witness: lock order reversal: 1st 0xfffffd807effe5d8 vmmaplk (&map->lock) 2nd 0xfffffd8065ae3f80 inode (&ip->i_lock) lock order "&ip->i_lock"(rrwlock) -> "&map->lock"(rwlock) first seen at: #0 witness_checkorder+0x65e witness_lock_order_add sys/kern/subr_witness.c:2463 [inline] #0 witness_checkorder+0x65e sys/kern/subr_witness.c:880 #1 rw_enter_read+0x66 sys/kern/kern_rwlock.c:111 #2 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1438 #3 uvm_fault+0x7e sys/uvm/uvm_fault.c:526 #4 pageflttrap+0x254 sys/arch/amd64/amd64/trap.c:219 #5 kerntrap+0xf1 sys/arch/amd64/amd64/trap.c:301 #6 alltraps_kern_meltdown+0x7b #7 copyout+0x53 #8 ffs_read+0x3e2 sys/ufs/ffs/ffs_vnops.c:258 #9 VOP_READ+0xbf sys/kern/vfs_vops.c:247 #10 vn_rdwr+0x10b #11 vmcmd_map_readvn+0xda sys/kern/exec_subr.c:246 #12 exec_process_vmcmds+0xb2 sys/kern/exec_subr.c:143 #13 sys_execve+0x9ff sys/kern/kern_exec.c:461 #14 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #14 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:567 #15 Xsyscall+0x128 lock order "&map->lock"(rwlock) -> "&ip->i_lock"(rrwlock) first seen at: #0 witness_checkorder+0x65e witness_lock_order_add sys/kern/subr_witness.c:2463 [inline] #0 witness_checkorder+0x65e sys/kern/subr_witness.c:880 #1 rw_enter+0xd4 #2 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 #4 vn_lock+0x6c sys/kern/vfs_vnops.c:575 #5 uvn_io+0x2b5 sys/uvm/uvm_vnode.c:1196 #6 uvn_get+0x226 sys/uvm/uvm_vnode.c:1056 #7 uvm_fault+0x1197 sys/uvm/uvm_fault.c:1016 #8 uvm_fault_wire+0x63 sys/uvm/uvm_fault.c:1285 #9 uvm_map_pageable_wire+0x30d sys/uvm/uvm_map.c:2367 #10 sys_mlockall+0x6a sys/uvm/uvm_mmap.c:828 #11 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #11 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:567 #12 Xsyscall+0x128 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:398 witness_checkorder(fffffd8065ae3f80,9,0) at witness_checkorder+0xf5a witness_debugger sys/kern/subr_witness.c:2490 [inline] witness_checkorder(fffffd8065ae3f80,9,0) at witness_checkorder+0xf5a sys/kern/subr_witness.c:1087 rw_enter(fffffd8065ae3f70,81) at rw_enter+0xd4 rrw_enter(fffffd8065ae3f70,81) at rrw_enter+0x88 sys/kern/kern_rwlock.c:462 VOP_LOCK(fffffd8065b05a90,81) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 vn_lock(fffffd8065b05a90,81) at vn_lock+0x6c sys/kern/vfs_vnops.c:575 uvn_io(fffffd806dd1ae60,ffff80002451cbb8,1,2,0) at uvn_io+0x2b5 sys/uvm/uvm_vnode.c:1196 uvn_get(fffffd806dd1ae60,9000,ffff80002451ce10,ffff80002451cdac,0,3) at uvn_get+0x226 sys/uvm/uvm_vnode.c:1056 uvm_fault(fffffd807effe5c0,1b32429000,2,3) at uvm_fault+0x1197 sys/uvm/uvm_fault.c:1016 uvm_fault_wire(fffffd807effe5c0,1b32420000,1b33420000,3) at uvm_fault_wire+0x63 sys/uvm/uvm_fault.c:1285 uvm_map_pageable_wire(fffffd807effe5c0,fffffd8065ad3388,0,387,ffffffff8228a410,0) at uvm_map_pageable_wire+0x30d sys/uvm/uvm_map.c:2367 sys_mlockall(ffff8000234fc510,ffff80002451cfe8,ffff80002451d030) at sys_mlockall+0x6a sys/uvm/uvm_mmap.c:828 syscall(ffff80002451d0b0) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002451d0b0) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:567 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8b878a47f60, count: -14 ddb{1}> show registers rdi 0x3 rsi 0x40000 acpi_pdirpa+0x2be68 