witness: lock order reversal: 1st 0xfffffd806f175a10 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd806c46a4e0 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(fffffd806c46a4e0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd806c46a4e0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd806c46a4d0,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd806c46a4d0,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd805d32c398,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd805d32c398,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd80594f28d0,0,ffff8000234ab698,ffff8000234ab668,0,0,883feed257725c90,ffffffff8209a450) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd80594f28d0,0,ffff8000234ab698,ffff8000234ab668,0,0,883feed257725c90,ffffffff8209a450) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000234ab800,ffff8000234ab838,ffff8000234ab780,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd80085962e0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000234ab990,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000234ab990) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000234abbc0) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000234abbc0) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3ff808bf7a0, count: -15 ddb{1}> show registers rdi 0xffff8000234ac000 rsi 0x700b __ALIGN_SIZE+0x600b rbp 0xffff8000234ab310 rbx 0x3 rdx 0xffff8000234ac000 rcx 0x700a __ALIGN_SIZE+0x600a rax 0xffffffff81496317 db_enter+0x17 r8 0xffffffff81860f1c witness_checkorder+0x10cc r9 0x5 r10 0xaad5f3aee53c2851 r11 0xd8a62ef158eccb70 r12 0xfffffd8002dc0900 r13 0 r14 0 r15 0 rip 0xffffffff81496318 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000234ab300 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=171507 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=79, nice=20 forw=0xffffffffffffffff, list=0xffff800021211ce8,0xffff8000212107f8 process=0xffff8000ffffa188 user=0xffff8000234a6000, vmspace=0xfffffd80085962e0 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 39106 353094 56025 32767 2 0x10 syz-executor.0 20688 400320 89985 32767 7 0x10 syz-executor.1 *20688 171507 89985 32767 7 0x4000010 syz-executor.1 89985 523187 12632 32767 3 0x90 nanoslp syz-executor.1 56025 262410 52542 32767 3 0x90 nanoslp syz-executor.0 12632 44567 39206 0 3 0x82 wait syz-executor.1 52542 472419 39206 0 3 0x82 wait syz-executor.0 39206 401612 86770 0 3 0x82 kqread syz-fuzzer 39206 473584 86770 0 3 0x4000082 nanoslp syz-fuzzer 39206 235155 86770 0 3 0x4000082 nanoslp syz-fuzzer 39206 38795 86770 0 3 0x4000082 thrsleep syz-fuzzer 39206 11295 86770 0 3 0x4000082 thrsleep syz-fuzzer 39206 435271 86770 0 3 0x4000082 thrsleep syz-fuzzer 39206 493868 86770 0 3 0x4000082 thrsleep syz-fuzzer 39206 288611 86770 0 3 0x4000082 thrsleep syz-fuzzer 86770 404357 13300 0 3 0x10008a sigsusp ksh 13300 289788 17434 0 3 0x9a select sshd 74572 70447 1 0 3 0x100083 ttyin getty 17434 85243 1 0 3 0x88 select sshd 84724 456822 44366 73 3 0x100090 kqread syslogd 44366 16424 1 0 3 0x100082 netio syslogd 20926 155736 1 0 3 0x100080 kqread resolvd 7781 143914 16695 77 3 0x100092 kqread dhcpleased 61020 315472 16695 77 3 0x100092 kqread dhcpleased 16695 37289 1 0 3 0x80 kqread dhcpleased 37159 260467 0 0 3 0x14200 bored smr 27145 440851 0 0 2 0x14200 zerothread 38213 232075 0 0 3 0x14200 aiodoned aiodoned 3285 343630 0 0 3 0x14200 syncer update 81837 412231 0 0 3 0x14200 cleaner cleaner 57179 75830 0 0 3 0x14200 reaper reaper 88074 40877 0 0 3 0x14200 pgdaemon pagedaemon 82621 251531 0 0 3 0x14200 bored crynlk 5690 154586 0 0 3 0x14200 bored crypto 92655 293182 0 0 3 0x14200 bored viomb 66302 380741 0 0 3 0x40014200 acpi0 acpi0 12906 73454 0 0 3 0x40014200 idle1 87285 10040 0 0 3 0x14200 bored softnet 15453 74203 0 0 3 0x14200 bored systqmp 79665 388826 0 0 3 0x14200 bored systq 59217 114614 0 0 3 0x40014200 bored softclock 19639 261687 0 0 3 0x40014200 idle0 1 515048 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 20688 (syz-executor.1) thread 0xffff800021210548 (171507) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff828d7818) #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 (0xfffffd806f175a10) #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 10113 6407K 6433K 78643K 11203 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 43 0 iov 0 0K 0K 78643K 27 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1216 76K 76K 78643K 1221 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 10 1K 1K 78643K 21 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 8 25K 33K 78643K 43190 0 proc 56 74K 87K 78643K 285 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 372 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 736 84K 85K 78643K 516686 0 UVM aobj 131 4K 4K 78643K 131 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 NDP 5 0K 0K 78643K 9 0 temp 102 4213K 4277K 78643K 88478 0 kqueue 10 14K 18K 78643K 836 