*cpu0: uvm_fault(0xffffffff8353da28, 0xffff800012c72004, 0, 1) -> d ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x9d0a291f790, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80002a0a6360 rbx 0 rdx 0 rcx 0xffff8000ffffd1c8 rax 0x3b r8 0xffff80002a0a6290 r9 0xffff80002a0a612c r10 0x13dcb6bfa767c255 r11 0x617e3067a63b9c18 r12 0 r13 0 r14 0xffff8000ffffd1c8 r15 0 rip 0xffffffff824553ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80002a0a62e0 ss 0x10 savectx+0xae: movl $0,%gs:0x680 ddb{1}> show proc PROC (syz-executor) tid=76875 pid=44958 tcnt=3 stat=onproc flags process=0 proc=4000000 runpri=32, usrpri=50, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000ffffc7a8,0xffff80002c35d488 process=0xffff80002c220008 user=0xffff80002a0a1000, vmspace=0xfffffd806c60a6f8 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 44958 282063 74237 0 2 0 syz-executor *44958 76875 74237 0 7 0x4000000 syz-executor 44958 182055 74237 0 3 0x4000080 fsleep syz-executor 69799 376595 88878 0 2 0 syz-executor 69799 449466 88878 0 7 0x4000000 syz-executor 94250 466533 61135 0 2 0x480 syz-executor 94250 440719 61135 0 3 0x4000080 kqsel syz-executor 94250 289965 61135 0 3 0x4000080 fsleep syz-executor 21713 14660 26938 60928 2 0x490 syz-executor 21713 210625 26938 60928 3 0x4000090 kqsel syz-executor 21713 115798 26938 60928 3 0x4000090 fsleep syz-executor 21713 284822 26938 60928 3 0x4000090 fsleep syz-executor 79491 466709 65277 0 3 0x80 nanoslp syz-executor 79491 457332 65277 0 3 0x4000080 msgwait syz-executor 79491 333526 65277 0 3 0x4000080 fsleep syz-executor 27908 190946 74696 0 2 0x480 syz-executor 27908 96390 74696 0 3 0x4000080 kqsel syz-executor 26938 422806 42263 0 2 0x482 syz-executor 65552 190521 42263 0 2 0x482 syz-executor 65277 147191 42263 0 2 0x482 syz-executor 74696 257422 42263 0 2 0x482 syz-executor 74750 470131 42263 0 2 0x482 syz-executor 74237 20190 42263 0 3 0x82 nanoslp syz-executor 61135 86378 42263 0 2 0x482 syz-executor 88878 294360 42263 0 3 0x82 nanoslp syz-executor 54161 145058 1 0 3 0x100083 ttyopn getty 51259 214855 0 0 3 0x14200 bored sosplice 41106 485846 0 0 3 0x14280 nfsidl nfsio 95980 236744 0 0 3 0x14280 nfsidl nfsio 52960 250704 0 0 3 0x14280 nfsidl nfsio 14990 225269 0 0 3 0x14280 nfsidl nfsio 87540 175741 0 0 3 0x14280 nfsidl nfsio 11831 449555 0 0 3 0x14280 nfsidl nfsio 45327 143129 0 0 3 0x14280 nfsidl nfsio 77728 235248 0 0 3 0x14280 nfsidl nfsio 74120 477969 0 0 3 0x14280 nfsidl nfsio 41920 248446 0 0 3 0x14280 nfsidl nfsio 32929 129137 0 0 3 0x14280 nfsidl nfsio 45831 250076 0 0 3 0x14280 nfsidl nfsio 64521 498327 0 0 3 0x14280 nfsidl nfsio 81046 300771 0 0 3 0x14280 nfsidl nfsio 6972 159104 0 0 3 0x14280 nfsidl nfsio 87677 21897 0 0 3 0x14280 nfsidl nfsio 16587 385798 0 0 3 0x14280 nfsidl nfsio 19327 489976 0 0 3 0x14280 nfsidl nfsio 19829 371946 0 0 3 0x14280 nfsidl nfsio 19101 236852 0 0 3 0x14280 nfsidl nfsio 42263 486640 3792 0 3 0x82 kqread syz-executor 3792 260726 76181 0 3 0x10008a sigsusp ksh 76181 220503 12717 0 3 0x98 kqread sshd-session 12717 73984 79131 0 3 0x92 kqread sshd-session 79131 150640 1 0 3 0x88 kqread sshd 52172 168583 10796 74 3 0x1100092 bpf pflogd 10796 219869 1 0 3 0x80 sbwait pflogd 30186 162331 96736 73 3 0x1100090 kqread syslogd 96736 480325 1 0 3 0x100082 sbwait syslogd 90598 170898 1 0 3 0x100080 kqread resolvd 12572 438303 23710 77 3 0x100092 kqread dhcpleased 12026 130960 23710 77 3 0x100092 kqread dhcpleased 23710 119603 1 0 3 0x80 kqread dhcpleased 39071 304975 0 0 3 0x14200 bored smr 70885 18810 0 0 3 0x14200 pgzero zerothread 15282 294647 0 