panic: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 953 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 398430 90340 0 0x2000 0x4000000 1 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83373245) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b06e1,ffffffff833c1034,3b9,ffffffff833ea943) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003a432f10,ffffffff83366180) at refcnt_finalize+0x1db sys/kern/kern_synch.c:954 pppx_if_destroy(0,ffff80003a432f08) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80003a42f250) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003b839930) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806a182528,2,fffffd80097fb680,ffff80003a42f250) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806a21e0e8,ffff80003a42f250) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806a21e0e8,ffff80003a42f250) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806a21e0e8,ffff80003a42f250) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806a21e0e8,ffff80003a42f250) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003a42f250) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003a42f250,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003a42f250,ffff80003b839ca0,ffff80003b839bf0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 end trace frame: 0xffff80003b839c90, 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: kernel diagnostic assertion "refs != ~0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_synch.c", line 953 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83373245) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b06e1,ffffffff833c1034,3b9,ffffffff833ea943) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003a432f10,ffffffff83366180) at refcnt_finalize+0x1db sys/kern/kern_synch.c:954 pppx_if_destroy(0,ffff80003a432f08) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80003a42f250) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003b839930) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806a182528,2,fffffd80097fb680,ffff80003a42f250) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806a21e0e8,ffff80003a42f250) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806a21e0e8,ffff80003a42f250) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806a21e0e8,ffff80003a42f250) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806a21e0e8,ffff80003a42f250) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003a42f250) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003a42f250,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003a42f250,ffff80003b839ca0,ffff80003b839bf0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003b839ca0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003b839ca0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7eeb6f1b5970, count: -16 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff80003b839700 rbx 0xffffffff83828ddf cpu_info_full_primary+0x2ddf rdx 0 rcx 0xffff80003a42f250 rax 0xffffffff83827ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xa867c048235de149 r11 0xfebbc730c6b6ecc8 r12 0xffffffff83828be0 cpu_info_full_primary+0x2be0 r13 0 r14 0 r15 0x1 rip 0xffffffff82af2b05 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003b8396f0 ss 0 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=98216 pid=77760 tcnt=0 stat=onproc flags process=1008 proc=2000 runpri=32, usrpri=86, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0xffff80003a42f250 scnt=-1 ecnt=1 forw=0xffffffffffffffff, list=0xffff80003a42efb8,0xffff80003a42fa28 process=0xffff80003a4279e0 user=0xffff80003b834000, vmspace=0xfffffd806b9ac018 estcpu=36, cpticks=6, pctcpu=0.0, user=0, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 7460 286549 34197 0 2 0 syz-executor 7460 291573 34197 0 3 0x4000080 ttyopn syz-executor 90340 436137 