witness: lock order reversal: 1st 0xfffffd807503f250 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd805e8740a0 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{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+0x18 sys/arch/amd64/amd64/db_interface.c:440 witness_checkorder(fffffd805e8740a0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd805e8740a0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd805e874090,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd805e874090,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd8062434168,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd8062434168,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd80593c0180,0,ffff8000256bb928,ffff8000256bb8f8,0,0,85903dcd0f155d5b,ffffffff821a9380) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd80593c0180,0,ffff8000256bb928,ffff8000256bb8f8,0,0,85903dcd0f155d5b,ffffffff821a9380) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256bba90,ffff8000256bbac8,ffff8000256bba10,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd806f0d32e8,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256bbc20,20000140) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256bbc20) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256bbe50) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256bbe50) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xe4f43eaeba0, count: -15 ddb{0}> show registers rdi 0xffff800021282000 rsi 0x5c60 __ALIGN_SIZE+0x4c60 rbp 0xffff8000256bb5a0 rbx 0x3 rdx 0xffff800021282000 rcx 0x5c5f __ALIGN_SIZE+0x4c5f rax 0xffffffff8173a2b7 db_enter+0x17 r8 0xffffffff814a128c witness_checkorder+0x10cc r9 0x5 r10 0x763b4061b4b90f51 r11 0xd0892b119f3b9573 r12 0xfffffd8002dbf880 r13 0 r14 0 r15 0 rip 0xffffffff8173a2b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000256bb590 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor.0) pid=214022 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=78, nice=20 forw=0xffffffffffffffff, list=0xffff8000212117a0,0xffffffff82850db0 process=0xffff8000ffff8868 user=0xffff8000256b6000, vmspace=0xfffffd806f0d32e8 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 67313 78046 91700 32767 7 0x10 syz-executor.0 *67313 214022 91700 32767 7 0x4000010 syz-executor.0 33797 138852 83425 32767 2 0x10 syz-executor.1 33797 93075 83425 32767 2 0x4000010 syz-executor.1 83425 101126 87809 32767 3 0x90 nanoslp syz-executor.1 87809 151417 32914 0 3 0x82 wait syz-executor.1 91700 3281 86606 32767 3 0x90 nanoslp syz-executor.0 86606 396105 32914 0 3 0x82 wait syz-executor.0 32914 112210 20220 0 3 0x82 thrsleep syz-fuzzer 32914 85649 20220 0 3 0x4000082 thrsleep syz-fuzzer 32914 370328 20220 0 3 0x4000082 kqread syz-fuzzer 32914 340145 20220 0 3 0x4000082 thrsleep syz-fuzzer 32914 388318 20220 0 3 0x4000082 thrsleep syz-fuzzer 32914 21708 20220 0 3 0x4000082 thrsleep syz-fuzzer 32914 30972 20220 0 3 0x4000082 thrsleep syz-fuzzer 32914 452778 20220 0 3 0x4000082 thrsleep syz-fuzzer 20220 217781 17191 0 3 0x10008a sigsusp ksh 17191 451632 43802 0 3 0x9a select sshd 44795 401406 1 0 3 0x100083 ttyin getty 43802 190239 1 0 3 0x88 select sshd 62074 54560 25078 73 3 0x100090 kqread syslogd 25078 311630 1 0 3 0x100082 netio syslogd 72951 496854 1 0 3 0x100080 kqread resolvd 70387 481068 96684 77 3 0x100092 kqread dhcpleased 76705 153661 96684 77 3 0x100092 kqread dhcpleased 