witness: lock order reversal: 1st 0xfffffd806f22adf0 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd8065599d60 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(fffffd8065599d60,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8065599d60,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd8065599d50,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd8065599d50,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd8069053638,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:534 vn_lock(fffffd8069053638,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8065500378,0,ffff8000256c7058,ffff8000256c7028,0,0,a9edf4dcff5db3d6,ffffffff814e9700) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8065500378,0,ffff8000256c7058,ffff8000256c7028,0,0,a9edf4dcff5db3d6,ffffffff814e9700) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256c71c0,ffff8000256c71f8,ffff8000256c7140,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd807effb8a0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256c7350,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256c7350) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256c7580) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256c7580) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6fb8bf93180, count: -15 ddb{1}> show registers rdi 0xffff800023494000 rsi 0x6e3f __ALIGN_SIZE+0x5e3f rbp 0xffff8000256c6cd0 rbx 0x3 rdx 0xffff800023494000 rcx 0x6e3e __ALIGN_SIZE+0x5e3e rax 0xffffffff813bc4d7 db_enter+0x17 r8 0xffffffff8149defc witness_checkorder+0x10cc r9 0x5 r10 0x202b4e125bc3d51b r11 0xcf376334a55ff6fd r12 0xfffffd8002dc1900 r13 0 r14 0 r15 0 rip 0xffffffff813bc4d8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000256c6cc0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=505969 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=77, nice=20 forw=0xffffffffffffffff, list=0xffff800021256d20,0xffffffff82960ff8 process=0xffff8000ffff9928 user=0xffff8000256c2000, vmspace=0xfffffd807effb8a0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 81927 27719 19190 32767 7 0x10 syz-executor.1 *81927 505969 19190 32767 7 0x4000010 syz-executor.1 20758 157724 23335 32767 2 0x10 syz-executor.0 20758 444909 23335 32767 3 0x4000090 fsleep syz-executor.0 19190 46704 40632 32767 3 0x90 nanoslp syz-executor.1 40632 398057 79866 0 3 0x82 wait syz-executor.1 51181 472384 0 0 3 0x14200 bored sosplice 23335 91153 2162 32767 3 0x90 nanoslp syz-executor.0 2162 440759 79866 0 3 0x82 wait syz-executor.0 79866 113248 16147 0 3 0x82 thrsleep syz-fuzzer 79866 404307 16147 0 3 0x4000082 nanoslp syz-fuzzer 79866 210048 16147 0 3 0x4000082 thrsleep syz-fuzzer 79866 306546 16147 0 3 0x4000082 kqread syz-fuzzer 79866 273243 16147 0 3 0x4000082 thrsleep syz-fuzzer 79866 474948 16147 0 3 0x4000082 thrsleep syz-fuzzer 79866 461995 16147 0 3 0x4000082 thrsleep syz-fuzzer 79866 115094 16147 0 3 0x4000082 thrsleep syz-fuzzer 16147 409693 83127 0 3 0x10008a sigsusp ksh 83127 518661 67344 0 3 0x9a select sshd 87782 83089 1 0 3 0x100083 ttyin getty 67344 386446 1 0 3 0x88 select sshd 1538 493652 19140 73 3 0x100090 kqread syslogd 19140 263632 1 0 3 0x100082 netio syslogd 59280 406022 1 0 3 0x100080 kqread resolvd 78469 28818 39686 77 3 0x100092 kqread dhcpleased 82554 416754 39686 77 3 0x100092 kqread dhcpleased 39686 80249 1 0 3 0x80 kqread dhcpleased 92157 126124 0 0 3 0x14200 bored smr 44381 76804 0 0 2 0x14200 