rbp 0xffff80002451c810 rbx 0x3 rdx 0xffff800000abcb40 rcx 0x3 rax 0x3ffff acpi_pdirpa+0x2be67 r8 0xffffffff8129a523 witness_checkorder+0xf33 r9 0x5 r10 0xc6723add4215236 r11 0x58dde2d793d983f8 r12 0xffffffff8281d930 w_lodata+0x54430 r13 0 r14 0xffffffff8280f440 w_lodata+0x45f40 r15 0xfffffd8002c8f480 rip 0xffffffff819aafe8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff80002451c800 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=434630 stat=onproc flags process=0 proc=4000000 pri=32, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff8000234fc298,0xffffffff8287f558 process=0xffff8000234ee7f0 user=0xffff800024518000, vmspace=0xfffffd807effe5c0 estcpu=36, cpticks=7, pctcpu=0.0 user=0, sys=7, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 48616 482093 30824 0 7 0 syz-executor.1 *48616 434630 30824 0 7 0x4000000 syz-executor.1 47221 327442 32544 0 2 0 syz-executor.0 47221 259360 32544 0 2 0x4000000 syz-executor.0 18699 292901 0 0 3 0x14200 bored sosplice 30824 45092 13389 0 3 0x82 nanosleep syz-executor.1 32544 506823 13389 0 2 0x2 syz-executor.0 13389 458780 89748 0 3 0x82 thrsleep syz-fuzzer 13389 161554 89748 0 3 0x4000082 thrsleep syz-fuzzer 13389 90493 89748 0 3 0x4000082 thrsleep syz-fuzzer 13389 485651 89748 0 3 0x4000082 thrsleep syz-fuzzer 13389 307266 89748 0 3 0x4000082 thrsleep syz-fuzzer 13389 86190 89748 0 3 0x4000082 thrsleep syz-fuzzer 13389 471113 89748 0 3 0x4000082 kqread syz-fuzzer 13389 181940 89748 0 3 0x4000082 thrsleep syz-fuzzer 89748 91993 6002 0 3 0x10008a pause ksh 6002 458038 60224 0 3 0x92 select sshd 45614 302981 1 0 3 0x100083 ttyin getty 60224 518441 1 0 3 0x80 select sshd 72676 4009 6008 74 3 0x100092 bpf pflogd 6008 43503 1 0 3 0x80 netio pflogd 75470 36722 81843 73 3 0x100090 kqread syslogd 81843 262587 1 0 3 0x100082 netio syslogd 87016 169134 1 77 3 0x100090 poll dhclient 6667 468378 1 0 3 0x80 poll dhclient 83735 256060 0 0 3 0x14200 bored smr 19415 469860 0 0 2 0x14200 zerothread 18745 161217 0 0 3 0x14200 aiodoned aiodoned 9681 354289 0 0 3 0x14200 syncer update 66298 322880 0 0 3 0x14200 cleaner cleaner 31691 293712 0 0 3 0x14200 reaper reaper 7282 113271 0 0 3 0x14200 pgdaemon pagedaemon 83480 319151 0 0 3 0x14200 bored crynlk 63851 396282 0 0 3 0x14200 bored crypto 89160 495218 0 0 3 0x40014200 acpi0 acpi0 48147 194774 0 0 3 0x40014200 idle1 51128 259564 0 0 3 0x14200 bored softnet 71232 346471 0 0 3 0x14200 bored systqmp 25262 369564 0 0 3 0x14200 bored systq 63711 511066 0 0 3 0x40014200 bored softclock 50647 482665 0 0 3 0x40014200 idle0 1 217483 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 48616 (syz-executor.1) thread 0xffff8000234fc510 (434630) shared rwlock vmmaplk r = 0 (0xfffffd807effe5d8) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1164 #1 rw_enter+0x446 sys/kern/kern_rwlock.c:311 #2 vm_map_lock_ln+0xda sys/uvm/uvm_map.c:5452 #3 uvm_map_pageable_all+0x56 sys/uvm/uvm_map.c:2576 #4 sys_mlockall+0x6a sys/uvm/uvm_mmap.c:828 #5 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:567 #6 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8287d770) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1164 #1 syscall+0x3fd mi_syscall sys/sys/syscall_mi.h:93 [inline] #1 syscall+0x3fd sys/arch/amd64/amd64/trap.c:567 #2 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9470 6397K 6527K 78643K 10690 0 pcb 13 8K 8K 78643K 23 0 rtable 107 3K 3K 78643K 219 0 ifaddr 44 10K 11K 78643K 60 0 counters 43 33K 34K 78643K 49 0 ioctlops 0 0K 4K 78643K 1482 0 iov 0 0K 2K 78643K 161 0 mount 1 1K 1K 78643K 1 0 vnodes 1221 77K 77K 78643K 1241 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 5K 78643K 3 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 23 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1824 197K 290K 78643K 13058 0 file desc 6 17K 25K 78643K 5583 0 sigio 0 0K 0K 78643K 3 0 proc 60 63K 95K 78643K 458 0 subproc 32 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 20 0 in_multi 33 2K 2K 78643K 44 0 ether_multi 1 0K 0K 78643K 2 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 202 50K 50K 78643K 12313 0 UVM aobj 7 2K 2K 78643K 7 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 6 0K 0K 78643K 13 0 temp 67 3952K 4016K 78643K 13169 0 kqueue 3 4K 8K 78643K 5 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 arp 64 7 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 96 34 0 32 1 0 1 1 0 8 0 rtentry 112 46 0 1 2 0 2 2 0 8 0 unpcb 120 160 0 150 1 0 1 1 0 8 0 syncache 272 4 0 4 1 1 0 1 0 8 0 tcpqe 32 766 0 766 2 2 0 1 0 8 0 tcpcb 592 14 0 10 1 0 1 1 0 8 0 inpcb 296 88 0 81 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 pfosfp 40 846 0 423 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfstitem 24 13 0 10 1 0 1 1 0 8 0 pfstkey 112 13 0 10 1 0 1 1 0 8 0 pfstate 328 13 0 10 1 0 1 1 0 8 0 pfrule 1360 21 0 16 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 188 0 0 12 0 12 12 0 8 0 art_table 32 189 0 0 2 0 2 2 0 8 0 art_node 16 45 0 4 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 20 0 10 1 0 1 1 0 8 0 shmpl 112 4 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 6986 0 5582 88 0 88 88 0 8 0 ffsino 272 6986 0 5582 95 1 94 94 0 8 0 nchpl 144 12858 0 11252 60 0 60 60 0 8 0 uvmvnodes 72 5926 0 0 108 0 108 108 0 8 0 vnodes 208 5926 0 0 312 0 312 312 0 8 0 namei 1024 26808 0 26808 2 1 1 1 0 8 1 percpumem 16 35 0 3 1 0 1 1 0 8 0 vcpupl 1984 1 0 0 1 0 1 1 0 8 0 vmpool 560 1 0 0 1 0 1 1 0 8 0 scxspl 192 38404 0 38404 8 7 1 7 0 8 1 plimitpl 152 22 0 13 1 0 1 1 0 8 0 sigapl 424 5799 0 5766 4 0 4 4 0 8 0 futexpl 56 23077 0 23077 1 0 1 1 0 8 1 knotepl 112 66 0 46 1 0 1 1 0 8 0 kqueuepl 152 5711 0 5709 1 0 1 1 0 8 0 pipepl 304 96 0 85 3 2 1 2 0 8 0 fdescpl 496 5783 0 5766 3 0 3 3 0 8 0 filepl 152 12805 0 12703 6 1 5 5 0 8 0 lockfpl 104 17 0 16 1 0 1 1 0 8 0 lockfspl 48 8 0 7 1 0 1 1 0 8 0 sessionpl 120 18 0 7 1 0 1 1 0 8 0 pgrppl 48 18 0 7 1 0 1 1 0 8 0 ucredpl 96 104 0 95 1 0 1 1 0 8 0 zombiepl 144 5766 0 5766 2 1 1 1 0 8 1 processpl 1008 5799 0 5766 6 1 5 5 0 8 0 procpl 632 11608 0 11566 5 1 4 4 0 8 0 sosppl 144 2 0 2 1 1 0 1 0 8 0 sockpl 400 282 0 263 3 0 3 3 0 8 0 mcl16k 16384 1 0 0 1 0 1 1 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 3 0 0 1 0 1 1 0 8 0 mcl8k 8192 1 0 0 1 0 1 1 0 8 0 mcl4k 4096 4 0 0 1 0 1 1 0 8 0 mcl2k 2048 230 0 0 28 0 28 28 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 289 0 0 15 0 15 15 0 8 0 bufpl 280 9049 0 2799 447 0 447 447 0 8 0 anonpl 16 377457 0 343548 138 1 137 137 0 124 0 amapchunkpl 152 19202 0 18098 44 1 