witness: lock order reversal: 1st 0xfffffd806affc058 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd806afe43c8 inode (&ip->i_lock) lock order data w2 -> w1 missing lock order data w1 -> w2 missing Stopped at db_enter+0x18: addq $0x8,%rsp ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic the kernel did not panic ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 witness_checkorder(fffffd806afe43c8,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd806afe43c8,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd806afe43b8,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd806afe43b8,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd80653c9478,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:534 vn_lock(fffffd80653c9478,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8064bac408,8000,ffff8000256c9998,ffff8000256c9968,0,0,733ade0a6fabfb93,ffffffff81724400) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8064bac408,8000,ffff8000256c9998,ffff8000256c9968,0,0,733ade0a6fabfb93,ffffffff81724400) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256c9b00,ffff8000256c9b38,ffff8000256c9a80,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd8008596170,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256c9c90,20000180) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256c9c90) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256c9ec0) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256c9ec0) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x102e52bd460, count: -15 ddb{1}> show registers rdi 0xffff8000234a8000 rsi 0x6ce0 __ALIGN_SIZE+0x5ce0 rbp 0xffff8000256c9610 rbx 0x3 rdx 0xffff8000234a8000 rcx 0x6cdf __ALIGN_SIZE+0x5cdf rax 0xffffffff822f9b57 db_enter+0x17 r8 0xffffffff819e9edc witness_checkorder+0x10cc r9 0x5 r10 0xaf5d1ff0c54f8280 r11 0x105f1dc9021d4e93 r12 0xfffffd8002dc0900 r13 0 r14 0 r15 0 rip 0xffffffff822f9b58 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000256c9600 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=310307 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=78, nice=20 forw=0xffffffffffffffff, list=0xffff80002123afc0,0xffff80002123b270 process=0xffff8000ffff8c98 user=0xffff8000256c4000, vmspace=0xfffffd8008596170 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 41035 406339 73463 32767 7 0x10 syz-executor.0 *41035 310307 73463 32767 7 0x4000010 syz-executor.0 41035 76470 73463 32767 2 0x4000090 syz-executor.0 73463 164399 65666 32767 3 0x90 nanoslp syz-executor.0 65666 178582 82847 0 3 0x82 wait syz-executor.0 41442 188784 90610 32767 3 0x90 nanoslp syz-executor.1 90610 446911 82847 0 3 0x82 wait syz-executor.1 17852 481006 0 0 3 0x14200 bored sosplice 82847 174243 4320 0 3 0x82 thrsleep syz-fuzzer 82847 240398 4320 0 3 0x4000082 thrsleep syz-fuzzer 82847 357024 4320 0 3 0x4000082 thrsleep syz-fuzzer 82847 178559 4320 0 3 0x4000082 thrsleep syz-fuzzer 82847 237260 4320 0 3 0x4000082 thrsleep syz-fuzzer 82847 270157 4320 0 3 0x4000082 thrsleep syz-fuzzer 82847 479358 4320 0 3 0x4000082 thrsleep syz-fuzzer 82847 367401 4320 0 3 0x4000082 kqread syz-fuzzer 4320 210871 68721 0 3 0x10008a sigsusp ksh 68721 226138 71817 0 3 0x9a select sshd 26873 266173 1 0 3 0x100083 ttyin getty 71817 84137 1 0 3 0x88 select sshd 96516 33070 82037 73 3 0x100090 kqread syslogd 82037 10984 1 0 3 0x100082 netio syslogd 13949 59974 1 0 3 0x100080 kqread resolvd 85223 89386 26503 77 3 0x100092 kqread dhcpleased 2209 319672 26503 77 3 0x100092 kqread dhcpleased 26503 112975 1 0 3 0x80 kqread dhcpleased 7076 223297 0 0 3 0x14200 bored smr 84421 468833 0 0 3 0x14200 pgzero zerothread 86490 190951 0 0 3 0x14200 aiodoned aiodoned 22722 394884 0 0 3 0x14200 syncer update 11306 117560 0 0 3 0x14200 cleaner cleaner 21905 326035 0 0 3 0x14200 reaper reaper 45988 6852 0 0 3 0x14200 pgdaemon pagedaemon 4270 302440 0 0 3 0x14200 bored crynlk 37849 57014 0 0 3 0x14200 bored crypto 99741 