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 168327 13829 0 0x2 0 0 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83467140) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83415f82,ffffffff8341819b,3b7,ffffffff8341821e) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4f34f8,ffffffff8335d4c5) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4f34f0) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff800035be2560) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4f9410) at spec_close+0x412 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805ea126d0,1,fffffd80097fb680,ffff800035be2560) at VOP_CLOSE+0x133 sys/kern/vfs_vops.c:156 vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd80623bac88,ffff800035be2560) at fdrop+0x126 sys/kern/kern_descrip.c:1267 closef(fffffd80623bac88,ffff800035be2560) at closef+0x192 sys/kern/kern_descrip.c:1251 fdfree(ffff800035be2560) at fdfree+0x116 sys/kern/kern_descrip.c:1182 exit1(ffff800035be2560,0,0,1) at exit1+0x59c sys/kern/kern_exit.c:215 sys_exit(ffff800035be2560,ffff80003c4f9780,ffff80003c4f96d0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c4f9770, 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(ffffffff83467140) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83415f82,ffffffff8341819b,3b7,ffffffff8341821e) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4f34f8,ffffffff8335d4c5) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4f34f0) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff800035be2560) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4f9410) at spec_close+0x412 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805ea126d0,1,fffffd80097fb680,ffff800035be2560) at VOP_CLOSE+0x133 sys/kern/vfs_vops.c:156 vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd80623bac88,ffff800035be2560) at fdrop+0x126 sys/kern/kern_descrip.c:1267 closef(fffffd80623bac88,ffff800035be2560) at closef+0x192 sys/kern/kern_descrip.c:1251 fdfree(ffff800035be2560) at fdfree+0x116 sys/kern/kern_descrip.c:1182 exit1(ffff800035be2560,0,0,1) at exit1+0x59c sys/kern/kern_exit.c:215 sys_exit(ffff800035be2560,ffff80003c4f9780,ffff80003c4f96d0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c4f9780) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c4f9780) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7cae39151bd0, count: -16 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80003c4f91e0 rbx 0xffff8000299dedd7 rdx 0 rcx 0xffff800035be2560 rax 0xffff8000299ddff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x5f78a8776a5df6e9 r11 0xcb88a971a48ff12e r12 0xffff8000299debd8 r13 0 r14 0 r15 0x1 rip 0xffffffff814a5eb5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c4f91d0 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=176100 pid=33481 tcnt=0 stat=onproc flags process=1008 proc=2000 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0xffff800035be2560 scnt=-1 ecnt=1 forw=0xffffffffffffffff, list=0xffff800035be2040,0xffff800035be42d8 process=0xffff80003c495d38 user=0xffff80003c4f4000, vmspace=0xfffffd806225b3e8 estcpu=36, cpticks=3, pctcpu=0.0, user=0, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 78126 60884 45156 0 2 0 syz-executor 78126 350518 45156 0 2 0x4000000 syz-executor 78126 75849 45156 0 3 0x4000080 fsleep syz-executor 33957 383213 80699 0 2 0 syz-executor 33957 153714 