witness: lock order reversal: 1st 0xfffffd807effe468 vmmaplk (&map->lock) 2nd 0xfffffd806540f918 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 kpageflttrap+0x210 sys/arch/amd64/amd64/trap.c:268 #5 kerntrap+0xef sys/arch/amd64/amd64/trap.c:323 #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:253 #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:589 #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:614 #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_mlock+0x180 sys/uvm/uvm_mmap.c:772 #11 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #11 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:589 #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(fffffd806540f918,9,0) at witness_checkorder+0xf5a witness_debugger sys/kern/subr_witness.c:2490 [inline] witness_checkorder(fffffd806540f918,9,0) at witness_checkorder+0xf5a sys/kern/subr_witness.c:1087 rw_enter(fffffd806540f908,81) at rw_enter+0xd4 rrw_enter(fffffd806540f908,81) at rrw_enter+0x88 sys/kern/kern_rwlock.c:462 VOP_LOCK(fffffd8062d490d8,81) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:614 vn_lock(fffffd8062d490d8,81) at vn_lock+0x6c sys/kern/vfs_vnops.c:575 uvn_io(fffffd807865a768,ffff800025722068,1,2,0) at uvn_io+0x2b5 sys/uvm/uvm_vnode.c:1196 uvn_get(fffffd807865a768,0,ffff8000257222c0,ffff80002572225c,0,5) at uvn_get+0x226 sys/uvm/uvm_vnode.c:1056 uvm_fault(fffffd807effe450,20000000,2,5) at uvm_fault+0x1197 sys/uvm/uvm_fault.c:1016 uvm_fault_wire(fffffd807effe450,20000000,20004000,5) at uvm_fault_wire+0x63 sys/uvm/uvm_fault.c:1285 uvm_map_pageable_wire(fffffd807effe450,fffffd8079265750,fffffd8079265b40,231,ffffffff81a80d0e,0) at uvm_map_pageable_wire+0x30d sys/uvm/uvm_map.c:2367 sys_mlock(ffff8000ffffb3d8,ffff8000257224a8,ffff8000257224f0) at sys_mlock+0x180 sys/uvm/uvm_mmap.c:772 syscall(ffff800025722570) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800025722570) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:589 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xdacaf106eb0, count: -14 ddb{1}> show registers rdi 0x3 rsi 0x40000 acpi_pdirpa+0x2be68 rbp 0xffff800025721cc0 rbx 0x3 rdx 0xffff800000afe000 rcx 0x3 rax 0x3ffff acpi_pdirpa+0x2be67 r8 0xffffffff81a7e9b3 witness_checkorder+0xf33 r9 0x5 r10 0x9d38e19b24faa397 r11 0xa11bba4960945c3b r12 0xffffffff8284c370 w_lodata+0x546f0 r13 0 r14 0xffffffff82839b20 w_lodata+0x41ea0 r15 0xfffffd8002c8f480 rip 0xffffffff82156c28 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800025721cb0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=368010 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=78, nice=20 forw=0xffffffffffffffff, list=0xffff8000ffffa508,0xffffffff82893e08 process=0xffff8000ffff97a8 user=0xffff80002571d000, vmspace=0xfffffd807effe450 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 89992 296882 17483 32767 7 0x10 syz-executor.1 89992 235015 17483 32767 3 0x4000010 vinvalbuf syz-executor.1 89992 123572 17483 32767 2 0x4000010 