witness: lock order reversal: 1st 0xfffffd806afb5438 fdlock (&newfdp->fd_fd.fd_lock) 2nd 0xfffffd8064490a30 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(fffffd8064490a30,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8064490a30,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd8064490a20,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd8064490a20,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd806994b780,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd806994b780,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8069f09568,0,ffff800023474a78,ffff800023474a48,0,0,38b402bdb78cf79,ffffffff822ced80) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8069f09568,0,ffff800023474a78,ffff800023474a48,0,0,38b402bdb78cf79,ffffffff822ced80) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff800023474be0,ffff800023474c18,ffff800023474b60,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd807effaa10,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff800023474d70,20000080) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff800023474d70) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff800023474fb0) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800023474fb0) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x1dc8b63ea60, count: -15 ddb{1}> show registers rdi 0xffff8000234a2000 rsi 0x77cd __ALIGN_SIZE+0x67cd rbp 0xffff8000234746f0 rbx 0x3 rdx 0xffff8000234a2000 rcx 0x77cc __ALIGN_SIZE+0x67cc rax 0xffffffff81a758b7 db_enter+0x17 r8 0xffffffff81cc307c witness_checkorder+0x10cc r9 0x5 r10 0xe7d872840a014ac2 r11 0x9f144771a746d894 r12 0xfffffd8002dbe880 r13 0 r14 0 r15 0 rip 0xffffffff81a758b8 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff8000234746e0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor.1) pid=489619 stat=onproc flags process=10 proc=4000000 pri=32, usrpri=86, nice=20 forw=0xffffffffffffffff, list=0xffff80002123afc0,0xffff80002123ba50 process=0xffff8000ffff9928 user=0xffff800023470000, vmspace=0xfffffd807effaa10 estcpu=36, cpticks=1, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 89377 15781 56972 32767 7 0x10 syz-executor.0 71532 33988 98161 32767 2 0x10 syz-executor.1 *71532 489619 98161 32767 7 0x4000010 syz-executor.1 56972 497755 90761 32767 3 0x90 nanoslp syz-executor.0 90761 179073 68970 0 3 0x82 wait syz-executor.0 98161 212375 73122 32767 3 0x90 nanoslp syz-executor.1 73122 437372 68970 0 3 0x82 wait syz-executor.1 46439 470063 0 0 3 0x14200 bored sosplice 68970 454234 62461 0 3 0x82 thrsleep syz-fuzzer 68970 209343 62461 0 3 0x4000082 nanoslp syz-fuzzer 68970 269725 62461 0 3 0x4000082 kqread syz-fuzzer 68970 226624 62461 0 3 0x4000082 thrsleep syz-fuzzer 68970 178817 62461 0 3 0x4000082 thrsleep syz-fuzzer 68970 469693 62461 0 3 0x4000082 thrsleep syz-fuzzer 68970 180805 62461 0 3 0x4000082 nanoslp syz-fuzzer 68970 233476 62461 0 3 0x4000082 thrsleep syz-fuzzer 62461 300079 98859 0 3 0x10008a sigsusp ksh 98859 