zerothread 22501 427789 0 0 3 0x14200 aiodoned aiodoned 59064 348992 0 0 3 0x14200 syncer update 41896 349659 0 0 3 0x14200 cleaner cleaner 39633 80987 0 0 3 0x14200 reaper reaper 63774 36226 0 0 3 0x14200 pgdaemon pagedaemon 95539 388030 0 0 3 0x14200 bored crynlk 9336 221259 0 0 3 0x14200 bored crypto 80724 170510 0 0 3 0x14200 bored viomb 64216 176593 0 0 3 0x40014200 acpi0 acpi0 68962 517049 0 0 3 0x40014200 idle1 98304 299209 0 0 3 0x14200 bored softnet 21204 421065 0 0 3 0x14200 bored systqmp 71451 346625 0 0 3 0x14200 bored systq 96739 274770 0 0 3 0x40014200 bored softclock 14173 220310 0 0 3 0x40014200 idle0 1 273715 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 81927 (syz-executor.1) thread 0xffff800021257ce0 (505969) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff828ae030) #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 (0xfffffd806f22adf0) #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 11222 0 pcb 13 8K 8K 78643K 13 0 rtable 114 3K 4K 78643K 502 0 ifaddr 39 10K 10K 78643K 76 0 sysctl 3 1K 1K 78643K 3 0 counters 44 34K 34K 78643K 54 0 ioctlops 0 0K 2K 78643K 162 0 iov 0 0K 32K 78643K 372 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1216 76K 77K 78643K 1462 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 35 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 7173 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 8 25K 33K 78643K 10009 0 sigio 0 0K 0K 78643K 49 0 proc 56 74K 98K 78643K 582 0 subproc 34 2K 2K 78643K 119 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 649 0 in_multi 33 2K 2K 78643K 305 0 ether_multi 1 0K 0K 78643K 45 0 mrt 1 0K 0K 78643K 1 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 1162 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 410 54K 62K 78643K 124301 0 UVM aobj 80 3K 3K 78643K 102 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 222 0 NDP 5 0K 0K 78643K 24 0 temp 102 4213K 4277K 78643K 23011 0 kqueue 10 14K 19K 78643K 293 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 120 226 0 223 1 0 1 1 0 8 0 rtentry 112 109 0 61 2 0 2 2 0 8 0 unpcb 120 2790 0 2771 2 1 1 2 0 8 0 syncache 296 115 0 115 13 13 0 1 0 8 0 tcpqe 32 61 0 61 9 9 0 1 0 8 0 tcpcb 736 1797 0 1790 26 24 2 6 0 8 0 arp 120 18 0 11 1 0 1 1 0 8 0 ipq 40 3 0 3 2 1 1 1 0 8 1 ipqe 40 12 0 12 2 1 1 1 0 8 1 inpcb 304 3305 0 3293 7 5 2 4 0 8 0 ip6q 72 4 0 4 2 2 0 1 0 8 0 ip6af 40 7 0 7 2 2 0 1 0 8 0 nd6 48 28 0 19 1 0 1 1 0 8 0 kcovpl 48 7 0 5 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 436 0 231 15 2 13 13 0 8 0 art_table 32 437 0 231 2 0 2 2 0 8 0 art_node 16 108 0 64 1 0 1 1 0 8 0 semupl 112 10 0 10 1 1 0 1 0 8 0 semapl 112 7161 0 7151 1 0 1 1 0 8 0 shmpl 112 99 0 22 3 0 3 3 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 12655 0 11203 96 5 91 92 0 8 0 ffsino 272 12655 0 11203 98 0 98 98 0 8 0 nchpl 144 26027 0 24426 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 59016 0 59016 1 0 1 1 0 8 1 percpumem 16 39 0 5 1 0 1 1 0 8 0 scxspl 216 71196 0 71196 15 14 1 8 0 8 1 plimitpl 152 229 0 219 1 0 1 1 0 8 0 sigapl 424 10219 0 10183 6 1 5 5 0 8 1 futexpl 56 131100 0 131099 1 0 1 1 0 8 0 knotepl 112 60 0 0 2 0 2 2 0 8 0 kqueuepl 216 13718 0 13709 5 4 1 2 0 8 0 pipepl 336 1369 0 1359 13 11 2 2 0 8 1 fdescpl 496 10202 0 10183 3 0 3 3 0 8 0 filepl 152 41307 0 41192 12 7 5 7 0 8 0 lockfpl 104 1059 0 1056 1 0 1 1 0 8 0 lockfspl 48 371 0 368 1 0 1 1 0 8 0 sessionpl 144 22 0 12 