syz-executor.1 *89992 368010 17483 32767 7 0x4000010 syz-executor.1 17483 492400 99219 32767 3 0x90 nanosleep syz-executor.1 73205 40207 43260 32767 3 0x90 nanosleep syz-executor.0 99219 323941 42243 0 3 0x82 wait syz-executor.1 43260 184400 42243 0 3 0x82 wait syz-executor.0 42243 344611 12447 0 3 0x82 thrsleep syz-fuzzer 42243 485989 12447 0 3 0x4000082 nanosleep syz-fuzzer 42243 435700 12447 0 3 0x4000082 thrsleep syz-fuzzer 42243 458619 12447 0 3 0x4000082 thrsleep syz-fuzzer 42243 216057 12447 0 3 0x4000082 thrsleep syz-fuzzer 42243 378310 12447 0 3 0x4000082 thrsleep syz-fuzzer 42243 95922 12447 0 3 0x4000082 nanosleep syz-fuzzer 42243 20824 12447 0 3 0x4000082 kqread syz-fuzzer 12447 154527 13001 0 3 0x10008a pause ksh 13001 331534 89431 0 3 0x92 select sshd 65856 321193 1 0 3 0x100083 ttyin getty 89431 117912 1 0 3 0x80 select sshd 1836 430754 4513 73 3 0x100090 kqread syslogd 4513 46082 1 0 3 0x100082 netio syslogd 11705 352925 1 77 3 0x100090 poll dhclient 24516 448681 1 0 3 0x80 poll dhclient 75482 80555 0 0 3 0x14200 bored smr 21132 179727 0 0 2 0x14200 zerothread 4475 68616 0 0 3 0x14200 aiodoned aiodoned 19324 475115 0 0 3 0x14200 syncer update 80284 6307 0 0 3 0x14200 cleaner cleaner 78857 100891 0 0 3 0x14200 reaper reaper 404 76773 0 0 3 0x14200 pgdaemon pagedaemon 35730 461589 0 0 3 0x14200 bored crynlk 39233 518678 0 0 3 0x14200 bored crypto 8344 236693 0 0 3 0x40014200 acpi0 acpi0 35607 418385 0 0 3 0x40014200 idle1 44 492044 0 0 3 0x14200 bored softnet 19249 106737 0 0 3 0x14200 bored systqmp 52495 380141 0 0 3 0x14200 bored systq 28151 294290 0 0 3 0x40014200 bored softclock 94908 200455 0 0 3 0x40014200 idle0 1 196270 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 89992 (syz-executor.1) thread 0xffff8000ffffb8c8 (235015) exclusive rrwlock inode r = 0 (0xfffffd806540f918) #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 rrw_enter+0x88 sys/kern/kern_rwlock.c:462 #3 VOP_LOCK+0x4b sys/kern/vfs_vops.c:614 #4 vn_lock+0x6c sys/kern/vfs_vnops.c:575 #5 vn_write+0x11a sys/kern/vfs_vnops.c:411 #6 dofilewritev+0x1ab sys/kern/sys_generic.c:365 #7 sys_write+0x83 sys/kern/sys_generic.c:285 #8 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #8 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:589 #9 Xsyscall+0x128 Process 89992 (syz-executor.1) thread 0xffff8000ffffb3d8 (368010) shared rwlock vmmaplk r = 0 (0xfffffd807effe468) #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+0x120 sys/uvm/uvm_map.c:2463 #4 sys_mlock+0x180 sys/uvm/uvm_mmap.c:772 #5 syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] #5 syscall+0x4a1 sys/arch/amd64/amd64/trap.c:589 #6 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82892098) #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:589 #2 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 9462 6330K 6330K 78643K 10554 0 pcb 13 8K 8K 78643K 13 0 rtable 105 3K 3K 78643K 189 0 ifaddr 39 10K 10K 78643K 39 0 counters 43 33K 33K 78643K 43 0 