951 0 4 0x82000 syz-executor 90340 268203 951 0 4 0x4082000 syz-executor 90340 398430 951 0 7 0x4002000 syz-executor 48083 372204 54975 0 2 0xc90 syz-executor 48083 260648 54975 0 2 0x4000010 syz-executor 48083 471868 54975 0 3 0x4000090 fsleep syz-executor 1060 191109 36557 0 2 0xc80 syz-executor 1060 208521 36557 0 3 0x4000080 rest syz-executor 1060 376589 36557 0 3 0x4000080 fsleep syz-executor 91305 493566 1 0 3 0x100083 ttyin getty 57357 107875 24886 0 2 0x10000c82 syz-executor 55594 321608 0 0 3 0x14200 bored sosplice 29650 226371 24886 0 2 0xc82 syz-executor 36557 506416 24886 0 2 0xc82 syz-executor 91995 352665 24886 0 3 0x82 wait syz-executor 34197 289060 24886 0 2 0xc82 syz-executor 3329 220697 24886 0 2 0xc82 syz-executor 951 504036 24886 0 2 0xc82 syz-executor 54975 48328 24886 0 2 0xc82 syz-executor 24886 265761 58165 0 3 0x82 kqread syz-executor 58165 284924 30930 0 3 0x10008a sigsusp ksh 30930 476416 52554 0 3 0x98 kqread sshd-session 52554 78396 82323 0 3 0x92 kqread sshd-session 82323 479685 1 0 3 0x88 kqread sshd 88445 12821 69793 74 3 0x1100092 bpf pflogd 69793 219336 1 0 3 0x80 sbwait pflogd 31348 123226 78601 73 3 0x1100090 kqread syslogd 78601 452624 1 0 3 0x100082 sbwait syslogd 8752 461265 1 0 3 0x100080 kqread resolvd 59403 282213 57615 77 3 0x100092 kqread dhcpleased 59580 63964 57615 77 3 0x100092 kqread dhcpleased 57615 93081 1 0 3 0x80 kqread dhcpleased 744 438280 0 0 3 0x14200 bored smr 27346 181017 0 0 3 0x14200 pgzero zerothread 30948 233418 0 0 3 0x14200 aiodoned aiodoned 30444 155378 0 0 3 0x14200 syncer update 25859 340076 0 0 3 0x14200 cleaner cleaner 4073 321942 0 0 3 0x14200 reaper reaper 88606 477150 0 0 3 0x14200 pgdaemon pagedaemon 74860 416996 0 0 3 0x14200 bored viomb 44413 419975 0 0 3 0x40014200 acpi0 acpi0 14134 178231 0 0 3 0x40014200 idle1 39724 27632 0 0 3 0x14200 bored softnet7 55572 147843 0 0 3 0x14200 bored softnet6 58685 492411 0 0 3 0x14200 bored softnet5 26556 373192 0 0 3 0x14200 bored softnet4 46514 500113 0 0 3 0x14200 bored softnet3 7724 135852 0 0 3 0x14200 bored softnet2 36644 331439 0 0 3 0x14200 bored softnet1 55458 478119 0 0 3 0x14200 tqbarend softnet0 22841 63762 0 0 3 0x14200 smrbar systqmp 91604 309068 0 0 3 0x14200 bored systq 52330 494938 0 0 3 0x14200 tmoslp softclockmp 12291 172461 0 0 2 0x40014200 softclock 83232 236256 0 0 3 0x40014200 idle0 1 482829 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{0}> show all locks Process 55458 (softnet0) thread 0xffff8000ffffe298 (478119) shared rwlock softnet0 r = 0 (0xffff80000002c078) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 taskq_thread+0x12a sys/kern/kern_task.c:442 #2 proc_trampoline+0x10 Process 22841 (systqmp) thread 0xffff8000ffffe000 (63762) shared rwlock systqmp r = 0 (0xffffffff837e4338) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 taskq_thread+0x12a sys/kern/kern_task.c:442 #2 proc_trampoline+0x10 ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10219 11112K 11237K 166960K 12058 0 pcb 17 12K 28K 166960K 178 0 rtable 182 7K 8K 166960K 368 0 pf 36 18K 25K 166960K 137 0 ifaddr 40 7K 8K 166960K 95 0 ifgroup 55 2K 2K 166960K 154 0 sysctl 3 1K 9K 166960K 9 0 counters 70 37K 38K 166960K 168 0 ioctlops 0 0K 4K 166960K 1719 0 iov 0 0K 16K 166960K 39 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1437 90K 91K 166960K 1935 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 6 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 24 0 dirhash 12 2K 2K 166960K 21 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 89K 166960K 770 0 sigio 0 0K 0K 166960K 18 0 proc 72 115K 163K 166960K 631 0 subproc 72 4K 4K 166960K 86 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 98 0 in_multi 88 6K 7K 166960K 160 0 ether_multi 1 0K 0K 166960K 7 0 mrt 1 0K 0K 166960K 5 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 