login: witness: lock order reversal: 1st 0xfffffd806f277a10 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd805f9642c0 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:399 witness_checkorder(fffffd805f9642c0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd805f9642c0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd805f9642b0,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd805f9642b0,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd805b19c950,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd805b19c950,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd805b3bbcb8,0,ffff800023496f58,ffff800023496f28,0,0) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd805b3bbcb8,0,ffff800023496f58,ffff800023496f28,0,0) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000234970c0,ffff8000234970f8,ffff800023497040,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd800857e5c0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff800023497250,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff800023497250) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff800023497480) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800023497480) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xdb3f9abdaa0, count: -15 ddb{1}> show registers rdi 0xffff800021274000 rsi 0x12a0f mp_pdirpa+0x1a09 rbp 0xffff800023496bd0 rbx 0x3 rdx 0xffff800021274000 rcx 0x12a0e mp_pdirpa+0x1a08 rax 0xffffffff81519cc7 db_enter+0x17 r8 0xffffffff81ce7f6c witness_checkorder+0x10cc r9 0x5 r10 0xaf0cc9717766f886 r11 0x7d4d58ccb3f0774a r12 0xfffffd8002da77c0 r13 0 r14 0 r15 0 rip 0xffffffff81519cc8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800023496bc0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.0) pid=23237 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=72, nice=20 forw=0xffffffffffffffff, list=0xffff8000212117a8,0xffffffff828c91c0 process=0xffff8000ffffa5b8 user=0xffff800023492000, vmspace=0xfffffd800857e5c0 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 80390 344968 92606 32767 7 0x10 syz-executor.0 *80390 23237 92606 32767 7 0x4000010 syz-executor.0 49397 125550 59952 32767 3 0x90 nanoslp syz-executor.1 92606 197542 20703 32767 3 0x90 nanoslp syz-executor.0 59952 98841 1834 0 3 0x82 wait syz-executor.1 20703 66386 1834 0 3 0x82 wait syz-executor.0 1834 490982 75737 0 3 0x82 kqread syz-fuzzer 1834 120138 75737 0 3 0x4000082 thrsleep syz-fuzzer 1834 186703 75737 0 3 0x4000082 thrsleep syz-fuzzer 1834 493376 75737 0 3 0x4000082 thrsleep syz-fuzzer 1834 402251 75737 0 3 0x4000082 thrsleep syz-fuzzer 1834 462267 75737 0 3 0x4000082 thrsleep syz-fuzzer 1834 310885 75737 0 3 0x4000082 thrsleep syz-fuzzer 1834 443286 75737 0 3 0x4000082 thrsleep syz-fuzzer 75737 108654 93198 0 3 0x10008a sigsusp ksh 93198 220905 56960 0 3 0x9a select sshd 95584 459713 1 0 3 0x100083 ttyin getty 56960 484518 1 0 3 0x88 select sshd 15664 77683 12555 73 3 0x100090 kqread syslogd 12555 26625 1 0 3 0x100082 netio syslogd 80868 499444 1 0 3 0x100080 kqread resolvd 58523 262364 56426 77 3 0x100092 kqread dhcpleased 39809 320183 56426 77 3 0x100092 kqread dhcpleased 56426 64858 1 0 3 0x80 kqread dhcpleased 66665 106169 0 0 3 0x14200 bored smr 18163 445563 0 0 3 0x14200 pgzero zerothread 35040 364708 0 0 3 0x14200 aiodoned aiodoned 72639 327268 0 0 3 0x14200 syncer update 69827 279383 0 0 3 0x14200 cleaner cleaner 62328 508009 0 0 3 0x14200 reaper reaper 16094 39885 0 0 3 0x14200 pgdaemon pagedaemon 74791 326601 0 0 3 0x14200 bored crynlk 68210 277715 0 0 3 0x14200 bored crypto 41557 505739 0 0 3 0x14200 bored viomb 23414 175573 0 0 3 0x40014200 acpi0 acpi0 43113 256088 0 0 3 0x40014200 idle1 25849 334832 0 0 3 0x14200 bored softnet 98123 192314 0 0 3 0x14200 bored systqmp 46369 466031 0 0 3 0x14200 bored systq 53197 234196 0 0 3 0x40014200 bored softclock 98683 485788 0 0 3 0x40014200 idle0 1 358399 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 80390 (syz-executor.0) thread 0xffff8000212102a8 (23237) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82839278) #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 (0xfffffd806f277a10) #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 10114 6354K 6380K 78643K 11204 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 7 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 0K 78643K 72 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 7 21K 33K 78643K 374 0 sigio 0 0K 0K 78643K 31 