96684 499104 1 0 3 0x80 kqread dhcpleased 88423 476810 0 0 3 0x14200 bored smr 68884 421402 0 0 2 0x14200 zerothread 77452 494539 0 0 3 0x14200 aiodoned aiodoned 53155 305589 0 0 3 0x14200 syncer update 44855 71056 0 0 3 0x14200 cleaner cleaner 98023 282687 0 0 3 0x14200 reaper reaper 1125 294080 0 0 3 0x14200 pgdaemon pagedaemon 53910 240403 0 0 3 0x14200 bored crynlk 72574 5584 0 0 3 0x14200 bored crypto 1371 261627 0 0 3 0x14200 bored viomb 57098 314985 0 0 3 0x40014200 acpi0 acpi0 79726 345141 0 0 3 0x40014200 idle1 16156 301397 0 0 3 0x14200 bored softnet 97741 396036 0 0 3 0x14200 bored systqmp 55035 133886 0 0 3 0x14200 bored systq 69928 520601 0 0 3 0x40014200 bored softclock 68852 100966 0 0 3 0x40014200 idle0 1 133477 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 67313 (syz-executor.0) thread 0xffff8000212102a0 (214022) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff829e9558) #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 (0xfffffd807503f250) #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{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10113 6407K 6433K 78643K 11203 0 pcb 13 8K 8K 78643K 13 0 rtable 106 3K 3K 78643K 168 0 ifaddr 39 10K 10K 78643K 39 0 counters 44 34K 34K 78643K 44 0 ioctlops 0 0K 2K 78643K 27 0 iov 0 0K 0K 78643K 1 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 6 0 vnodes 1216 76K 76K 78643K 1221 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 1K 78643K 2 0 VM map 2 1K 1K 78643K 2 0 sem 9 0K 1K 78643K 76 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 8 25K 33K 78643K 2692 0 sigio 0 0K 0K 78643K 3 0 proc 56 74K 99K 78643K 279 0 subproc 34 2K 2K 78643K 34 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 in_multi 33 2K 2K 78643K 33 0 ether_multi 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 31 148K 148K 78643K 31 0 exec 0 0K 2K 78643K 363 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 413 41K 41K 78643K 33563 0 UVM aobj 3 2K 2K 78643K 3 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 5 0K 0K 78643K 9 0 temp 101 4209K 4273K 78643K 7461 0 kqueue 10 14K 14K 78643K 10 0 SYN cache 2 16K 16K 78643K 2 0 ddb{0}> 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 21 0 18 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 1053 0 1036 1 0 1 1 0 8 0 syncache 296 4 0 4 1 1 0 1 0 8 0 tcpqe 32 2709 0 2709 10 10 0 5 0 8 0 tcpcb 736 10 0 6 1 0 1 1 0 8 0 arp 120 6 0 0 1 0 1 1 0 8 0 inpcb 304 35 0 28 1 0 1 1 0 8 0 nd6 48 6 0 0 1 0 1 1 0 8 0 kcovpl 48 2 0 0 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 189 0 0 12 0 12 12 0 8 0 art_table 32 190 0 0 2 0 2 2 0 8 0 art_node 16 44 0 4 1 0 1 1 0 8 0 sysvmsgpl 40 17 0 10 1 0 1 1 0 8 0 semupl 112 33 0 33 1 1 0 1 0 8 0 semapl 112 42 0 35 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 4554 0 3150 88 0 88 88 0 8 0 ffsino 272 4554 0 3150 95 1 94 94 0 8 0 nchpl 144 8310 0 6696 60 0 60 60 0 8 0 uvmvnodes 72 4597 0 0 84 0 84 84 0 8 0 vnodes 224 4597 0 0 271 0 271 271 0 8 0 namei 1024 17110 0 17110 2 1 1 1 0 8 1 percpumem 16 34 0 0 1 0 1 1 0 8 0 scxspl 216 22928 0 22928 15 14 1 8 0 8 1 plimitpl 152 18 0 8 1 0 1 1 0 8 0 sigapl 424 2914 0 2879 5 1 4 5 0 8 0 futexpl 56 21614 0 21614 1 0 1 1 0 8 1 knotepl 112 52 0 0 2 0 2 2 0 8 0 kqueuepl 216 3408 0 3401 1 0 1 1 0 8 0 pipepl 336 261 0 251 4 2 2 2 0 8 1 fdescpl 496 2898 0 2879 3 0 3 3 0 8 0 filepl 152 9604 0 9489 6 0 6 6 0 8 1 