witness: lock order reversal: 1st 0xffffffff838bc600 &sched_lock (&sched_lock) 2nd 0xffffffff837eae30 &cq->cq_mtx (&cq->cq_mtx) lock order [1] &sched_lock (&sched_lock) -> [2] &cq->cq_mtx (&cq->cq_mtx) #0 mtx_enter+0x95 sys/kern/kern_lock.c:406 #1 clockintr_cancel+0x2f sys/kern/kern_clockintr.c:323 #2 mi_switch+0x187 sys/kern/sched_bsd.c:376 #3 ast+0x15a mi_ast sys/sys/syscall_mi.h:252 [inline] #3 ast+0x15a sys/arch/amd64/amd64/trap.c:739 #4 Xsyscall+0x156 lock order [2] &cq->cq_mtx (&cq->cq_mtx) -> [1] &sched_lock (&sched_lock) #0 mtx_enter+0x95 sys/kern/kern_lock.c:406 #1 sleep_setup+0xed sys/kern/kern_synch.c:304 #2 msleep_nsec+0x10b sys/kern/kern_synch.c:217 #3 dt_ioctl_record_stop+0xbc sys/dev/dt/dt_dev.c:589 #4 dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] #4 dtclose+0x109 sys/dev/dt/dt_dev.c:239 #5 spec_close+0x466 sys/kern/spec_vnops.c:-1 #6 VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 #7 vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] #7 vn_closefile+0x12b sys/kern/vfs_vnops.c:615 #8 fdrop+0x121 sys/kern/kern_descrip.c:1280 #9 closef+0x192 sys/kern/kern_descrip.c:1264 #10 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #10 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:775 #11 Xsyscall+0x128 Stopped at db_enter+0x25: addq $0x8,%rsp ddb{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic the kernel did not panic ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 witness_checkorder(ffffffff837eae30,9,0) at witness_checkorder+0x10d1 sys/kern/subr_witness.c:-1 mtx_enter(ffffffff837eae20) at mtx_enter+0x95 sys/kern/kern_lock.c:406 clockintr_cancel(ffffffff837ea2f8) at clockintr_cancel+0x2f sys/kern/kern_clockintr.c:323 mi_switch() at mi_switch+0x187 sys/kern/sched_bsd.c:376 ast(ffff80003c4526a0) at ast+0x15a mi_ast sys/sys/syscall_mi.h:252 [inline] ast(ffff80003c4526a0) at ast+0x15a sys/arch/amd64/amd64/trap.c:739 Xsyscall() at Xsyscall+0x156 end of kernel end trace frame: 0x3056ce7a480, count: -7 ddb{0}> show registers rdi 0 rsi 0 rbp 0xffff80003c4524a0 rbx 0 rdx 0 rcx 0xffff8000323cb248 rax 0xffffffff837e9ff0 cpu_info_full_primary+0x1ff0 r8 0xffff80003c452380 r9 0x8080808080808080 r10 0x3716d480cf28dce6 r11 0x7902646d69098dc7 r12 0xfffffd8003f4d300 r13 0xfffffd80046fa330 r14 0x3 r15 0xffffffff8341ff65 substchar+0xede0 rip 0xffffffff81f45ae5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80003c452490 ss 0x10 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=319758 pid=82764 tcnt=3 stat=run flags process=4000000 proc=4000000 runpri=50, usrpri=50, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0x0, list=0xffff8000323ca550,0xffffffff838fa8d0 process=0xffff8000fffec018 user=0xffff80003c44d000, vmspace=0xfffffd806c95a200 estcpu=6, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 82764 90529 71937 0 7 0x4000000 syz-executor 82764 217148 71937 0 2 0x4000000 