80699 0 3 0x4000080 kqsel syz-executor 33957 163823 80699 0 3 0x4000080 kqread syz-executor 23452 486349 34883 0 3 0x80 nanoslp syz-executor 23452 27766 34883 0 3 0x4000080 kqpoll syz-executor 23452 149133 34883 0 3 0x4000080 fsleep syz-executor 79940 32965 85420 0 2 0 syz-executor 79940 61065 85420 0 2 0x4000000 syz-executor 22186 52433 91828 0 3 0x80 nanoslp syz-executor 22186 493354 91828 0 3 0x4000080 kqpoll syz-executor 22186 130242 91828 0 3 0x4000080 fsleep syz-executor 61984 391278 83063 0 2 0 syz-executor 61984 14469 83063 0 3 0x4000080 kqsel syz-executor 13829 168327 93499 0 7 0x2 syz-executor 12919 160940 1 0 3 0x80 nanoslp init 34883 388712 93499 0 3 0x82 nanoslp syz-executor 93043 183939 93499 0 3 0x82 nanoslp syz-executor 94182 394136 0 0 3 0x14200 bored sosplice 85326 596 0 0 3 0x14280 nfsidl nfsio 47987 523911 0 0 3 0x14280 nfsidl nfsio 20375 286284 0 0 3 0x14280 nfsidl nfsio 78771 310626 0 0 3 0x14280 nfsidl nfsio 60615 216981 0 0 3 0x14280 nfsidl nfsio 18178 122011 0 0 3 0x14280 nfsidl nfsio 70882 129911 0 0 3 0x14280 nfsidl nfsio 88904 421547 0 0 3 0x14280 nfsidl nfsio 62239 300283 0 0 3 0x14280 nfsidl nfsio 36416 176923 0 0 3 0x14280 nfsidl nfsio 37438 105547 0 0 3 0x14280 nfsidl nfsio 91179 385549 0 0 3 0x14280 nfsidl nfsio 17555 362216 0 0 3 0x14280 nfsidl nfsio 54099 150787 0 0 3 0x14280 nfsidl nfsio 15588 194873 0 0 3 0x14280 nfsidl nfsio 1865 367875 0 0 3 0x14280 nfsidl nfsio 73830 81432 0 0 3 0x14280 nfsidl nfsio 75370 354741 0 0 3 0x14280 nfsidl nfsio 79731 286883 0 0 3 0x14280 nfsidl nfsio 52887 448319 0 0 3 0x14280 nfsidl nfsio 83063 75118 93499 0 3 0x82 nanoslp syz-executor 80699 46684 93499 0 3 0x82 nanoslp syz-executor 91828 366302 93499 0 3 0x82 nanoslp syz-executor 45156 57453 93499 0 3 0x82 nanoslp syz-executor 85420 445667 93499 0 3 0x82 nanoslp syz-executor 93499 144382 71983 0 3 0x82 kqread syz-executor 71983 368245 5798 0 3 0x10008a sigsusp ksh 5798 357023 4715 0 3 0x98 kqread sshd-session 4715 278009 99638 0 3 0x92 kqread sshd-session 99638 103660 1 0 3 0x88 kqread sshd 55024 275815 6107 74 3 0x1100092 bpf pflogd 6107 434236 1 0 3 0x80 sbwait pflogd 50607 93058 19597 73 3 0x1100090 kqread syslogd 19597 201936 1 0 3 0x100082 sbwait syslogd 88001 46273 1 0 3 0x100080 kqread resolvd 29379 16329 75285 77 3 0x100092 kqread dhcpleased 38234 499748 75285 77 2 0x100012 dhcpleased 75285 17539 1 0 3 0x80 kqread dhcpleased 36072 226802 0 0 3 0x14200 bored smr 46805 423324 0 0 2 0x14200 zerothread 67828 90468 0 0 3 0x14200 aiodoned aiodoned 33680 503039 0 0 3 0x14200 syncer update 46430 502189 0 0 3 0x14200 cleaner cleaner 78452 318791 0 0 3 0x14200 reaper reaper 91719 364075 0 0 3 0x14200 pgdaemon pagedaemon 54387 290721 0 0 3 0x14200 bored viomb 64927 332090 0 0 3 0x40014200 acpi0 acpi0 28527 256056 0 0 3 0x40014200 idle1 85225 242531 0 0 3 0x14200 bored softnet3 81578 91853 0 0 3 0x14200 bored softnet2 10343 365429 0 0 3 0x14200 bored softnet1 90455 478032 0 0 2 0x14200 softnet0 89239 49127 0 0 3 0x14200 bored systqmp 65186 344630 0 0 3 0x14200 bored systq 2909 129847 0 0 3 0x14200 tmoslp softclockmp 43238 268891 0 0 3 0x40014200 tmoslp softclock 73978 213468 0 0 3 0x40014200 idle0 1 193435 0 0 3 0x80082 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 78126 (syz-executor) thread 0xffff800035be4038 (350518) exclusive rrwlock inode r = 0 (0xfffffd806e053d10) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x377 sys/kern/kern_rwlock.c:310 #2 rrw_enter+0xc6 sys/kern/kern_rwlock.c:605 #3 VOP_LOCK+0xa6 sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x190 sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x23c sys/kern/sys_generic.c:380 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:742 #9 Xsyscall+0x128 Process 90455 (softnet0) thread 0xffff8000ffffe520 (478032) shared rwlock softnet0 r = 0 (0xffff80000002c078) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 taskq_thread+0x12a sys/kern/kern_task.c:442 #2 proc_trampoline+0x10 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10238 11118K 11825K 166960K 14609 0 pcb 18 16K 19K 166960K 336 0 rtable 251 11K 12K 166960K 692 0 pf 41 18K 82K 166960K 179 0 ifaddr 43 7K 8K 166960K 119 0 ifgroup 65 2K 3K 166960K 205 0 sysctl 4 1K 9K 166960K 19 0 counters 78 37K 38K 166960K 222 0 ioctlops 0 0K 4K 166960K 1989 0 iov 0 0K 28K 166960K 128 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1590 100K 100K 166960K 3316 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 26 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 202 0 dirhash 12 2K 2K 166960K 42 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 110K 166960K 1812 0 sigio 1 0K 0K 166960K 36 0 proc 64 79K 128K 166960K 837 0 subproc 72 4K 4K 166960K 100 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 1 0K 0K 166960K 319 0 in_multi 88 6K 7K 166960K 196 0 ether_multi 1 0K 0K 166960K 15 0 mrt 2 0K 0K 166960K 17 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 91 413K 413K 166960K 91 0 exec 0 0K 1K 166960K 845 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 3 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 251 164K 181K 166960K 18400 0 UVM aobj 46 4K 4K 166960K 51 0 pinsyscall 41 82K 104K 166960K 2994 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 1K 166960K 110 0 NDP 15 0K 2K 166960K 80 0 temp 79 8692K 8820K 166960K 87056 0 kqueue 17 28K 33K 166960K 391 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 120 200 0 197 3 0 3 3 0 8 2 rtentry 176 199 0 100 6 0 6 6 0 8 0 unpcb 144 1185 0 1164 6 4 2 4 0 8 1 syncache 336 10 0 10 4 3 1 1 0 8 1 tcpqe 32 2 0 2 1 1 0 1 0 8 0 tcpcb 736 691 0 683 14 10 4 7 0 8 3 arp 128 34 0 15 1 0 1 1 0 8 0 inpcb 328 2149 0 2128 21 17 4 12 0 8 2 nd6 144 40 0 19 2 0 2 2 0 8 0 pkpcb 40 10 0 10 4 3 1 1 0 8 1 kcovpl 48 11 0 3 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 1 0 1 0 8 0 ppxss 1192 54 0 51 3 2 1 1 0 8 0 pppxif 1504 11 0 10 3 2 1 1 0 8 0 pffrag 232 13 0 3 1 0 1 1 0 482 0 pffrnode 88 13 0 3 1 0 1 1 0 8 0 pffrent 40 22 0 12 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 pfrktable 1344 1 0 1 1 1 0 1 0 8 0 pftag 88 2 0 0 1 0 1 1 0 8 0 pfqueue 320 1 0 1 1 1 0 1 0 8 0 pfstitem 24 125 0 31 1 0 1 1 0 8 0 pfstkey 128 125 0 31 4 0 4 4 0 8 0 pfstate 384 125 0 31 10 0 10 10 0 8 0 pfrule 1344 25 0 19 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 256 791 0 380 32 3 29 31 0 8 0 art_table 32 795 0 380 5 1 4 5 0 8 0 art_node 16 196 0 110 1 0 1 1 0 8 0 sysvmsgpl 40 28 0 26 1 0 1 1 0 8 0 semapl 112 196 0 186 1 0 1 1 0 8 0 shmpl 112 48 0 5 2 0 2 2 0 8 0 dirhash 1024 37 0 20 3 0 3 3 0 8 0 dino2pl 256 4641 0 3131 95 0 95 95 0 8 0 ffsino 288 4641 0 3131 109 0 109 109 0 8 0 nchpl 144 7180 0 5472 64 0 64 64 0 8 0 rtmask 32 12 0 11 5 4 1 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 