447325 0 0 3 0x14200 bored viomb 20809 426797 0 0 3 0x40014200 acpi0 acpi0 20461 426052 0 0 3 0x40014200 idle1 67747 246315 0 0 3 0x14200 bored softnet 56565 208464 0 0 3 0x14200 bored systqmp 36272 442654 0 0 3 0x14200 bored systq 77448 474071 0 0 3 0x40014200 bored softclock 37914 281127 0 0 3 0x40014200 idle0 1 510234 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 41035 (syz-executor.0) thread 0xffff80002123a540 (310307) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8297b608) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182 #1 uvm_fault+0x224 sys/uvm/uvm_fault.c:637 #2 kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 #3 kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 #4 alltraps_kern_meltdown+0x7b #5 copyout+0x53 #6 syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] #6 syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 #7 Xsyscall+0x128 exclusive rwlock fdlock r = 0 (0xfffffd806affc058) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182 #1 sys_socketpair+0x20f #2 syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] #2 syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 #3 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10117 6407K 6433K 78643K 11231 0 pcb 13 8K 8K 78643K 13 0 rtable 116 3K 4K 78643K 565 0 ifaddr 39 10K 10K 78643K 98 0 sysctl 2 0K 0K 78643K 2 0 counters 44 34K 34K 78643K 60 0 ioctlops 0 0K 2K 78643K 482 0 iov 0 0K 12K 78643K 309 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 4 0 vnodes 1217 77K 77K 78643K 1514 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 34 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 1K 78643K 5537 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 7 21K 33K 78643K 10575 0 sigio 0 0K 0K 78643K 16 0 proc 56 74K 99K 78643K 673 0 subproc 34 2K 2K 78643K 170 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 557 0 in_multi 33 2K 2K 78643K 252 0 ether_multi 1 0K 0K 78643K 30 0 mrt 1 0K 0K 78643K 3 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 49 228K 228K 78643K 49 0 exec 0 0K 2K 78643K 1110 0 pagedep 1 8K 8K 78643K 1 0 inodedep 1 32K 32K 78643K 1 0 newblk 1 0K 0K 78643K 1 0 VM swap 7 26K 26K 78643K 7 0 UVM amap 362 57K 62K 78643K 130310 0 UVM aobj 67 7K 7K 78643K 93 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 207 0 NDP 5 0K 0K 78643K 33 0 temp 101 4209K 4305K 78643K 24681 0 kqueue 10 14K 19K 78643K 255 0 SYN cache 2 16K 16K 78643K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 22 0 0 1 0 1 1 0 8 0 rtpcb 120 250 0 247 1 0 1 1 0 8 0 rtentry 112 141 0 92 2 0 2 2 0 8 0 unpcb 120 2158 0 2139 1 0 1 1 0 8 0 syncache 296 123 0 123 11 11 0 1 0 8 0 tcpqe 32 87 0 87 7 7 0 1 0 8 0 tcpcb 736 1467 0 1463 21 20 1 6 0 8 0 arp 120 23 0 16 1 0 1 1 0 8 0 ipq 40 2 0 2 1 1 0 1 0 8 0 ipqe 40 10 0 10 1 1 0 1 0 8 0 inpcb 304 3081 0 3073 10 8 2 3 0 8 0 rttmr 72 5 0 4 1 0 1 1 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 ip6af 40 2 0 2 1 1 0 1 0 8 0 nd6 48 36 0 27 1 0 1 1 0 8 0 kcovpl 48 10 0 8 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 629 0 407 17 3 14 16 0 8 0 art_table 32 630 0 407 3 0 3 3 0 8 0 art_node 16 140 0 95 1 0 1 1 0 8 0 sysvmsgpl 40 33 0 17 1 0 1 1 0 8 0 semupl 112 5 0 5 1 1 0 1 0 8 0 semapl 112 5533 0 5523 1 0 1 1 0 8 0 shmpl 112 90 0 26 2 0 2 2 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 13244 0 11836 93 4 89 89 0 8 0 ffsino 272 13244 0 11836 94 0 94 94 0 8 0 nchpl 144 26862 0 25261 60 0 60 60 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 224 5926 0 0 349 0 349 349 0 8 0 namei 1024 61233 0 61233 1 0 1 1 0 8 1 percpumem 16 42 0 8 1 0 1 1 0 8 0 scxspl 216 78035 0 78035 13 12 1 8 0 8 1 plimitpl 152 214 0 204 1 0 1 1 0 8 0 sigapl 424 10784 0 10749 5 0 5 5 0 8 1 futexpl 56 122636 0 122636 1 0 1 1 0 8 1 knotepl 112 65 0 0 2 0 2 2 0 8 0 kqueuepl 216 14471 0 14457 9 7 2 2 0 8 1 pipepl 336 1185 0 1175 8 6 2 2 0 8 0 fdescpl 496 10767 0 10749 4 1 3 3 0 8 0 filepl 152 41897 0 41781 8 