lockfpl 104 890 0 888 1 0 1 1 0 8 0 lockfspl 48 446 0 444 1 0 1 1 0 8 0 sessionpl 144 17 0 7 1 0 1 1 0 8 0 pgrppl 48 17 0 7 1 0 1 1 0 8 0 ucredpl 96 106 0 94 1 0 1 1 0 8 0 zombiepl 144 2879 0 2879 2 1 1 1 0 8 1 processpl 1072 2914 0 2879 3 0 3 3 0 8 0 procpl 672 5902 0 5858 6 1 5 5 0 8 1 sockpl 480 1112 0 1085 8 3 5 5 0 8 1 mcl64k 65536 2 0 0 1 0 1 1 0 8 0 mcl16k 16384 17 0 0 3 0 3 3 0 8 0 mcl12k 12288 18 0 0 2 0 2 2 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 7 0 0 1 0 1 1 0 8 0 mcl4k 4096 18 0 0 3 0 3 3 0 8 0 mcl2k2 2112 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 717 0 0 85 0 85 85 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 781 0 0 47 0 47 47 0 8 0 bufpl 280 6624 0 292 453 0 453 453 0 8 0 anonpl 24 756223 0 691392 395 1 394 394 0 186 0 amapchunkpl 152 79415 0 77449 79 2 77 77 0 158 1 amappl16 200 5919 0 3636 121 0 121 121 0 8 0 amappl14 184 2 0 0 1 0 1 1 0 8 0 amappl13 176 1379 0 1374 1 0 1 1 0 8 0 amappl12 168 1321 0 1315 1 0 1 1 0 8 0 amappl11 160 38 0 28 1 0 1 1 0 8 0 amappl10 152 37 0 32 1 0 1 1 0 8 0 amappl9 144 51 0 47 1 0 1 1 0 8 0 amappl8 136 351 0 312 2 0 2 2 0 8 0 amappl7 128 69 0 55 1 0 1 1 0 8 0 amappl6 120 100 0 92 1 0 1 1 0 8 0 amappl5 112 2051 0 2033 1 0 1 1 0 8 0 amappl4 104 904 0 877 1 0 1 1 0 8 0 amappl3 96 2797 0 2790 1 0 1 1 0 8 0 amappl2 88 1789 0 1735 2 0 2 2 0 8 0 amappl1 80 51608 0 51159 13 3 10 12 0 8 0 amappl 88 33052 0 32702 8 0 8 8 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 2 0 0 1 0 1 1 0 8 0 uaddrrnd 24 2898 0 2879 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2898 0 2879 1 0 1 1 0 8 0 vmmpekpl 168 16837 0 16815 2 0 2 2 0 8 0 vmmpepl 168 335945 0 331978 252 52 200 250 0 357 27 vmsppl 368 2897 0 2879 2 0 2 2 0 8 0 rwobjpl 56 59164 0 55961 46 0 46 46 0 8 0 pdppl 4096 5804 0 5758 72 26 46 50 0 8 0 pvpl 32 1656850 0 1588247 566 5 561 561 0 265 4 pmappl 224 2897 0 2879 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 423 0 32 12 0 12 12 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:440 witness_checkorder(fffffd805e8740a0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd805e8740a0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd805e874090,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd805e874090,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd8062434168,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd8062434168,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd80593c0180,0,ffff8000256bb928,ffff8000256bb8f8,0,0,85903dcd0f155d5b,ffffffff821a9380) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd80593c0180,0,ffff8000256bb928,ffff8000256bb8f8,0,0,85903dcd0f155d5b,ffffffff821a9380) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256bba90,ffff8000256bbac8,ffff8000256bba10,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd806f0d32e8,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256bbc20,20000140) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256bbc20) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256bbe50) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256bbe50) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xe4f43eaeba0, count: -15 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{1}> trace x86_ipi_db(ffff800020d38ff0) 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 Xsyscall() at Xsyscall+0x111 end of kernel end trace frame: 0x7f7fffff6340, count: -4