28136 0 28136 3 2 1 2 0 8 1 percpumem 16 126 0 72 1 0 1 1 0 8 0 kstatmem 264 122 0 86 3 0 3 3 0 8 0 scsiplug 72 9 0 9 4 3 1 1 0 8 1 scxspl 216 51033 0 51033 12 9 3 6 1 8 3 plimitpl 152 353 0 334 1 0 1 1 0 8 0 sigapl 424 2128 0 2058 10 1 9 9 0 8 0 knotepl 120 571 0 0 17 0 17 17 0 8 0 kqueuepl 224 681 0 663 6 4 2 5 0 8 0 pipepl 336 475 0 448 11 5 6 8 0 8 3 fdescpl 520 2087 0 2056 3 0 3 3 0 8 0 filepl 160 15871 0 15638 29 15 14 21 0 8 1 lockfpl 104 954 0 951 3 2 1 2 0 8 0 lockfspl 48 439 0 436 1 0 1 1 0 8 0 sessionpl 144 32 0 24 1 0 1 1 0 8 0 pgrppl 48 93 0 77 1 0 1 1 0 8 0 ucredpl 104 2672 0 2658 1 0 1 1 0 8 0 zombiepl 144 2059 0 2058 1 0 1 1 0 8 0 processpl 1240 2128 0 2058 6 0 6 6 0 8 0 procpl 656 4924 0 4844 9 1 8 8 0 8 0 srpgc 96 14 0 14 3 2 1 1 0 8 1 sosppl 168 5 0 5 2 1 1 1 0 8 1 sockpl 728 3603 0 3557 33 21 12 16 0 8 7 mcl64k 65536 5 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 116 0 0 15 0 15 15 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 48 0 0 5 0 5 5 0 8 0 mtagpl 96 31 0 0 1 0 1 1 0 8 0 mbufpl 256 395 0 0 23 0 23 23 0 8 0 bufpl 280 22239 0 16097 440 0 440 440 0 8 0 anonpl 32 15358 0 0 124 0 124 124 0 246 0 amapchunkpl 152 61334 0 60787 38 12 26 30 0 158 3 amappl16 200 8381 0 8338 70 55 15 36 0 8 5 amappl15 192 38 0 38 2 2 0 1 0 8 0 amappl14 184 127 0 116 1 0 1 1 0 8 0 amappl13 176 22 0 21 1 0 1 1 0 8 0 amappl12 168 2826 0 2796 2 0 2 2 0 8 0 amappl11 160 54 0 40 1 0 1 1 0 8 0 amappl10 152 3 0 3 1 1 0 1 0 8 0 amappl9 144 249 0 249 1 1 0 1 0 8 0 amappl8 136 27 0 24 1 0 1 1 0 8 0 amappl7 128 117 0 106 1 0 1 1 0 8 0 amappl6 120 213 0 210 1 0 1 1 0 8 0 amappl5 112 139 0 127 1 0 1 1 0 8 0 amappl4 104 368 0 349 1 0 1 1 0 8 0 amappl3 96 12456 0 12337 5 1 4 4 0 8 0 amappl2 88 719 0 656 2 0 2 2 0 8 0 amappl1 80 16075 0 15491 17 2 15 15 0 8 0 amappl 88 17317 0 17137 5 0 5 5 0 92 0 dma4096 4096 2 0 2 2 2 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 7 0 7 2 2 0 1 0 8 0 dma128 128 258 0 258 4 3 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 20 0 19 1 0 1 1 0 8 0 aobjpl 72 50 0 5 1 0 1 1 0 8 0 uaddrrnd 24 2087 0 2056 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2087 0 2056 1 0 1 1 0 8 0 vmmpekpl 168 18088 0 18033 3 0 3 3 0 8 0 vmmpepl 168 136630 0 134609 121 20 101 118 0 357 1 vmsppl 480 2086 0 2056 7 2 5 5 0 8 0 rwobjpl 72 43161 0 36259 128 0 128 128 0 8 0 pdppl 4096 4181 0 4112 109 38 71 83 0 8 2 pvpl 32 23347 0 0 189 0 189 189 0 265 0 pmappl 256 2086 0 2056 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 439 0 66 11 0 11 11 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff838c4ff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c kd_curproc sys/dev/kcov.c:584 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c sys/dev/kcov.c:153 __mp_lock(ffffffff8395f138) at __mp_lock+0x1a3 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8395f138) at __mp_lock+0x1a3 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x12a sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8395f138) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8395f138) at __mp_lock+0x199 sys/kern/kern_lock.c:165 dofstatat(ffff800035be2d10,ffffff9c,7826f123b860,7826f123bc60,2) at dofstatat+0xcf sys/kern/vfs_syscalls.c:2082 syscall(ffff80002a364070) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a364070) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7826f123bd10, count: 