witness: lock order reversal: 1st 0xfffffd806f1f9df0 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd8068e4a1b8 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(fffffd8068e4a1b8,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8068e4a1b8,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd8068e4a1a8,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd8068e4a1a8,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd80698a7a20,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd80698a7a20,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8069d2e370,0,ffff800023460e48,ffff800023460e18,0,2,856dcbe2ef7fcdf,ffffffff81da88c0) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8069d2e370,0,ffff800023460e48,ffff800023460e18,0,2,856dcbe2ef7fcdf,ffffffff81da88c0) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff800023460fb0,ffff800023460fe8,ffff800023460f30,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd807effa000,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff800023461140,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff800023461140) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff800023461380) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800023461380) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xa42b9a8a2d0, count: -15 ddb{1}> show registers rdi 0xffff800023494000 rsi 0x6f7d __ALIGN_SIZE+0x5f7d rbp 0xffff800023460ac0 rbx 0x3 rdx 0xffff800023494000 rcx 0x6f7c __ALIGN_SIZE+0x5f7c rax 0xffffffff81d423a7 db_enter+0x17 r8 0xffffffff810f824c witness_checkorder+0x10cc r9 0x5 r10 0x8bf3ba344b496165 r11 0x59c3e1145acb4c76 r12 0xfffffd8002db6880 r13 0 r14 0 r15 0 rip 0xffffffff81d423a8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800023460ab0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=247220 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=78, nice=20 forw=0xffffffffffffffff, list=0xffff800021211ce0,0xffff800021210550 process=0xffff8000ffff8868 user=0xffff80002345c000, vmspace=0xfffffd807effa000 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 85285 29667 82663 32767 2 0x10 syz-executor.0 210 316767 66183 32767 7 0x10 syz-executor.1 * 210 247220 66183 32767 7 0x4000010 syz-executor.1 82663 161999 4552 32767 3 0x90 nanoslp syz-executor.0 4552 181850 2132 0 3 0x82 wait syz-executor.0 66183 156400 56645 32767 3 0x90 nanoslp syz-executor.1 56645 411549 2132 0 3 0x82 wait syz-executor.1 75734 223973 0 0 3 0x14200 bored sosplice 2132 394178 28496 0 3 0x82 thrsleep syz-fuzzer 2132 394607 28496 0 3 0x4000082 nanoslp syz-fuzzer 2132 260181 28496 0 3 0x4000082 thrsleep syz-fuzzer 2132 235476 28496 0 3 0x4000082 thrsleep syz-fuzzer 2132 95457 28496 0 3 0x4000082 kqread syz-fuzzer 2132 147784 28496 0 3 0x4000082 thrsleep syz-fuzzer 2132 201752 28496 0 3 0x4000082 nanoslp syz-fuzzer 2132 368905 28496 0 3 0x4000082 thrsleep syz-fuzzer 28496 232111 25750 0 3 0x10008a sigsusp ksh 25750 199413 15931 0 3 0x9a select sshd 15717 59878 1 0 3 0x100083 ttyin getty 15931 58700 1 0 3 0x88 select sshd 6192 441363 84558 73 3 0x100090 kqread syslogd 84558 197426 1 0 3 0x100082 netio syslogd 15236 54156 1 0 3 0x100080 kqread resolvd 43005 130857 83435 77 3 0x100092 kqread dhcpleased 44717 384923 83435 77 3 0x100092 kqread dhcpleased 83435 148095 1 0 3 0x80 kqread dhcpleased 81961 264404 0 0 3 0x14200 bored smr 5929 169463 0 0 2 0x14200 zerothread 3261 420315 0 0 3 0x14200 aiodoned aiodoned 24819 442776 0 0 3 0x14200 syncer update 66985 232159 0 0 3 0x14200 cleaner cleaner 16924 517599 0 0 3 0x14200 reaper reaper 