock(ffffffff838d7f60) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff838d7f60) at __mp_lock+0x192 sys/kern/kern_lock.c:165 intr_handler(ffff80002a2a0830,ffff800000079a80) at intr_handler+0xe9 sys/arch/amd64/amd64/intr.c:559 Xintr_ioapic_edge23_untramp() at Xintr_ioapic_edge23_untramp+0x18f __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x4f sys/dev/kcov.c:159 ktrgenio(ffff8000ffff2540,5,0,ffff800000b384a0,14) at ktrgenio+0x228 ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrgenio(ffff8000ffff2540,5,0,ffff800000b384a0,14) at ktrgenio+0x228 sys/kern/kern_ktrace.c:264 dofilereadv(ffff8000ffff2540,5,ffff80002a2a0b60,0,ffff80002a2a0c20) at dofilereadv+0x474 sys/kern/sys_generic.c:268 sys_readv(ffff8000ffff2540,ffff80002a2a0cd0,ffff80002a2a0c20) at sys_readv+0xd8 sys/kern/sys_generic.c:199 syscall(ffff80002a2a0cd0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a2a0cd0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x73edd5b07350, count: -12 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(ffffffff83375fb7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b1280,ffffffff833c36e2,3b7,ffffffff833ed569) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4ce370,ffffffff8336b8fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4ce368) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff80002f404570) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c44abf0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805e281d98,1,fffffd80097fb548,ffff80002f404570) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd807a275aa8,ffff80002f404570) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd807a275aa8,ffff80002f404570) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80002f404570) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80002f404570,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002f404570,ffff80003c44af60,ffff80003c44aeb0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c44af50, count: 0 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83375fb7) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b1280,ffffffff833c36e2,3b7,ffffffff833ed569) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4ce370,ffffffff8336b8fd) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4ce368) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff80002f404570) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c44abf0) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805e281d98,1,fffffd80097fb548,ffff80002f404570) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd807a275aa8,ffff80002f404570) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd807a275aa8,ffff80002f404570) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd807a275aa8,ffff80002f404570) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80002f404570) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80002f404570,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80002f404570,ffff80003c44af60,ffff80003c44aeb0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c44af60) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c44af60) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7a2ea87a0d20, count: -16