3 ddb{0}> trace x86_ipi_db(ffffffff838c4ff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c kd_curproc sys/dev/kcov.c:584 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c sys/dev/kcov.c:153 __mp_lock(ffffffff8395f138) at __mp_lock+0x1a3 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8395f138) at __mp_lock+0x1a3 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x12a sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8395f138) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8395f138) at __mp_lock+0x199 sys/kern/kern_lock.c:165 dofstatat(ffff800035be2d10,ffffff9c,7826f123b860,7826f123bc60,2) at dofstatat+0xcf sys/kern/vfs_syscalls.c:2082 syscall(ffff80002a364070) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a364070) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7826f123bd10, 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(ffffffff83467140) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83415f82,ffffffff8341819b,3b7,ffffffff8341821e) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4f34f8,ffffffff8335d4c5) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4f34f0) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff800035be2560) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4f9410) at spec_close+0x412 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805ea126d0,1,fffffd80097fb680,ffff800035be2560) at VOP_CLOSE+0x133 sys/kern/vfs_vops.c:156 vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd80623bac88,ffff800035be2560) at fdrop+0x126 sys/kern/kern_descrip.c:1267 closef(fffffd80623bac88,ffff800035be2560) at closef+0x192 sys/kern/kern_descrip.c:1251 fdfree(ffff800035be2560) at fdfree+0x116 sys/kern/kern_descrip.c:1182 exit1(ffff800035be2560,0,0,1) at exit1+0x59c sys/kern/kern_exit.c:215 sys_exit(ffff800035be2560,ffff80003c4f9780,ffff80003c4f96d0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003c4f9770, count: 0 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83467140) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83415f82,ffffffff8341819b,3b7,ffffffff8341821e) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003c4f34f8,ffffffff8335d4c5) at refcnt_finalize+0x1db sys/kern/kern_synch.c:952 pppx_if_destroy(0,ffff80003c4f34f0) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,1,2000,ffff800035be2560) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003c4f9410) at spec_close+0x412 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805ea126d0,1,fffffd80097fb680,ffff800035be2560) at VOP_CLOSE+0x133 sys/kern/vfs_vops.c:156 vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd80623bac88,ffff800035be2560) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd80623bac88,ffff800035be2560) at fdrop+0x126 sys/kern/kern_descrip.c:1267 closef(fffffd80623bac88,ffff800035be2560) at closef+0x192 sys/kern/kern_descrip.c:1251 fdfree(ffff800035be2560) at fdfree+0x116 sys/kern/kern_descrip.c:1182 exit1(ffff800035be2560,0,0,1) at exit1+0x59c sys/kern/kern_exit.c:215 sys_exit(ffff800035be2560,ffff80003c4f9780,ffff80003c4f96d0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003c4f9780) at syscall+0xb08 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c4f9780) at syscall+0xb08 sys/arch/amd64/amd64/trap.c:742 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7cae39151bd0, count: -16