109 493K 493K 166960K 109 0 exec 0 0K 1K 166960K 441 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 2 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 243 160K 173K 166960K 8578 0 UVM aobj 13 4K 4K 166960K 17 0 pinsyscall 42 84K 103K 166960K 1933 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 75 0 NDP 12 0K 2K 166960K 61 0 temp 61 8648K 8715K 166960K 38778 0 kqueue 14 22K 29K 166960K 145 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> 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 120 141 0 138 3 2 1 3 0 8 0 rtentry 176 126 0 50 5 0 5 5 0 8 0 unpcb 144 781 0 762 11 3 8 8 0 8 7 syncache 336 8 0 8 2 1 1 1 0 8 1 tcpqe 32 1 0 1 1 0 1 1 0 8 1 tcpcb 736 174 0 167 2 0 2 2 0 8 1 arp 128 13 0 4 1 0 1 1 0 8 0 inpcb 328 657 0 647 7 0 7 7 0 8 5 nd6 144 21 0 6 1 0 1 1 0 8 0 pkpcb 40 3 0 3 1 0 1 1 0 8 1 kcovpl 48 9 0 1 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 0 1 1 0 8 1 ppxss 1192 36 0 35 2 1 1 1 0 8 0 pppxif 1504 11 0 10 2 1 1 1 0 8 0 pfstscr 40 2 0 2 1 0 1 1 0 8 1 pffrag 232 7 0 1 1 0 1 1 0 482 0 pffrnode 88 5 0 0 1 0 1 1 0 8 0 pffrent 40 9 0 3 1 0 1 1 0 8 0 pfosfp 40 1429 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1429 0 714 21 0 21 21 0 8 0 pfanchor 1288 3 0 0 1 0 1 1 0 8 0 pfstitem 24 24 0 1 1 0 1 1 0 8 0 pfstkey 128 26 0 3 1 0 1 1 0 8 0 pfstate 384 23 0 2 3 0 3 3 0 8 0 pfrule 1344 26 0 20 2 1 1 2 0 8 0 rttmr 136 2 0 2 2 1 1 1 0 8 1 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 571 0 175 30 0 30 30 0 8 3 art_table 40 573 0 175 5 0 5 5 0 8 0 art_node 32 126 0 58 1 0 1 1 0 8 0 sysvmsgpl 40 7 0 5 1 0 1 1 0 8 0 semupl 112 1 0 1 1 0 1 1 0 8 1 semapl 112 22 0 12 1 0 1 1 0 8 0 shmpl 112 14 0 4 1 0 1 1 0 8 0 dirhash 1024 23 0 6 3 0 3 3 0 8 0 dino2pl 256 2710 0 1198 95 0 95 95 0 8 0 ffsino 296 2710 0 1198 117 0 117 117 0 8 0 nchpl 144 3868 0 2165 65 1 64 64 0 8 0 rtmask 32 5 0 5 2 1 1 1 0 8 1 uvmvnodes 80 3133 0 0 64 0 64 64 0 8 0 vnodes 216 3133 0 0 175 0 175 175 0 8 0 namei 1024 12635 0 12635 3 2 1 2 0 8 1 percpumem 16 99 0 49 1 0 1 1 0 8 0 kstatmem 264 88 0 62 4 1 3 3 0 8 1 acpiwqpl 32 2 0 2 1 0 1 1 1 8 1 scsiplug 72 4 0 4 2 1 1 1 0 8 1 scxspl 216 17166 0 17166 6 4 2 3 1 8 2 plimitpl 152 151 0 133 1 0 1 1 0 8 0 sigapl 424 1110 0 1055 9 0 9 9 0 8 1 knotepl 120 758 0 0 23 0 23 23 0 8 0 kqueuepl 224 355 0 344 7 4 3 5 0 8 2 pipepl 344 176 0 147 4 0 4 4 0 8 1 fdescpl 528 1063 0 1032 3 0 3 3 0 8 0 filepl 160 6188 0 5958 26 7 19 20 0 8 8 lockfpl 104 419 0 416 2 0 2 2 0 8 1 lockfspl 48 130 0 127 1 0 1 1 0 8 0 sessionpl 144 29 0 20 1 0 1 1 0 8 0 pgrppl 48 52 0 35 1 0 1 1 0 8 0 ucredpl 104 739 0 725 1 0 1 1 0 8 0 zombiepl 144 1059 0 1055 1 0 1 1 0 8 0 processpl 1232 1110 0 1055 6 0 6 6 0 8 1 procpl 664 2214 0 2152 8 0 8 8 0 8 2 sosppl 168 5 0 5 2 1 1 1 0 8 1 sockpl 752 1668 0 1636 33 21 12 21 0 8 8 mcl64k 65536 6 0 0 1 0 1 1 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 133 0 0 17 0 17 17 0 8 0 mcl2k 2048 25 0 0 4 0 4 4 0 8 0 mtagpl 96 8 0 0 1 0 1 1 0 8 0 mbufpl 256 395 0 0 25 0 25 25 0 8 0 bufpl 280 6509 0 366 439 0 439 439 0 8 0 anonpl 32 8263 0 0 67 0 67 67 0 246 0 amapchunkpl 152 28143 0 27647 36 7 29 29 0 158 6 amappl16 200 3364 0 3331 22 7 15 15 0 8 8 amappl15 192 15 0 15 2 2 0 1 0 8 0 amappl14 184 126 0 114 1 0 1 1 0 8 0 amappl13 176 43 0 43 1 1 0 1 0 8 0 amappl12 168 1743 0 1711 4 1 3 3 0 8 0 amappl11 160 56 0 42 1 0 1 1 0 8 0 amappl10 152 3 0 3 1 1 0 1 0 8 0 amappl9 144 271 0 270 1 0 1 1 0 8 0 amappl8 136 22 0 19 1 0 1 1 0 8 0 amappl7 128 133 0 121 1 0 1 1 0 8 0 amappl6 120 196 0 193 1 0 1 1 0 8 0 amappl5 112 148 0 139 1 0 1 1 0 8 0 amappl4 104 323 0 303 1 0 1 1 0 8 0 amappl3 96 5506 0 5392 5 1 4 4 0 8 0 amappl2 88 706 0 643 2 0 2 2 0 8 0 amappl1 80 12143 0 11551 15 1 14 15 0 8 0 amappl 88 7751 0 7582 5 0 5 5 0 92 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 