69542 379667 0 0 3 0x14200 pgdaemon pagedaemon 94750 498268 0 0 3 0x14200 bored crynlk 4212 104981 0 0 3 0x14200 bored crypto 97637 404347 0 0 3 0x14200 bored viomb 4241 317255 0 0 3 0x40014200 acpi0 acpi0 61248 440616 0 0 3 0x40014200 idle1 43864 205732 0 0 3 0x14200 bored softnet 74115 485800 0 0 3 0x14200 bored systqmp 97305 319775 0 0 3 0x14200 bored systq 55839 144494 0 0 3 0x40014200 bored softclock 19909 5584 0 0 3 0x40014200 idle0 1 160976 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 210 (syz-executor.1) thread 0xffff800021210fc0 (247220) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82a03790) #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 (0xfffffd806f1f9df0) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182 #1 dopipe+0xd6 #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 10116 6407K 6433K 78643K 11242 0 pcb 13 8K 8K 78643K 13 0 rtable 108 3K 3K 78643K 627 0 ifaddr 39 10K 10K 78643K 127 0 sysctl 3 1K 1K 78643K 3 0 counters 44 34K 34K 78643K 68 0 ioctlops 0 0K 2K 78643K 247 0 iov 0 0K 24K 78643K 567 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 6 0 vnodes 1217 77K 77K 78643K 1578 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 38 0 VM map 2 1K 1K 78643K 2 0 sem 11 1K 1K 78643K 25 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 8 25K 33K 78643K 29124 0 sigio 0 0K 0K 78643K 61 0 proc 56 74K 99K 78643K 820 0 subproc 34 2K 2K 78643K 238 0 NFS srvsock 1 0K 0K 78643K 1 0 NFS daemon 1 16K 16K 78643K 1 0 ip_moptions 0 0K 0K 78643K 650 0 in_multi 33 2K 2K 78643K 302 0 ether_multi 1 0K 0K 78643K 21 0 mrt 0 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 43 201K 201K 78643K 43 0 exec 0 0K 2K 78643K 1346 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 49K 59K 78643K 348366 0 UVM aobj 131 4K 4K 78643K 157 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 124 0 NDP 5 0K 0K 78643K 45 0 temp 102 4213K 4277K 78643K 61908 0 kqueue 10 14K 19K 78643K 373 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 120 240 0 237 1 0 1 1 0 8 0 rtentry 112 185 0 140 2 0 2 2 0 8 0 unpcb 120 3759 0 3740 3 2 1 2 0 8 0 syncache 296 111 0 111 13 13 0 1 0 8 0 tcpqe 32 420 0 420 12 12 0 1 0 8 0 tcpcb 736 1662 0 1658 17 16 1 4 0 8 0 arp 120 32 0 26 1 0 1 1 0 8 0 ipq 40 5 0 5 3 3 0 1 0 8 0 ipqe 40 19 0 19 3 3 0 1 0 8 0 inpcb 304 9359 0 9352 14 13 1 3 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 nd6 48 48 0 41 1 0 1 1 0 8 0 kcovpl 48 14 0 12 1 0 1 1 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 771 0 577 16 3 13 14 0 8 0 art_table 32 772 0 577 2 0 2 2 0 8 0 art_node 16 184 0 143 1 0 1 1 0 8 0 sysvmsgpl 40 12 0 4 1 0 1 1 0 8 0 semupl 112 6 0 6 1 1 0 1 0 8 0 semapl 112 15 0 6 1 0 1 1 0 8 0 shmpl 112 154 0 26 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 31996 0 30573 93 3 90 90 0 8 0 ffsino 272 31996 0 30573 96 0 96 96 0 8 0 nchpl 144 65128 0 63526 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 141611 0 141611 3 2 1 1 0 8 1 percpumem 16 46 0 12 1 0 1 1 0 8 0 scxspl 216 186784 0 186784 14 13 1 8 0 8 1 plimitpl 152 212 0 202 1 0 1 1 0 8 0 sigapl 424 29311 0 29275 6 1 5 5 0 8 0 futexpl 56 258586 0 258586 3 2 1 1 0 8 1 knotepl 112 78 0 0 2 0 2 2 0 8 0 kqueuepl 216 43492 0 43472 5 3 2 2 0 8 0 pipepl 336 1174 0 1163 17 16 1 2 0 8 0 fdescpl 496 29294 0 29275 3 0 3 3 0 8 0 filepl 152 102324 0 102211 8 3 5 6 0 8 0 lockfpl 104 1520 0 1516 1 0 1 1 0 8 0 lockfspl 48 662 0 658 1 0 1 1 0 8 0 sessionpl 144 29 0 19 1 0 1 1 0 8 0 pgrppl 48 70 0 60 1 0 1 1 0 8 0 ucredpl 96 2968 0 2956 1 0 1 1 0 8 0 zombiepl 144 