136079 82131 0 3 0x9a select sshd 34839 374735 1 0 3 0x100083 ttyin getty 82131 126003 1 0 3 0x88 select sshd 71151 40707 88977 73 3 0x100090 kqread syslogd 88977 299834 1 0 3 0x100082 netio syslogd 69246 100363 1 0 3 0x100080 kqread resolvd 2475 196390 15059 77 3 0x100092 kqread dhcpleased 39007 16152 15059 77 3 0x100092 kqread dhcpleased 15059 233938 1 0 3 0x80 kqread dhcpleased 50682 2943 0 0 3 0x14200 bored smr 69844 440218 0 0 3 0x14200 pgzero zerothread 88551 514038 0 0 3 0x14200 aiodoned aiodoned 8802 387849 0 0 3 0x14200 syncer update 951 42604 0 0 3 0x14200 cleaner cleaner 14188 389749 0 0 3 0x14200 reaper reaper 22458 442788 0 0 3 0x14200 pgdaemon pagedaemon 50978 110590 0 0 3 0x14200 bored crynlk 51041 516976 0 0 3 0x14200 bored crypto 62751 283500 0 0 3 0x14200 bored viomb 24786 497629 0 0 3 0x40014200 acpi0 acpi0 39032 287854 0 0 3 0x40014200 idle1 44821 69570 0 0 3 0x14200 bored softnet 26347 480532 0 0 3 0x14200 bored systqmp 77422 283964 0 0 3 0x14200 bored systq 76650 204926 0 0 3 0x40014200 bored softclock 90067 457143 0 0 3 0x40014200 idle0 1 516820 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks Process 89377 (syz-executor.0) thread 0xffff80002123ba40 (15781) shared rwlock vmmaplk r = 0 (0xfffffd807effa748) #0 witness_lock+0x4b0 stacktrace_save sys/sys/stacktrace.h:36 [inline] #0 witness_lock+0x4b0 sys/kern/subr_witness.c:1182 #1 uvmfault_lookup+0xd9 sys/uvm/uvm_fault.c:1701 #2 uvm_fault_check+0x3a sys/uvm/uvm_fault.c:674 #3 uvm_fault+0x102 sys/uvm/uvm_fault.c:601 #4 upageflttrap+0x82 sys/arch/amd64/amd64/trap.c:181 #5 usertrap+0x214 sys/arch/amd64/amd64/trap.c:403 #6 recall_trap+0x8 Process 71532 (syz-executor.1) thread 0xffff80002123b260 (489619) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff82985cc8) #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 (0xfffffd806afb5438) #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 10117 6407K 6433K 78643K 11243 0 pcb 13 8K 8K 78643K 13 0 rtable 108 3K 4K 78643K 773 0 ifaddr 39 10K 10K 78643K 129 0 sysctl 2 0K 0K 78643K 2 0 counters 44 34K 34K 78643K 68 0 ioctlops 0 0K 2K 78643K 181 0 iov 0 0K 16K 78643K 319 0 mount 1 1K 1K 78643K 1 0 log 0 0K 0K 78643K 5 0 vnodes 1216 76K 77K 78643K 1544 0 UFS quota 1 32K 32K 78643K 1 0 UFS mount 5 36K 36K 78643K 5 0 shm 2 1K 9K 78643K 48 0 VM map 2 1K 1K 78643K 2 0 sem 10 1K 1K 78643K 23 0 dirhash 12 2K 2K 78643K 12 0 ACPI 1697 195K 286K 78643K 12598 0 file desc 8 25K 33K 78643K 9208 0 sigio 0 0K 0K 78643K 59 0 proc 56 74K 99K 78643K 738 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 614 0 in_multi 33 2K 2K 78643K 343 0 ether_multi 1 0K 0K 78643K 44 0 mrt 1 0K 0K 78643K 1 0 ISOFS mount 1 32K 32K 78643K 1 0 MSDOSFS mount 1 16K 16K 78643K 1 0 ttys 49 228K 228K 78643K 49 0 exec 0 0K 2K 78643K 1313 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 363 48K 53K 78643K 114403 0 UVM aobj 118 3K 3K 78643K 174 0 memdesc 1 4K 4K 78643K 1 0 crypto data 1 1K 1K 78643K 1 0 