syz-executor *82764 319758 71937 0 2 0x4000000 syz-executor 53428 20405 5240 0 2 0 syz-executor 5085 368939 75498 0 2 0 syz-executor 5085 466315 75498 0 2 0x4000000 syz-executor 5085 29798 75498 0 3 0x4000080 fsleep syz-executor 40543 154393 10007 0 2 0 syz-executor 40543 256331 10007 0 2 0x4000000 syz-executor 51959 223109 29355 0 2 0 syz-executor 51959 260260 29355 0 2 0x4000000 syz-executor 29174 393274 28908 0 2 0 syz-executor 29174 169495 28908 0 3 0x4000080 fsleep syz-executor 710 274874 61424 0 3 0x80 nanoslp syz-executor 710 317638 61424 0 3 0x4000080 fsleep syz-executor 710 251399 61424 0 3 0x4000080 kqpoll syz-executor 51584 169166 65389 0 2 0 syz-executor 51584 95415 65389 0 3 0x4000080 fsleep syz-executor 51584 356078 65389 0 3 0x4000080 fsleep syz-executor 51584 148456 65389 0 3 0x4000080 fsleep syz-executor 51584 307784 65389 0 3 0x4000080 fsleep syz-executor 51584 370676 65389 0 3 0x4000080 fsleep syz-executor 61424 176394 91625 0 2 0x2 syz-executor 5240 319268 91625 0 3 0x82 nanoslp syz-executor 75498 184460 91625 0 3 0x82 nanoslp syz-executor 10007 520219 91625 0 3 0x82 nanoslp syz-executor 71937 500759 91625 0 3 0x82 nanoslp syz-executor 28908 95146 91625 0 3 0x82 nanoslp syz-executor 29355 37807 91625 0 3 0x82 nanoslp syz-executor 65389 81588 91625 0 3 0x82 nanoslp syz-executor 91625 241043 65746 0 3 0x82 kqread syz-executor 65746 90980 60018 0 3 0x10008a sigsusp ksh 60018 471379 43859 0 3 0x98 kqread sshd-session 43859 25978 52447 0 3 0x92 kqread sshd-session 87420 136127 1 0 3 0x100083 ttyopn getty 52447 520117 1 0 3 0x88 kqread sshd 66151 306606 46993 74 3 0x1100092 bpf pflogd 46993 497129 1 0 3 0x80 sbwait pflogd 54411 502945 71707 73 3 0x1100090 kqread syslogd 71707 77316 1 0 3 0x100082 sbwait syslogd 52286 254866 1 0 3 0x100080 kqread resolvd 4513 324785 56015 77 3 0x100092 kqread dhcpleased 75994 428006 56015 77 3 0x100092 kqread dhcpleased 56015 150979 1 0 3 0x80 kqread dhcpleased 91615 92970 0 0 3 0x14200 bored smr 6537 353705 0 0 2 0x14200 zerothread 73975 103908 0 0 3 0x14200 aiodoned aiodoned 40505 246739 0 0 3 0x14200 syncer update 52276 421671 0 0 3 0x14200 cleaner cleaner 63882 14501 0 0 3 0x14200 reaper reaper 49585 219463 0 0 3 0x14200 pgdaemon pagedaemon 54042 288494 0 0 3 0x14200 bored viomb 15912 287152 0 0 3 0x40014200 acpi0 acpi0 1967 496828 0 0 3 0x40014200 idle1 51402 90227 0 0 3 0x14200 bored softnet1 6777 191196 0 0 3 0x14200 bored softnet0 11088 301012 0 0 3 0x14200 smrbar systqmp 38295 438686 0 0 3 0x14200 bored systq 23257 161524 0 0 3 0x14200 tmoslp softclockmp 62293 217595 0 0 3 0x40014200 tmoslp softclock 22540 4784 0 0 3 0x40014200 idle0 1 499435 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &sched_lock r = 0 (0xffffffff838bc600) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 mtx_enter+0x4b4 sys/kern/kern_lock.c:487 #2 preempt+0x35 sys/kern/sched_bsd.c:338 #3 ast+0x15a mi_ast sys/sys/syscall_mi.h:252 [inline] #3 ast+0x15a sys/arch/amd64/amd64/trap.c:739 #4 Xsyscall+0x156 Process 11088 (systqmp) thread 0xffff8000ffffe530 (301012) shared rwlock systqmp r = 0 (0xffffffff8387adb8) #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 11063 12279K 12427K 166960K 12194 0 pcb 17 12K 12K 166960K 33 0 rtable 223 6K 6K 166960K 358 0 pf 34 17K 18K 166960K 38 0 ifaddr 41 7K 7K 166960K 45 0 ifgroup 55 2K 2K 166960K 55 0 sysctl 1 1K 9K 166960K 5 0 counters 70 37K 37K 166960K 70 0 ioctlops 0 0K 4K 166960K 1466 0 iov 0 0K 12K 166960K 2 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1342 84K 85K 166960K 1390 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 1K 166960K 2 0 VM map 2 1K 1K 166960K 2 0 sem 4 0K 0K 166960K 4 0 dirhash 12 2K 2K 166960K 12 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 89K 166960K 172 0 proc 71 115K 164K 166960K 538 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 2 0 in_multi 89 6K 6K 166960K 99 0 ether_multi 1 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 43 201K 201K 166960K 43 0 exec 0 0K 1K 166960K 387 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 253 159K 168K 166960K 3500 0 UVM aobj 4 2K 2K 166960K 4 0 pinsyscall 43 86K 104K 166960K 1326 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 26 1K 1K 166960K 28 0 temp 37 8666K 8731K 166960K 4264 0 kqueue 14 22K 27K 166960K 36 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 38 0 35 1 0 1 1 0 8 0 rtentry 176 111 0 8 5 0 5 5 0 8 0 unpcb 144 51 0 30 2 0 2 2 0 8 1 syncache 336 3 0 3 1 0 1 1 0 8 1 tcpcb 736 12 0 7 1 0 1 1 0 8 0 arp 136 18 0 0 1 0 1 1 0 8 0 inpcb 328 98 0 90 2 0 2 2 0 8 1 nd6 152 24 0 3 1 0 1 1 0 8 0 pkpcb 40 1 0 1 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 pffrag 232 1 0 0 1 0 1 1 0 482 0 pffrnode 88 1 0 0 1 0 1 1 0 8 0 pffrent 40 1 0 0 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 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 452 0 40 28 0 28 28 0 8 0 art_table 40 453 0 40 5 0 5 5 0 8 0 art_node 32 111 0 10 1 0 1 1 0 8 0 semapl 112 2 0 0 1 0 1 1 0 8 0 shmpl 112 1 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1630 0 117 95 0 95 95 0 8 0 ffsino 296 1630 0 117 117 0 117 117 0 8 0 nchpl 144 1870 0 169 64 0 64 64 0 8 0 vnodes 216 1730 0 0 97 0 97 97 0 8 0 namei 1024 5679 0 5679 2 0 2 2 0 8 2 percpumem 16 50 0 0 1 0 1 1 0 8 0 kstatmem 264 26 0 0 2 0 2 2 0 8 0 scsiplug 72 3 0 3 1 0 1 1 0 8 1 scxspl 216 6434 0 6434 3 1 2 2 1 8 2 plimitpl 152 31 0 13 1 0 1 1 0 8 0 sigapl 424 489 0 441 7 0 7 7 0 8 1 knotepl 120 62 0 0 2 0 2 2 0 8 0 kqueuepl 224 41 0 29 2 0 2 2 0 8 1 pipepl 344 123 0 95 3 0 3 3 0 8 0 fdescpl 528 473 0 441 3 0 3 3 0 8 0 filepl 160 1743 0 1520 10 0 10 10 0 8 0 lockfpl 104 21 0 17 1 0 1 1 0 8 0 lockfspl 48 12 0 8 1 0 1 1 0 8 0 sessionpl 144 22 0 13 1 0 1 1 0 8 0 pgrppl 48 30 0 13 1 0 1 1 0 8 0 ucredpl 