witness: lock order reversal: 1st 0xfffffd806f287c00 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd805826d3d0 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(fffffd805826d3d0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd805826d3d0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd805826d3c0,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd805826d3c0,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd804ebfbd48,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd804ebfbd48,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd804f66db48,0,ffff8000256beb18,ffff8000256beae8,0,0) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd804f66db48,0,ffff8000256beb18,ffff8000256beae8,0,0) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256bec80,ffff8000256becb8,ffff8000256bec00,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd80085822e0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256bee10,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256bee10) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256bf040) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256bf040) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x58a8d986de0, count: -15 ddb{1}> show registers rdi 0xffff800021274000 rsi 0x6f2e __ALIGN_SIZE+0x5f2e rbp 0xffff8000256be790 rbx 0x3 rdx 0xffff800021274000 rcx 0x6f2d __ALIGN_SIZE+0x5f2d rax 0xffffffff81e95847 db_enter+0x17 r8 0xffffffff81fa9eec witness_checkorder+0x10cc r9 0x5 r10 0x7678bec23d03316c r11 0xac80760ae8b4affb r12 0xfffffd8002dab800 r13 0 r14 0 r15 0 rip 0xffffffff81e95848 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000256be780 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=493875 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=78, nice=20 forw=0xffffffffffffffff, list=0xffff800021211ce8,0xffffffff82926830 process=0xffff8000ffffb248 user=0xffff8000256ba000, vmspace=0xfffffd80085822e0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 21659 431995 67352 32767 7 0x10 syz-executor.0 *21659 493875 67352 32767 7 0x4000010 syz-executor.0 13767 262990 94684 32767 2 0x10 syz-executor.1 13767 106228 94684 32767 2 0x4000010 syz-executor.1 94684 507118 53973 32767 3 0x90 nanoslp syz-executor.1 67352 63543 95856 32767 3 0x90 nanoslp syz-executor.0 53973 422524 55177 0 3 0x82 wait syz-executor.1 95856 119604 55177 0 3 0x82 wait syz-executor.0 55177 358759 68891 0 3 0x82 thrsleep syz-fuzzer 55177 183541 68891 0 3 0x4000082 thrsleep syz-fuzzer 55177 213185 68891 0 3 0x4000082 thrsleep syz-fuzzer 55177 322382 68891 0 3 0x4000082 thrsleep syz-fuzzer 55177 115434 68891 0 3 0x4000082 thrsleep syz-fuzzer 55177 207890 68891 0 3 0x4000082 thrsleep syz-fuzzer 55177 123610 68891 0 3 0x4000082 kqread syz-fuzzer 55177 379683 68891 0 3 0x4000082 thrsleep syz-fuzzer 68891 474934 83642 0 3 0x10008a sigsusp ksh 83642 295380 88523 0 3 0x9a select sshd 36933 262693 1 0 3 0x100083 ttyin getty 88523 65793 1 0 3 0x88 select sshd 54545 486978 9554 73 3 0x100090 kqread syslogd 9554 450330 1 0 3 0x100082 netio syslogd 19376 406946 1 0 3 0x100080 kqread resolvd 55754 33865 59429 77 3 0x100092 kqread dhcpleased 9765 340673 59429 77 3 0x100092 kqread dhcpleased 59429 478366 1 0 3 0x80 kqread dhcpleased 98373 482035 0 0 3 0x14200 bored smr 89764 168598 0 0 2 0x14200 zerothread 39695 134626 0 0 3 0x14200 aiodoned aiodoned 84865 508217 0 0 3 0x14200 syncer update 11501 307287 0 0 3 0x14200 cleaner cleaner 5520 242997 0 0 3 0x14200 reaper reaper 24905 217651 0 0 3 0x14200 pgdaemon pagedaemon 54756 329477 0 0 3 0x14200 bored crynlk 86217 57027 0 0 3 0x14200 bored crypto 29252 459892 0 0 3 0x14200 bored viomb 77651 304623 0 0 3 0x40014200 acpi0 acpi0 77861 411358 0 0 3 0x40014200 idle1 51798 427555 0 0 3 0x14200 bored softnet 76257 281848 0 0 3 0x14200 bored systqmp 56161 140059 0 0 3 0x14200 bored systq 99394 220039 0 0 3 0x40014200 bored softclock 6102 67916 0 0 3 0x40014200 idle0 1 371817 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 21659 (syz-executor.0) thread 0xffff8000212117a8 (493875) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8283bba0) #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 (0xfffffd806f287c00) #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 10113 6354K 6380K 78643K 11203 0 pcb 13 8K 8K 78643K 13 0 rtable 106 3K 3K 78643K 1276 0 ifaddr 39 10K 10K 78643K 39 0 counters 44 34K 34K 78643K 44 0 ioctlops 0 0K 2K 78643K 31 0 iov 0 0K 12K 78643K 81 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 6 0 vnodes 1216 76K 76K 78643K 1222 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 12 0K 1K 78643K 136 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 8 25K 33K 78643K 2147 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 