ioctlops 0 0K 2K 78643K 31 0 iov 0 0K 16K 78643K 482 0 mount 1 1K 1K 78643K 1 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 5K 78643K 3 0 VM map 2 1K 1K 78643K 2 0 sem 12 0K 0K 78643K 69 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1824 197K 290K 78643K 13058 0 file desc 7 21K 33K 78643K 16361 0 proc 48 50K 83K 78643K 365 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 344 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 568 66K 66K 78643K 37109 0 UVM aobj 22 2K 2K 78643K 22 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 3961K 4025K 78643K 34480 0 kqueue 3 4K 4K 78643K 3 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 6 0 0 1 0 1 1 0 8 0 plcache 128 20 0 0 1 0 1 1 0 8 0 rtpcb 96 23 0 21 1 0 1 1 0 8 0 rtentry 112 45 0 1 2 0 2 2 0 8 0 unpcb 120 116 0 108 1 0 1 1 0 8 0 syncache 272 4 0 4 1 1 0 1 0 8 0 tcpqe 32 458 0 458 3 3 0 2 0 8 0 tcpcb 592 16 0 12 1 0 1 1 0 8 0 inpcb 296 48 0 41 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 semapl 112 67 0 57 1 0 1 1 0 8 0 shmpl 112 19 0 0 1 0 1 1 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 19565 0 18167 88 0 88 88 0 8 0 ffsino 272 19565 0 18167 94 0 94 94 0 8 0 nchpl 144 38093 0 36492 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 80783 0 80783 3 2 1 1 0 8 1 percpumem 16 32 0 0 1 0 1 1 0 8 0 scxspl 192 109312 0 109311 12 11 1 7 0 8 0 plimitpl 152 18 0 9 1 0 1 1 0 8 0 sigapl 424 16548 0 16517 4 0 4 4 0 8 0 futexpl 56 78856 0 78856 2 1 1 1 0 8 1 knotepl 112 62 0 42 1 0 1 1 0 8 0 kqueuepl 152 20303 0 20299 1 0 1 1 0 8 0 pipepl 304 627 0 616 5 3 2 2 0 8 1 fdescpl 496 16533 0 16517 3 0 3 3 0 8 0 filepl 152 46547 0 46445 12 7 5 5 0 8 1 lockfpl 104 12 0 11 1 0 1 1 0 8 0 lockfspl 48 6 0 5 1 0 1 1 0 8 0 sessionpl 120 17 0 7 1 0 1 1 0 8 0 pgrppl 48 18 0 8 1 0 1 1 0 8 0 ucredpl 96 78 0 69 1 0 1 1 0 8 0 zombiepl 144 16517 0 16516 2 1 1 1 0 8 0 processpl 1008 16548 0 16516 5 0 5 5 0 8 0 procpl 632 33505 0 33463 4 0 4 4 0 8 0 sockpl 400 190 0 173 8 5 3 3 0 8 1 mcl64k 65536 20 0 0 3 0 3 3 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 18 0 0 2 0 2 2 0 8 0 mcl9k 9216 4 0 0 1 0 1 1 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 17 0 0 2 0 2 2 0 8 0 mcl2k 2048 315 0 0 38 3 35 38 0 8 0 mtagpl 96 1 0 0 1 0 1 1 0 8 0 mbufpl 256 559 0 0 24 0 24 24 0 8 0 bufpl 280 20454 0 14206 447 0 447 447 0 8 0 anonpl 16 1091167 0 1006890 393 2 391 391 0 124 0 amapchunkpl 152 56090 0 52524 153 1 152 152 0 158 0 amappl16 192 29084 0 26895 110 0 110 110 0 8 0 amappl15 184 3 0 1 1 0 1 1 0 8 0 amappl14 176 23 0 18 1 0 1 1 0 8 0 amappl13 168 8124 0 8121 1 0 1 1 0 8 0 amappl12 160 19 0 14 1 0 1 1 0 8 0 amappl11 152 43 0 33 1 0 1 1 0 8 0 amappl10 144 8241 0 8235 1 0 1 1 0 8 0 amappl9 136 368 0 366 1 0 1 1 0 8 0 amappl8 128 133 0 95 2 0 2 2 0 8 0 amappl7 120 218 0 209 1 0 1 1 0 8 0 amappl6 112 8291 0 8277 1 0 1 1 0 8 0 amappl5 104 17151 0 17132 1 0 1 1 0 8 0 amappl4 96 261 0 234 1 0 1 1 0 8 0 amappl3 88 8193 0 8184 1 0 1 1 0 8 0 amappl2 80 115538 