104 116 0 103 1 0 1 1 0 8 0 zombiepl 144 441 0 441 1 0 1 1 0 8 1 processpl 1232 489 0 441 5 0 5 5 0 8 1 procpl 664 563 0 501 6 0 6 6 0 8 0 sockpl 752 190 0 158 5 0 5 5 0 8 1 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 113 0 0 15 0 15 15 0 8 0 mcl2k 2048 25 0 0 4 0 4 4 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 140 0 0 9 0 9 9 0 8 0 bufpl 280 2562 0 131 174 0 174 174 0 8 0 anonpl 32 4472 0 0 37 0 37 37 0 246 0 amapchunkpl 152 9612 0 9085 22 0 22 22 0 158 1 amappl16 200 1813 0 1745 5 0 5 5 0 8 0 amappl15 192 98 0 98 1 0 1 1 0 8 1 amappl14 184 6 0 6 1 0 1 1 0 8 1 amappl13 176 447 0 446 1 0 1 1 0 8 0 amappl12 168 841 0 798 3 0 3 3 0 8 0 amappl11 160 3 0 3 1 0 1 1 0 8 1 amappl10 152 48 0 34 1 0 1 1 0 8 0 amappl9 144 247 0 247 1 0 1 1 0 8 1 amappl8 136 36 0 33 1 0 1 1 0 8 0 amappl7 128 82 0 81 1 0 1 1 0 8 0 amappl6 120 281 0 267 1 0 1 1 0 8 0 amappl5 112 82 0 72 1 0 1 1 0 8 0 amappl4 104 423 0 394 1 0 1 1 0 8 0 amappl3 96 1500 0 1399 4 1 3 3 0 8 0 amappl2 88 582 0 506 2 0 2 2 0 8 0 amappl1 80 9236 0 8637 15 0 15 15 0 8 1 amappl 88 2750 0 2575 5 0 5 5 0 92 0 uvmvnodes 80 99 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 3 0 0 1 0 1 1 0 8 0 uaddrrnd 24 473 0 441 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 473 0 441 1 0 1 1 0 8 0 vmmpekpl 168 5693 0 5659 2 0 2 2 0 8 0 vmmpepl 168 38051 0 36035 89 0 89 89 0 357 1 vmsppl 488 472 0 441 5 0 5 5 0 8 0 rwobjpl 80 13798 0 12717 24 0 24 24 0 8 1 pdppl 4096 954 0 882 100 16 84 84 0 8 12 pvpl 32 11931 0 0 97 0 97 97 0 265 0 pmappl 256 472 0 441 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 266 0 18 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 witness_checkorder(ffffffff837eae30,9,0) at witness_checkorder+0x10d1 sys/kern/subr_witness.c:-1 mtx_enter(ffffffff837eae20) at mtx_enter+0x95 sys/kern/kern_lock.c:406 clockintr_cancel(ffffffff837ea2f8) at clockintr_cancel+0x2f sys/kern/kern_clockintr.c:323 mi_switch() at mi_switch+0x187 sys/kern/sched_bsd.c:376 ast(ffff80003c4526a0) at ast+0x15a mi_ast sys/sys/syscall_mi.h:252 [inline] ast(ffff80003c4526a0) at ast+0x15a sys/arch/amd64/amd64/trap.c:739 Xsyscall() at Xsyscall+0x156 end of kernel end trace frame: 0x3056ce7a480, count: -7 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp ddb{1}> trace x86_ipi_db(ffff8000299ddff0) 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 mtx_enter(ffffffff838bc5f0) at mtx_enter+0x377 sys/kern/kern_lock.c:454 schedclock(ffff8000323cad18) at schedclock+0xac sys/kern/sched_bsd.c:542 statclock(ffff8000299dee08,ffff80003c4222a0,0) at statclock+0x3f6 sys/kern/kern_clock.c:-1 clockintr_dispatch(ffff80003c4222a0) at clockintr_dispatch+0x3f0 sys/kern/kern_clockintr.c:-1 lapic_clockintr(0,0) at lapic_clockintr+0x51 sys/arch/amd64/amd64/lapic.c:482 Xresume_lapic_ltimer() at Xresume_lapic_ltimer+0x2a end of kernel end trace frame: 0x7ba04e724c60, count: -9