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 1231 0 1214 1 0 1 1 0 8 0 syncache 296 4 0 4 1 1 0 1 0 8 0 tcpqe 32 128 0 128 3 3 0 1 0 8 0 tcpcb 736 8 0 4 1 0 1 1 0 8 0 arp 120 6 0 0 1 0 1 1 0 8 0 inpcb 304 47 0 40 2 1 1 2 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 256 188 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 44 0 4 1 0 1 1 0 8 0 sysvmsgpl 40 11 0 0 1 0 1 1 0 8 0 semupl 112 5 0 5 1 1 0 1 0 8 0 semapl 112 8 0 0 1 0 1 1 0 8 0 shmpl 112 128 0 0 4 0 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 48436 0 47032 88 0 88 88 0 8 0 ffsino 272 48436 0 47032 95 1 94 94 0 8 0 nchpl 144 96497 0 94883 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 217531 0 217531 2 1 1 1 0 8 1 percpumem 16 34 0 0 1 0 1 1 0 8 0 scxspl 216 276130 0 276130 12 11 1 8 0 8 1 plimitpl 152 18 0 8 1 0 1 1 0 8 0 sigapl 424 43413 0 43378 5 1 4 5 0 8 0 futexpl 56 275035 0 275035 1 0 1 1 0 8 1 knotepl 112 55 0 0 2 0 2 2 0 8 0 kqueuepl 216 79553 0 79541 6 4 2 2 0 8 1 pipepl 336 285 0 275 8 6 2 2 0 8 1 fdescpl 496 43397 0 43378 3 0 3 3 0 8 0 filepl 152 152340 0 152224 5 0 5 5 0 8 0 lockfpl 104 227 0 225 1 0 1 1 0 8 0 lockfspl 48 109 0 107 1 0 1 1 0 8 0 sessionpl 144 17 0 7 1 0 1 1 0 8 0 pgrppl 48 19 0 9 1 0 1 1 0 8 0 ucredpl 96 1375 0 1363 1 0 1 1 0 8 0 zombiepl 144 43378 0 43378 2 1 1 1 0 8 1 processpl 1072 43413 0 43378 3 0 3 3 0 8 0 procpl 672 87955 0 87912 8 4 4 5 0 8 0 sockpl 480 1847 0 1820 13 9 4 4 0 8 0 mcl64k 65536 18 0 0 3 0 3 3 0 8 0 mcl16k 16384 25 0 0 3 0 3 3 0 8 0 mcl12k 12288 41 0 0 2 0 2 2 0 8 0 mcl9k 9216 26 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 3 0 3 3 0 8 0 mcl4k 4096 25 0 0 4 1 3 3 0 8 0 mcl2k2 2112 13 0 0 1 0 1 1 0 8 0 mcl2k 2048 524 0 0 25 9 16 25 0 8 0 mtagpl 96 3 0 0 1 0 1 1 0 8 0 mbufpl 256 920 0 0 34 6 28 34 0 8 0 bufpl 280 46731 0 40410 452 0 452 452 0 8 0 anonpl 24 10764523 0 10650280 738 5 733 737 0 186 0 amapchunkpl 152 1195914 0 1191213 187 2 185 186 0 158 0 amappl16 200 68927 0 65824 166 2 164 164 0 8 0 amappl15 192 21672 0 21662 1 0 1 1 0 8 0 amappl14 184 2 0 2 2 2 0 1 0 8 0 amappl13 176 21591 0 21587 1 0 1 1 0 8 0 amappl12 168 12 0 9 1 0 1 1 0 8 0 amappl11 160 71 0 56 1 0 1 1 0 8 0 amappl10 152 12 0 10 1 0 1 1 0 8 0 amappl9 144 311 0 306 1 0 1 1 0 8 0 amappl8 136 369 0 312 2 0 2 2 0 8 0 amappl7 128 52 0 44 1 0 1 1 0 8 0 amappl6 120 53 0 44 1 0 1 1 0 8 0 amappl5 112 48862 0 48840 1 0 1 1 0 8 0 amappl4 104 1108 0 1082 1 0 1 1 0 8 0 amappl3 96 2647 0 2631 1 0 1 1 0 8 0 amappl2 88 29155 0 29113 2 1 1 2 0 8 0 amappl1 80 703306 0 702856 13 3 10 12 0 8 0 amappl 88 504482 0 503825 15 0 15 15 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 64 130 0 0 3 0 3 3 0 8 0 uaddrrnd 24 43397 0 43378 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 43397 0 43378 1 0 1 1 0 8 0 vmmpekpl 168 149962 0 149934 2 0 2 2 0 8 0 vmmpepl 168 4879481 0 4874376 379 155 224 368 0 357 2 vmsppl 368 43396 0 43378 2 0 2 2 0 8 0 rwobjpl 56 789021 0 784676 64 2 62 62 0 8 0 pdppl 4096 86802 0 86756 72 26 46 50 0 8 0 pvpl 32 22370680 0 22252803 1015 10 1005 1014 0 265 0 pmappl 224 43396 0 43378 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 359 0 52 11 1 10 11 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff82787ff0) 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(ffffffff828d7610) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff828d7610) 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 __mp_lock(ffffffff828d7610) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff828d7610) at __mp_lock+0x122 sys/kern/kern_lock.c:147 syscall(ffff8000234a5bf0) at syscall+0x42d mi_syscall sys/sys/syscall_mi.h:93 [inline] syscall(ffff8000234a5bf0) at syscall+0x42d sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7f7ffffedd00, 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:440 witness_checkorder(fffffd806c46a4e0,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd806c46a4e0,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd806c46a4d0,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd806c46a4d0,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd805d32c398,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd805d32c398,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd80594f28d0,0,ffff8000234ab698,ffff8000234ab668,0,0,883feed257725c90,ffffffff8209a450) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd80594f28d0,0,ffff8000234ab698,ffff8000234ab668,0,0,883feed257725c90,ffffffff8209a450) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff8000234ab800,ffff8000234ab838,ffff8000234ab780,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd80085962e0,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff8000234ab990,20000040) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff8000234ab990) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff8000234abbc0) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff8000234abbc0) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x3ff808bf7a0, count: -15