29275 0 29275 2 1 1 1 0 8 1 processpl 1072 29311 0 29275 3 0 3 3 0 8 0 procpl 672 62144 0 62100 16 12 4 5 0 8 0 sosppl 168 105 0 105 12 12 0 1 0 8 0 sockpl 480 13558 0 13529 12 6 6 8 0 8 0 mcl64k 65536 25 0 0 3 0 3 3 0 8 0 mcl16k 16384 25 0 0 4 1 3 3 0 8 0 mcl12k 12288 25 0 0 2 0 2 2 0 8 0 mcl9k 9216 21 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 3 0 3 3 0 8 0 mcl4k 4096 35 0 0 4 1 3 3 0 8 0 mcl2k2 2112 17 0 0 2 0 2 2 0 8 0 mcl2k 2048 746 0 0 35 0 35 35 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 1272 0 0 74 3 71 74 0 8 0 bufpl 280 33996 0 27664 453 0 453 453 0 8 0 anonpl 24 7394759 0 7366624 230 58 172 172 0 186 2 amapchunkpl 152 818715 0 818048 49 22 27 34 0 158 1 amappl16 200 46907 0 45671 115 49 66 74 0 8 0 amappl15 192 10023 0 10021 4 3 1 1 0 8 0 amappl14 184 14 0 13 1 0 1 1 0 8 0 amappl13 176 2992 0 2989 1 0 1 1 0 8 0 amappl12 168 1152 0 1149 1 0 1 1 0 8 0 amappl11 160 37 0 27 1 0 1 1 0 8 0 amappl10 152 2727 0 2721 1 0 1 1 0 8 0 amappl9 144 12468 0 12462 1 0 1 1 0 8 0 amappl8 136 899 0 726 6 0 6 6 0 8 0 amappl7 128 125 0 112 1 0 1 1 0 8 0 amappl6 120 12666 0 12637 1 0 1 1 0 8 0 amappl5 112 28757 0 28738 1 0 1 1 0 8 0 amappl4 104 1181 0 1155 1 0 1 1 0 8 0 amappl3 96 4875 0 4873 1 0 1 1 0 8 0 amappl2 88 4958 0 4900 2 0 2 2 0 8 0 amappl1 80 496066 0 495622 12 2 10 12 0 8 0 amappl 88 343794 0 343585 5 0 5 5 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 64 156 0 26 3 0 3 3 0 8 0 uaddrrnd 24 29294 0 29275 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 29294 0 29275 1 0 1 1 0 8 0 vmmpekpl 168 129368 0 129345 2 0 2 2 0 8 0 vmmpepl 168 3352427 0 3349499 310 181 129 183 0 357 0 vmsppl 368 29293 0 29275 2 0 2 2 0 8 0 rwobjpl 56 555254 0 553143 51 20 31 32 0 8 1 pdppl 4096 58596 0 58550 75 29 46 50 0 8 0 pvpl 32 15979076 0 15947233 353 91 262 267 0 265 2 pmappl 224 29293 0 29275 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 449 0 76 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(ffffffff827f1ff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x3e kd_curproc sys/dev/kcov.c:571 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x3e sys/dev/kcov.c:143 __mp_lock(ffffffff82a03588) at __mp_lock+0x133 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82a03588) at __mp_lock+0x133 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: 0x7f7ffffe9180, count: -7 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(fffffd8068e4a1b8,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8068e4a1b8,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd8068e4a1a8,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd8068e4a1a8,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd80698a7a20,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd80698a7a20,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8069d2e370,0,ffff800023460e48,ffff800023460e18,0,2,856dcbe2ef7fcdf,ffffffff81da88c0) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8069d2e370,0,ffff800023460e48,ffff800023460e18,0,2,856dcbe2ef7fcdf,ffffffff81da88c0) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff800023460fb0,ffff800023460fe8,ffff800023460f30,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd807effa000,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff800023461140,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff800023461140) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff800023461380) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800023461380) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xa42b9a8a2d0, count: -15