ip_moptions 0 0K 0K 78643K 2 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 364 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 674 66K 67K 78643K 27895 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 4205K 4269K 78643K 6372 0 kqueue 10 14K 16K 78643K 22 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 1256 0 1252 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 120 0 105 1 0 1 1 0 8 0 syncache 296 4 0 4 1 1 0 1 0 8 0 tcpqe 32 806 0 806 3 3 0 1 0 8 0 tcpcb 736 12 0 8 1 0 1 1 0 8 0 arp 120 6 0 0 1 0 1 1 0 8 0 inpcb 304 300 0 293 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 semupl 112 9 0 9 1 1 0 1 0 8 0 semapl 112 128 0 118 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 3578 0 2174 88 0 88 88 0 8 0 ffsino 272 3578 0 2174 95 1 94 94 0 8 0 nchpl 144 6014 0 4400 60 0 60 60 0 8 0 uvmvnodes 72 3621 0 0 66 0 66 66 0 8 0 vnodes 224 3621 0 0 213 0 213 213 0 8 0 namei 1024 13583 0 13583 2 1 1 1 0 8 1 percpumem 16 34 0 0 1 0 1 1 0 8 0 scxspl 216 17905 0 17905 12 11 1 8 0 8 1 plimitpl 152 18 0 8 1 0 1 1 0 8 0 sigapl 424 2369 0 2334 5 1 4 5 0 8 0 futexpl 56 15688 0 15688 1 0 1 1 0 8 1 knotepl 112 46 0 0 2 0 2 2 0 8 0 kqueuepl 216 3735 0 3728 2 1 1 2 0 8 0 pipepl 336 136 0 126 2 1 1 2 0 8 0 fdescpl 496 2353 0 2334 3 0 3 3 0 8 0 filepl 152 9333 0 9219 6 1 5 6 0 8 0 lockfpl 104 89 0 86 1 0 1 1 0 8 0 lockfspl 48 43 0 40 1 0 1 1 0 8 0 sessionpl 144 17 0 7 1 0 1 1 0 8 0 pgrppl 48 144 0 134 1 0 1 1 0 8 0 ucredpl 96 109 0 97 1 0 1 1 0 8 0 zombiepl 144 2334 0 2334 2 1 1 1 0 8 1 processpl 1072 2369 0 2334 3 0 3 3 0 8 0 procpl 672 5012 0 4968 6 2 4 5 0 8 0 sockpl 480 1688 0 1662 7 3 4 5 0 8 0 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 mcl16k 16384 2 0 0 1 0 1 1 0 8 0 mcl12k 12288 7 0 0 1 0 1 1 0 8 0 mcl9k 9216 16 0 0 2 0 2 2 0 8 0 mcl8k 8192 17 0 0 3 0 3 3 0 8 0 mcl4k 4096 17 0 0 3 0 3 3 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 278 0 0 34 1 33 34 0 8 1 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 1052 0 0 60 0 60 60 0 8 0 bufpl 280 5534 0 127 387 0 387 387 0 8 0 anonpl 24 716701 0 603382 697 4 693 695 0 186 0 amapchunkpl 152 68562 0 64366 164 1 163 163 0 158 1 amappl16 200 6472 0 3328 166 0 166 166 0 8 0 amappl15 192 2 0 0 1 0 1 1 0 8 0 amappl14 184 1064 0 1062 1 0 1 1 0 8 0 amappl13 176 34 0 33 1 0 1 1 0 8 0 amappl12 168 20 0 17 1 0 1 1 0 8 0 amappl11 160 57 0 45 1 0 1 1 0 8 0 amappl10 152 37 0 31 1 0 1 1 0 8 0 amappl9 144 1300 0 1293 1 0 1 1 0 8 0 amappl8 136 344 0 305 2 0 2 2 0 8 0 amappl7 128 67 0 54 1 0 1 1 0 8 0 amappl6 120 1173 0 1158 1 0 1 1 0 8 0 amappl5 112 1235 0 1218 1 0 1 1 0 8 0 amappl4 104 1584 0 1554 1 0 1 1 0 8 0 amappl3 96 82 0 81 1 0 1 1 0 8 0 amappl2 88 548 0 493 2 0 2 2 0 8 0 amappl1 80 43878 0 43431 13 3 10 12 0 8 0 amappl 88 27394 0 26779 14 0 14 14 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 2353 0 2334 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 2353 0 2334 1 0 1 1 0 8 0 vmmpekpl 168 14299 0 14267 2 0 2 2 0 8 0 vmmpepl 168 274469 0 269369 352 34 318 352 0 357 96 vmsppl 368 2352 0 2334 2 0 2 2 0 8 0 rwobjpl 56 50861 0 46540 63 1 62 62 0 8 1 pdppl 4096 4714 0 4668 72 26 46 50 0 8 0 pvpl 32 1389979 0 1272962 966 9 957 964 0 265 0 pmappl 224 2352 0 2334 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 383 0 32 11 0 11 11 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff82816ff0) 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(ffffffff8283b998) at __mp_lock+0x120 __mp_lock_spin sys/kern/kern_lock.c:117 [inline] __mp_lock(ffffffff8283b998) at __mp_lock+0x120 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: 0x7f7ffffcbc50, 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(fffffd805826d3d0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd805826d3d0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd805826d3c0,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd805826d3c0,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd804ebfbd48,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd804ebfbd48,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd804f66db48,0,ffff8000256beb18,ffff8000256beae8,0,0) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd804f66db48,0,ffff8000256beb18,ffff8000256beae8,0,0) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256bec80,ffff8000256becb8,ffff8000256bec00,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd80085822e0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256bee10,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256bee10) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256bf040) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256bf040) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x58a8d986de0, count: -15