ip6_options 0 0K 0K 78643K 230 0 NDP 5 0K 0K 78643K 45 0 temp 102 4213K 4325K 78643K 22214 0 kqueue 11 16K 20K 78643K 304 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 120 355 0 352 1 0 1 1 0 8 0 rtentry 112 186 0 141 2 0 2 2 0 8 0 unpcb 120 2429 0 2406 3 2 1 2 0 8 0 syncache 296 100 0 100 10 10 0 1 0 8 0 tcpqe 32 370 0 370 10 10 0 1 0 8 0 tcpcb 736 1605 0 1591 17 15 2 7 0 8 0 arp 120 33 0 27 1 0 1 1 0 8 0 inpcb 304 3358 0 3350 7 6 1 5 0 8 0 rttmr 72 5 0 5 1 1 0 1 0 8 0 ip6q 72 1 0 1 1 1 0 1 0 8 0 ip6af 40 3 0 3 1 1 0 1 0 8 0 nd6 48 47 0 40 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 256 791 0 598 17 4 13 15 0 8 0 art_table 32 792 0 598 2 0 2 2 0 8 0 art_node 16 185 0 144 1 0 1 1 0 8 0 sysvmsgpl 40 10 0 0 1 0 1 1 0 8 0 semupl 112 5 0 5 1 1 0 1 0 8 0 semapl 112 21 0 13 1 0 1 1 0 8 0 shmpl 112 171 0 56 6 2 4 4 0 8 0 dirhash 1024 17 0 0 3 0 3 3 0 8 0 dino2pl 256 11498 0 10090 89 0 89 89 0 8 0 ffsino 272 11498 0 10090 95 0 95 95 0 8 0 nchpl 144 24239 0 22638 61 1 60 61 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 55139 0 55139 1 0 1 1 0 8 1 percpumem 16 46 0 12 1 0 1 1 0 8 0 scxspl 216 67377 0 67377 13 12 1 8 0 8 1 plimitpl 152 193 0 183 1 0 1 1 0 8 0 sigapl 424 9401 0 9365 5 0 5 5 0 8 1 futexpl 56 131355 0 131355 1 0 1 1 0 8 1 knotepl 112 64 0 0 2 0 2 2 0 8 0 kqueuepl 216 13813 0 13799 14 12 2 2 0 8 1 pipepl 336 949 0 938 9 7 2 2 0 8 1 fdescpl 496 9384 0 9365 4 1 3 3 0 8 0 filepl 152 39982 0 39869 13 8 5 7 0 8 0 lockfpl 104 928 0 925 1 0 1 1 0 8 0 lockfspl 48 416 0 413 1 0 1 1 0 8 0 sessionpl 144 29 0 19 1 0 1 1 0 8 0 pgrppl 48 62 0 52 1 0 1 1 0 8 0 ucredpl 96 3064 0 3052 1 0 1 1 0 8 0 zombiepl 144 9365 0 9365 1 0 1 1 0 8 1 processpl 1072 9401 0 9365 3 0 3 3 0 8 0 procpl 672 21056 0 21012 14 10 4 5 0 8 0 sosppl 168 90 0 90 9 9 0 1 0 8 0 sockpl 480 6239 0 6205 18 12 6 8 0 8 0 mcl64k 65536 17 0 0 3 0 3 3 0 8 0 mcl16k 16384 33 0 0 4 1 3 3 0 8 0 mcl12k 12288 17 0 0 2 0 2 2 0 8 0 mcl9k 9216 17 0 0 2 0 2 2 0 8 0 mcl8k 8192 25 0 0 3 0 3 3 0 8 0 mcl4k 4096 29 0 0 4 2 2 3 0 8 0 mcl2k2 2112 11 0 0 1 0 1 1 0 8 0 mcl2k 2048 511 0 0 29 1 28 28 0 8 0 mtagpl 96 2 0 0 1 0 1 1 0 8 0 mbufpl 256 1439 0 0 90 0 90 90 0 8 0 bufpl 280 15886 0 9554 453 0 453 453 0 8 0 anonpl 24 2495492 0 2470251 251 97 154 156 0 186 1 amapchunkpl 152 266800 0 266028 45 14 31 33 0 158 1 amappl16 200 20937 0 19997 125 75 50 56 0 8 0 amappl15 192 542 0 540 1 0 1 1 0 8 0 amappl14 184 11 0 6 1 0 1 1 0 8 0 amappl13 176 240 0 239 1 0 1 1 0 8 0 amappl12 168 29 0 23 1 0 1 1 0 8 0 amappl11 160 38 0 28 1 0 1 1 0 8 0 amappl10 152 3902 0 3893 1 0 1 1 0 8 0 amappl9 144 2489 0 2485 1 0 1 1 0 8 0 amappl8 136 3059 0 2910 7 1 6 6 0 8 0 amappl7 128 2349 0 2332 1 0 1 1 0 8 0 amappl6 120 2620 0 2608 1 0 1 1 0 8 0 amappl5 112 13719 0 13698 1 0 1 1 0 8 0 amappl4 104 1144 0 1111 1 0 1 1 0 8 0 amappl3 96 839 0 837 1 0 1 1 0 8 0 amappl2 88 962 0 906 2 0 2 2 0 8 0 amappl1 80 162187 0 161746 12 2 10 12 0 8 0 amappl 88 110948 0 110736 6 0 6 6 