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 16 0 4 1 0 1 1 0 8 0 uaddrrnd 24 1063 0 1032 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1063 0 1032 1 0 1 1 0 8 0 vmmpekpl 168 10535 0 10498 3 0 3 3 0 8 0 vmmpepl 168 73868 0 71879 105 2 103 103 0 357 11 vmsppl 488 1062 0 1032 6 1 5 5 0 8 0 rwobjpl 80 24818 0 20740 87 0 87 87 0 8 1 pdppl 4096 2134 0 2064 108 36 72 86 0 8 2 pvpl 32 18667 0 0 151 0 151 151 0 265 0 pmappl 256 1062 0 1032 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 301 0 41 8 0 8 8 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff83373245) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff833b06e1,ffffffff833c1034,3b9,ffffffff833ea943) at __assert+0x29 sys/kern/subr_prf.c:-1 refcnt_finalize(ffff80003a432f10,ffffffff83366180) at refcnt_finalize+0x1db sys/kern/kern_synch.c:954 pppx_if_destroy(0,ffff80003a432f08) at pppx_if_destroy+0x3d sys/net/if_pppx.c:794 pppxclose(205b9a,2,2000,ffff80003a42f250) at pppxclose+0xa0 sys/net/if_pppx.c:541 spec_close(ffff80003b839930) at spec_close+0x417 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd806a182528,2,fffffd80097fb680,ffff80003a42f250) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806a21e0e8,ffff80003a42f250) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806a21e0e8,ffff80003a42f250) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806a21e0e8,ffff80003a42f250) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806a21e0e8,ffff80003a42f250) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003a42f250) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003a42f250,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003a42f250,ffff80003b839ca0,ffff80003b839bf0) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff80003b839ca0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003b839ca0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7eeb6f1b5970, count: -16 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff8000299edff0) 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+0x56 kd_curproc sys/dev/kcov.c:592 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x56 sys/dev/kcov.c:153 __mp_lock(ffffffff838d3f40) at __mp_lock+0x1a3 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff838d3f40) at __mp_lock+0x1a3 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff838d3f40,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 msleep_nsec(ffff80003a424660,ffff80003a4245f8,20,ffffffff8336dc54,ffffffffffffffff) at msleep_nsec+0x132 sys/kern/kern_synch.c:219 single_thread_set(ffff8000328082b8,2) at single_thread_set+0x1de sys/kern/kern_sig.c:2336 sys_unveil(ffff8000328082b8,ffff80003c451bd0,ffff80003c451b20) at sys_unveil+0x117 sys/kern/vfs_syscalls.c:981 syscall(ffff80003c451bd0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c451bd0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xb7569a2c870, count: 3 ddb{1}> trace x86_ipi_db(ffff8000299edff0) 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+0x56 kd_curproc sys/dev/kcov.c:592 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x56 sys/dev/kcov.c:153 __mp_lock(ffffffff838d3f40) at __mp_lock+0x1a3 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff838d3f40) at __mp_lock+0x1a3 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff838d3f40,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 msleep_nsec(ffff80003a424660,ffff80003a4245f8,20,ffffffff8336dc54,ffffffffffffffff) at msleep_nsec+0x132 sys/kern/kern_synch.c:219 single_thread_set(ffff8000328082b8,2) at single_thread_set+0x1de sys/kern/kern_sig.c:2336 sys_unveil(ffff8000328082b8,ffff80003c451bd0,ffff80003c451b20) at sys_unveil+0x117 sys/kern/vfs_syscalls.c:981 syscall(ffff80003c451bd0) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80003c451bd0) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xb7569a2c870, count: -12