43 43 0 158 0 amappl16 192 14345 0 13325 51 0 51 51 0 8 0 amappl15 184 2778 0 2776 1 0 1 1 0 8 0 amappl14 176 22 0 18 1 0 1 1 0 8 0 amappl13 168 93 0 89 1 0 1 1 0 8 0 amappl12 160 15 0 11 1 0 1 1 0 8 0 amappl11 152 54 0 39 1 0 1 1 0 8 0 amappl10 144 10 0 6 1 0 1 1 0 8 0 amappl9 136 3140 0 3138 2 1 1 1 0 8 0 amappl8 128 144 0 109 2 0 2 2 0 8 0 amappl7 120 3024 0 3015 1 0 1 1 0 8 0 amappl6 112 67 0 56 1 0 1 1 0 8 0 amappl5 104 5928 0 5908 1 0 1 1 0 8 0 amappl4 96 283 0 255 1 0 1 1 0 8 0 amappl3 88 204 0 197 1 0 1 1 0 8 0 amappl2 80 39832 0 39757 2 0 2 2 0 8 0 amappl1 72 172619 0 172112 26 16 10 19 0 8 0 amappl 80 11963 0 11812 4 0 4 4 0 84 0 dma4096 4096 1 0 1 1 1 0 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 0 1 0 1 1 0 8 0 uaddrrnd 24 5784 0 5766 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5784 0 5766 1 0 1 1 0 8 0 vmmpekpl 168 24099 0 24063 3 1 2 2 0 8 0 vmmpepl 168 706896 0 704475 146 39 107 130 0 357 1 vmsppl 368 5783 0 5766 2 0 2 2 0 8 0 pdppl 4096 11575 0 11533 7 1 6 6 0 8 0 pvpl 32 1262141 0 1224987 304 4 300 300 0 265 0 pmappl 232 5783 0 5766 3 1 2 2 0 8 1 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 264 0 7 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff8271aff0) at x86_ipi_db+0x1a sys/arch/amd64/amd64/db_interface.c:352 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(ffffffff8287d568) at __mp_lock+0x129 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff8287d568) at __mp_lock+0x129 sys/kern/kern_lock.c:147 intr_handler(ffff8000235034e0,ffff80000065bd80) at intr_handler+0x5e sys/arch/amd64/amd64/intr.c:532 Xintr_ioapic_edge4_untramp() at Xintr_ioapic_edge4_untramp+0x19f __mp_lock(ffffffff8287d568) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff8287d568) 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: 0x7f7ffffef9e0, count: -9 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:398 witness_checkorder(fffffd8065ae3f80,9,0) at witness_checkorder+0xf5a witness_debugger sys/kern/subr_witness.c:2490 [inline] witness_checkorder(fffffd8065ae3f80,9,0) at witness_checkorder+0xf5a sys/kern/subr_witness.c:1087 rw_enter(fffffd8065ae3f70,81) at rw_enter+0xd4 rrw_enter(fffffd8065ae3f70,81) at rrw_enter+0x88 sys/kern/kern_rwlock.c:462 VOP_LOCK(fffffd8065b05a90,81) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:603 vn_lock(fffffd8065b05a90,81) at vn_lock+0x6c sys/kern/vfs_vnops.c:575 uvn_io(fffffd806dd1ae60,ffff80002451cbb8,1,2,0) at uvn_io+0x2b5 sys/uvm/uvm_vnode.c:1196 uvn_get(fffffd806dd1ae60,9000,ffff80002451ce10,ffff80002451cdac,0,3) at uvn_get+0x226 sys/uvm/uvm_vnode.c:1056 uvm_fault(fffffd807effe5c0,1b32429000,2,3) at uvm_fault+0x1197 sys/uvm/uvm_fault.c:1016 uvm_fault_wire(fffffd807effe5c0,1b32420000,1b33420000,3) at uvm_fault_wire+0x63 sys/uvm/uvm_fault.c:1285 uvm_map_pageable_wire(fffffd807effe5c0,fffffd8065ad3388,0,387,ffffffff8228a410,0) at uvm_map_pageable_wire+0x30d sys/uvm/uvm_map.c:2367 sys_mlockall(ffff8000234fc510,ffff80002451cfe8,ffff80002451d030) at sys_mlockall+0x6a sys/uvm/uvm_mmap.c:828 syscall(ffff80002451d0b0) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff80002451d0b0) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:567 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8b878a47f60, count: -14