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 64 173 0 56 2 0 2 2 0 8 0 uaddrrnd 24 9384 0 9365 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 9384 0 9365 1 0 1 1 0 8 0 vmmpekpl 168 50545 0 50518 2 0 2 2 0 8 0 vmmpepl 168 1082136 0 1079523 219 103 116 144 0 357 1 vmsppl 368 9383 0 9365 2 0 2 2 0 8 0 rwobjpl 56 189633 0 187827 46 20 26 28 0 8 0 pdppl 4096 18776 0 18730 80 34 46 50 0 8 0 pvpl 32 6190254 0 6161193 405 165 240 244 0 265 5 pmappl 224 9383 0 9365 2 0 2 2 0 8 0 extentpl 40 58 0 40 1 0 1 1 0 8 0 phpool 112 450 0 66 12 0 12 12 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x1a: addq $0x8,%rsp ddb{0}> trace x86_ipi_db(ffffffff82822ff0) 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(ffffffff82985ac0) at __mp_lock+0x133 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82985ac0) 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 __mp_lock(ffffffff82985ac0) at __mp_lock+0x122 __mp_lock_spin sys/kern/kern_lock.c:116 [inline] __mp_lock(ffffffff82985ac0) at __mp_lock+0x122 sys/kern/kern_lock.c:147 uvm_fault(fffffd807effa730,ab0721da000,0,4) at uvm_fault+0x224 sys/uvm/uvm_fault.c:637 upageflttrap(ffff8000254a7440,ab0721dabc0) at upageflttrap+0x82 sys/arch/amd64/amd64/trap.c:181 usertrap(ffff8000254a7440) at usertrap+0x214 sys/arch/amd64/amd64/trap.c:403 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x7f7ffffec530, 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:440 witness_checkorder(fffffd8064490a30,9,0) at witness_checkorder+0x10f3 witness_debugger sys/kern/subr_witness.c:2502 [inline] witness_checkorder(fffffd8064490a30,9,0) at witness_checkorder+0x10f3 sys/kern/subr_witness.c:1105 rw_enter(fffffd8064490a20,81) at rw_enter+0xd1 sys/kern/kern_rwlock.c:250 rrw_enter(fffffd8064490a20,81) at rrw_enter+0x8b sys/kern/kern_rwlock.c:461 VOP_LOCK(fffffd806994b780,81) at VOP_LOCK+0x87 sys/kern/vfs_vops.c:614 vn_lock(fffffd806994b780,81) at vn_lock+0x84 sys/kern/vfs_vnops.c:579 uvn_get(fffffd8069f09568,0,ffff800023474a78,ffff800023474a48,0,0,38b402bdb78cf79,ffffffff822ced80) at uvn_get+0x256 uvm_vnode_lock sys/uvm/uvm_vnode.c:1499 [inline] uvn_get(fffffd8069f09568,0,ffff800023474a78,ffff800023474a48,0,0,38b402bdb78cf79,ffffffff822ced80) at uvn_get+0x256 sys/uvm/uvm_vnode.c:993 uvm_fault_lower(ffff800023474be0,ffff800023474c18,ffff800023474b60,0) at uvm_fault_lower+0x302 sys/uvm/uvm_fault.c:1251 uvm_fault(fffffd807effaa10,20000000,0,2) at uvm_fault+0x240 sys/uvm/uvm_fault.c:638 kpageflttrap(ffff800023474d70,20000080) at kpageflttrap+0x1fd sys/arch/amd64/amd64/trap.c:264 kerntrap(ffff800023474d70) at kerntrap+0xef sys/arch/amd64/amd64/trap.c:318 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b copyout() at copyout+0x53 syscall(ffff800023474fb0) at syscall+0x5a9 mi_syscall sys/sys/syscall_mi.h:102 [inline] syscall(ffff800023474fb0) at syscall+0x5a9 sys/arch/amd64/amd64/trap.c:587 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x1dc8b63ea60, count: -15