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 398 41K 41K 78643K 6252 0 UVM aobj 3 2K 2K 78643K 7 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 2882 0 kqueue 10 14K 14K 78643K 10 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 21 0 18 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 94 0 77 1 0 1 1 0 8 0 syncache 296 4 0 4 1 1 0 1 0 8 0 tcpqe 32 1697 0 1697 1 1 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 37 0 30 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 7 0 7 1 0 1 1 0 8 1 semapl 112 70 0 60 1 0 1 1 0 8 0 shmpl 112 4 0 4 1 0 1 1 0 8 1 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 1831 0 426 88 0 88 88 0 8 0 ffsino 272 1831 0 426 95 1 94 94 0 8 0 nchpl 144 2505 0 889 60 0 60 60 0 8 0 uvmvnodes 72 1874 0 0 35 0 35 35 0 8 0 vnodes 224 1874 0 0 111 0 111 111 0 8 0 namei 1024 6144 0 6144 2 1 1 1 0 8 1 percpumem 16 34 0 0 1 0 1 1 0 8 0 scxspl 216 7113 0 7113 10 9 1 8 0 8 1 plimitpl 152 18 0 8 1 0 1 1 0 8 0 sigapl 424 596 0 562 5 0 5 5 0 8 1 futexpl 56 2758 0 2758 1 0 1 1 0 8 1 knotepl 112 46 0 0 2 0 2 2 0 8 0 kqueuepl 216 512 0 505 1 0 1 1 0 8 0 pipepl 336 82 0 72 2 0 2 2 0 8 1 fdescpl 496 580 0 562 3 0 3 3 0 8 0 filepl 152 2326 0 2211 5 0 5 5 0 8 0 lockfpl 104 13 0 11 1 0 1 1 0 8 0 lockfspl 48 6 0 4 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 73 0 61 1 0 1 1 0 8 0 zombiepl 144 562 0 561 2 1 1 1 0 8 0 processpl 1072 596 0 561 3 0 3 3 0 8 0 procpl 672 1066 0 1023 6 1 5 5 0 8 1 sockpl 480 156 0 129 5 1 4 4 0 8 0 mcl64k 65536 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 2 0 0 1 0 1 1 0 8 0 mcl9k 9216 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 3 0 0 1 0 1 1 0 8 0 mcl2k 2048 1214 0 0 148 0 148 148 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 1265 0 0 77 0 77 77 0 8 0 bufpl 280 3690 0 127 255 0 255 255 0 8 0 anonpl 24 178030 0 120256 353 1 352 352 0 186 3 amapchunkpl 152 15208 0 13268 78 1 77 77 0 158 1 amappl16 200 2433 0 602 97 0 97 97 0 8 0 amappl14 184 7 0 2 1 0 1 1 0 8 0 amappl13 176 198 0 192 1 0 1 1 0 8 0 amappl12 168 3 0 2 2 1 1 1 0 8 0 amappl11 160 45 0 34 1 0 1 1 0 8 0 amappl10 152 33 0 28 1 0 1 1 0 8 0 amappl9 144 239 0 237 1 0 1 1 0 8 0 amappl8 136 532 0 494 2 0 2 2 0 8 0 amappl7 128 254 0 239 1 0 1 1 0 8 0 amappl6 120 109 0 100 1 0 1 1 0 8 0 amappl5 112 344 0 328 1 0 1 1 0 8 0 amappl4 104 513 0 486 1 0 1 1 0 8 0 amappl3 96 209 0 202 1 0 1 1 0 8 0 amappl2 88 601 0 543 2 0 2 2 0 8 0 amappl1 80 12955 0 12521 13 3 10 12 0 8 0 amappl 88 5907 0 5567 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 6 0 4 1 0 1 1 0 8 0 uaddrrnd 24 580 0 562 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 580 0 562 1 0 1 1 0 8 0 vmmpekpl 168 7413 0 7381 2 0 2 2 0 8 0 vmmpepl 168 68661 0 65244 219 0 219 219 0 357 66 vmsppl 368 579 0 562 2 0 2 2 0 8 0 rwobjpl 56 15534 0 12795 39 0 39 39 0 8 0 pdppl 4096 1168 0 1124 72 22 50 50 0 8 6 pvpl 32 392634 0 331291 503 0 503 503 0 265 4 pmappl 224 579 0 562 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 509 0 26 14 0 14 14 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff8276eff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:353 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(ffffffff82839070) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82839070) at __mp_lock+0x129 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: 0x7f7ffffe5490, 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:399 witness_checkorder(fffffd805f9642c0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd805f9642c0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd805f9642b0,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd805f9642b0,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd805b19c950,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd805b19c950,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd805b3bbcb8,0,ffff800023496f58,ffff800023496f28,0,0) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd805b3bbcb8,0,ffff800023496f58,ffff800023496f28,0,0) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000234970c0,ffff8000234970f8,ffff800023497040,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd800857e5c0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff800023497250,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff800023497250) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff800023497480) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800023497480) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xdb3f9abdaa0, count: -15