0 115474 2 0 2 2 0 8 0 amappl1 72 500909 0 500414 23 13 10 18 0 8 0 amappl 80 34212 0 33691 11 0 11 11 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 21 0 0 1 0 1 1 0 8 0 uaddrrnd 24 16533 0 16517 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 16533 0 16517 1 0 1 1 0 8 0 vmmpekpl 168 62186 0 62158 3 1 2 2 0 8 0 vmmpepl 168 2127561 0 2123590 293 114 179 274 0 357 6 vmsppl 368 16532 0 16517 2 0 2 2 0 8 0 pdppl 4096 33073 0 33034 6 0 6 6 0 8 0 pvpl 32 4616200 0 4528752 807 2 805 806 0 265 0 pmappl 232 16532 0 16517 2 1 1 2 0 8 0 extentpl 40 53 0 36 1 0 1 1 0 8 0 phpool 112 292 0 13 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(ffffffff82704ff0) 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(ffffffff82891e90) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82891e90) at __mp_lock+0x122 sys/kern/kern_lock.c:147 intr_handler(ffff8000234f21d0,ffff80000065bd80) at intr_handler+0x5e sys/arch/amd64/amd64/intr.c:532 Xintr_ioapic_edge4_untramp() at Xintr_ioapic_edge4_untramp+0x19f __mp_lock(ffffffff82891e90) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82891e90) at __mp_lock+0x122 sys/kern/kern_lock.c:147 intr_handler(ffff8000234f2320,ffff80000004a400) at intr_handler+0x5e sys/arch/amd64/amd64/intr.c:532 Xintr_ioapic_edge17_untramp() at Xintr_ioapic_edge17_untramp+0x19f __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x4f sys/dev/kcov.c:149 softintr_dispatch(0) at softintr_dispatch+0x4e sys/arch/amd64/amd64/softintr.c:90 Xsoftclock() at Xsoftclock+0x1f end of kernel end trace frame: 0x7f7ffffd7680, count: -12 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(fffffd806540f918,9,0) at witness_checkorder+0xf5a witness_debugger sys/kern/subr_witness.c:2490 [inline] witness_checkorder(fffffd806540f918,9,0) at witness_checkorder+0xf5a sys/kern/subr_witness.c:1087 rw_enter(fffffd806540f908,81) at rw_enter+0xd4 rrw_enter(fffffd806540f908,81) at rrw_enter+0x88 sys/kern/kern_rwlock.c:462 VOP_LOCK(fffffd8062d490d8,81) at VOP_LOCK+0x4b sys/kern/vfs_vops.c:614 vn_lock(fffffd8062d490d8,81) at vn_lock+0x6c sys/kern/vfs_vnops.c:575 uvn_io(fffffd807865a768,ffff800025722068,1,2,0) at uvn_io+0x2b5 sys/uvm/uvm_vnode.c:1196 uvn_get(fffffd807865a768,0,ffff8000257222c0,ffff80002572225c,0,5) at uvn_get+0x226 sys/uvm/uvm_vnode.c:1056 uvm_fault(fffffd807effe450,20000000,2,5) at uvm_fault+0x1197 sys/uvm/uvm_fault.c:1016 uvm_fault_wire(fffffd807effe450,20000000,20004000,5) at uvm_fault_wire+0x63 sys/uvm/uvm_fault.c:1285 uvm_map_pageable_wire(fffffd807effe450,fffffd8079265750,fffffd8079265b40,231,ffffffff81a80d0e,0) at uvm_map_pageable_wire+0x30d sys/uvm/uvm_map.c:2367 sys_mlock(ffff8000ffffb3d8,ffff8000257224a8,ffff8000257224f0) at sys_mlock+0x180 sys/uvm/uvm_mmap.c:772 syscall(ffff800025722570) at syscall+0x4a1 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800025722570) at syscall+0x4a1 sys/arch/amd64/amd64/trap.c:589 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xdacaf106eb0, count: -14