3 5 6 0 8 0 lockfpl 104 1316 0 1313 1 0 1 1 0 8 0 lockfspl 48 443 0 440 1 0 1 1 0 8 0 sessionpl 144 25 0 15 1 0 1 1 0 8 0 pgrppl 48 61 0 51 1 0 1 1 0 8 0 ucredpl 96 3007 0 2995 1 0 1 1 0 8 0 zombiepl 144 10749 0 10748 1 0 1 1 0 8 0 processpl 1072 10784 0 10748 3 0 3 3 0 8 0 procpl 672 23709 0 23664 18 14 4 5 0 8 0 sosppl 168 88 0 88 10 10 0 1 0 8 0 sockpl 480 5537 0 5508 14 10 4 7 0 8 0 mcl64k 65536 17 0 0 3 0 3 3 0 8 0 mcl16k 16384 17 0 0 3 1 2 3 0 8 0 mcl12k 12288 33 0 0 2 0 2 2 0 8 0 mcl9k 9216 9 0 0 1 0 1 1 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 25 0 0 4 1 3 3 0 8 0 mcl2k2 2112 11 0 0 1 0 1 1 0 8 0 mcl2k 2048 299 0 0 23 0 23 23 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 1048 0 0 41 0 41 41 0 8 0 bufpl 280 27184 0 20860 453 0 453 453 0 8 0 anonpl 24 2779167 0 2756966 180 39 141 149 0 186 0 amapchunkpl 152 303659 0 302682 49 10 39 44 0 158 0 amappl16 200 20404 0 19809 58 26 32 37 0 8 0 amappl15 192 97 0 91 1 0 1 1 0 8 0 amappl14 184 12 0 9 1 0 1 1 0 8 0 amappl13 176 2581 0 2580 1 0 1 1 0 8 0 amappl12 168 6 0 5 2 1 1 1 0 8 0 amappl11 160 220 0 205 1 0 1 1 0 8 0 amappl10 152 1113 0 1106 1 0 1 1 0 8 0 amappl9 144 199 0 197 1 0 1 1 0 8 0 amappl8 136 7402 0 7270 5 0 5 5 0 8 0 amappl7 128 6741 0 6728 1 0 1 1 0 8 0 amappl6 120 235 0 220 1 0 1 1 0 8 0 amappl5 112 12396 0 12377 1 0 1 1 0 8 0 amappl4 104 1150 0 1122 1 0 1 1 0 8 0 amappl3 96 769 0 752 1 0 1 1 0 8 0 amappl2 88 3225 0 3183 2 1 1 2 0 8 0 amappl1 80 183468 0 183032 12 2 10 12 0 8 0 amappl 88 127012 0 126785 6 0 6 6 0 92 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 128 253 0 253 1 1 0 1 0 8 0 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 64 92 0 26 2 0 2 2 0 8 0 uaddrrnd 24 10767 0 10749 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 10767 0 10749 1 0 1 1 0 8 0 vmmpekpl 168 54071 0 54046 2 0 2 2 0 8 0 vmmpepl 168 1245811 0 1243629 151 51 100 120 0 357 0 vmsppl 368 10766 0 10749 2 0 2 2 0 8 0 rwobjpl 56 209839 0 208393 28 7 21 21 0 8 0 pdppl 4096 21542 0 21498 75 29 46 50 0 8 2 pvpl 32 6616992 0 6591162 338 118 220 231 0 265 2 pmappl 224 10766 0 10749 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 395 0 66 10 0 10 10 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff8281cff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xb7 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x23 __mp_lock(ffffffff8297b400) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff8297b400) at __mp_lock+0x122 sys/kern/kern_lock.c:147 softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:90 Xsoftclock() at Xsoftclock+0x1f end of kernel end trace frame: 0x7f7ffffe0e80, count: -6 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x18: addq $0x8,%rsp ddb{1}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 witness_checkorder(fffffd806afe43c8,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd806afe43c8,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd806afe43b8,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd806afe43b8,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd80653c9478,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:534 vn_lock(fffffd80653c9478,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8064bac408,8000,ffff8000256c9998,ffff8000256c9968,0,0,733ade0a6fabfb93,ffffffff81724400) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8064bac408,8000,ffff8000256c9998,ffff8000256c9968,0,0,733ade0a6fabfb93,ffffffff81724400) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256c9b00,ffff8000256c9b38,ffff8000256c9a80,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd8008596170,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256c9c90,20000180) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256c9c90) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256c9ec0) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256c9ec0) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x102e52bd460, count: -15