1 0 1 1 0 8 0 pgrppl 48 33 0 23 1 0 1 1 0 8 0 ucredpl 96 2656 0 2644 1 0 1 1 0 8 0 zombiepl 144 10183 0 10183 1 0 1 1 0 8 1 processpl 1072 10219 0 10183 3 0 3 3 0 8 0 procpl 672 22832 0 22787 12 7 5 5 0 8 1 sosppl 168 130 0 129 1 0 1 1 0 8 0 sockpl 480 6387 0 6355 18 13 5 7 0 8 0 mcl64k 65536 25 0 0 4 0 4 4 0 8 0 mcl16k 16384 33 0 0 4 1 3 3 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 16 0 0 2 0 2 2 0 8 0 mcl8k 8192 18 0 0 3 0 3 3 0 8 0 mcl4k 4096 33 0 0 3 0 3 3 0 8 0 mcl2k2 2112 17 0 0 2 0 2 2 0 8 0 mcl2k 2048 237 0 0 19 0 19 19 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 1310 0 0 66 0 66 66 0 8 0 bufpl 280 14792 0 8468 453 0 453 453 0 8 0 anonpl 24 2661809 0 2638536 175 31 144 144 0 186 0 amapchunkpl 152 292286 0 291198 73 30 43 43 0 158 1 amappl16 200 18462 0 17922 41 12 29 29 0 8 0 amappl15 192 81 0 75 1 0 1 1 0 8 0 amappl14 184 2 0 2 2 2 0 1 0 8 0 amappl13 176 913 0 912 1 0 1 1 0 8 0 amappl12 168 26 0 24 1 0 1 1 0 8 0 amappl11 160 3432 0 3415 1 0 1 1 0 8 0 amappl10 152 25 0 20 1 0 1 1 0 8 0 amappl9 144 6143 0 6138 1 0 1 1 0 8 0 amappl8 136 747 0 579 6 0 6 6 0 8 0 amappl7 128 76 0 66 1 0 1 1 0 8 0 amappl6 120 5898 0 5882 1 0 1 1 0 8 0 amappl5 112 10313 0 10292 1 0 1 1 0 8 0 amappl4 104 4213 0 4179 1 0 1 1 0 8 0 amappl3 96 869 0 853 1 0 1 1 0 8 0 amappl2 88 1532 0 1489 9 8 1 3 0 8 0 amappl1 80 175666 0 175210 12 2 10 12 0 8 0 amappl 88 121202 0 120960 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 64 101 0 22 2 0 2 2 0 8 0 uaddrrnd 24 10202 0 10183 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 10202 0 10183 1 0 1 1 0 8 0 vmmpekpl 168 56167 0 56144 2 0 2 2 0 8 0 vmmpepl 168 1180399 0 1178091 116 14 102 102 0 357 1 vmsppl 368 10201 0 10183 2 0 2 2 0 8 0 rwobjpl 56 200393 0 198924 25 4 21 21 0 8 0 pdppl 4096 20412 0 20366 64 18 46 50 0 8 0 pvpl 32 6426170 0 6399214 321 96 225 226 0 265 4 pmappl 224 10201 0 10183 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 421 0 63 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(ffffffff827b9ff0) 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(ffffffff828ade28) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff828ade28) 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: 0x7f7ffffdcef0, 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(fffffd8065599d60,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8065599d60,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd8065599d50,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd8065599d50,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd8069053638,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:534 vn_lock(fffffd8069053638,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8065500378,0,ffff8000256c7058,ffff8000256c7028,0,0,a9edf4dcff5db3d6,ffffffff814e9700) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8065500378,0,ffff8000256c7058,ffff8000256c7028,0,0,a9edf4dcff5db3d6,ffffffff814e9700) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000256c71c0,ffff8000256c71f8,ffff8000256c7140,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd807effb8a0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000256c7350,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000256c7350) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000256c7580) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000256c7580) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x6fb8bf93180, count: -15