0 3 0x14200 aiodoned aiodoned 22478 121206 0 0 3 0x14200 syncer update 51399 448633 0 0 3 0x14200 cleaner cleaner 26456 176345 0 0 3 0x14200 reaper reaper 21558 270002 0 0 3 0x14200 pgdaemon pagedaemon 26069 80117 0 0 3 0x14200 bored viomb 94659 489268 0 0 3 0x40014200 acpi0 acpi0 76031 229473 0 0 3 0x40014200 idle1 62881 63351 0 0 3 0x14200 bored softnet3 95409 421396 0 0 3 0x14200 bored softnet2 69227 263408 0 0 3 0x14200 bored softnet1 73290 133045 0 0 3 0x14200 bored softnet0 96076 216765 0 0 3 0x14200 bored systqmp 99947 405751 0 0 3 0x14200 bored systq 13099 440238 0 0 3 0x14200 tmoslp softclockmp 58420 427180 0 0 2 0x40014200 softclock 97348 348512 0 0 3 0x40014200 idle0 1 432963 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &kq->kq_lock r = 0 (0xfffffd806ec8ad90) #0 witness_lock+0x5b8 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5b8 sys/kern/subr_witness.c:1151 #1 mtx_enter_try+0x178 #2 mtx_enter+0x60 sys/kern/kern_lock.c:239 #3 kqueue_register+0x2b6 sys/kern/kern_event.c:1281 #4 ppollregister_evts+0xca sys/kern/sys_generic.c:1047 #5 ppollregister+0x31b sys/kern/sys_generic.c:1145 #6 doppoll+0x21a sys/kern/sys_generic.c:962 #7 sys_poll+0xd8 #8 syscall+0xbb6 mi_syscall sys/sys/syscall_mi.h:179 [inline] #8 syscall+0xbb6 sys/arch/amd64/amd64/trap.c:577 #9 Xsyscall+0x128 Process 69799 (syz-executor) thread 0xffff8000ffffc7a8 (449466) exclusive rrwlock inode r = 0 (0xfffffd80712a4810) #0 witness_lock+0x5b8 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5b8 sys/kern/subr_witness.c:1151 #1 rw_enter+0x41b sys/kern/kern_rwlock.c:309 #2 rrw_enter+0xbe sys/kern/kern_rwlock.c:464 #3 VOP_LOCK+0xa6 sys/kern/vfs_vops.c:524 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:564 #5 vfs_lookup+0x109 sys/kern/vfs_lookup.c:418 #6 namei+0x7aa sys/kern/vfs_lookup.c:250 #7 sys_chroot+0xb5 change_dir sys/kern/vfs_syscalls.c:839 [inline] #7 sys_chroot+0xb5 sys/kern/vfs_syscalls.c:811 #8 syscall+0xaf8 mi_syscall sys/sys/syscall_mi.h:179 [inline] #8 syscall+0xaf8 sys/arch/amd64/amd64/trap.c:577 #9 Xsyscall+0x128 exclusive kernel_lock &kernel_lock r = 0 (0xffffffff83628520) #0 witness_lock+0x5b8 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5b8 sys/kern/subr_witness.c:1151 #1 syscall+0xad6 mi_syscall sys/sys/syscall_mi.h:179 [inline] #1 syscall+0xad6 sys/arch/amd64/amd64/trap.c:577 #2 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10226 10369K 10682K 166960K 12498 0 pcb 17 14K 16K 166960K 310 0 rtable 242 10K 10K 166960K 1754 0 pf 36 18K 25K 166960K 221 0 ifaddr 44 8K 9K 166960K 232 0 ifgroup 55 2K 2K 166960K 249 0 sysctl 3 0K 0K 166960K 5 0 counters 64 36K 36K 166960K 168 0 ioctlops 0 0K 4K 166960K 1641 0 iov 0 0K 24K 166960K 104 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1385 87K 88K 166960K 2779 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 10K 14K 166960K 19 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 44 0 dirhash 12 2K 2K 166960K 27 0 ACPI 1690 195K 286K 166960K 12418 0 file desc 18 65K 97K 166960K 1686 0 sigio 0 0K 0K 166960K 20 0 proc 73 91K 152K 166960K 1818 0 subproc 104 6K 7K 166960K 650 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 1 0K 0K 166960K 153 0 in_multi 99 7K 7K 166960K 604 0 ether_multi 1 0K 0K 166960K 8 0 mrt 0 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 115 519K 519K 166960K 115 0 exec 0 0K 1K 166960K 1087 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 260 74K 92K 166960K 14769 0 UVM aobj 28 2K 4K 166960K 35 0 pinsyscall 43 86K 103K 166960K 3904 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 74 0 NDP 12 0K 1K 166960K 164 0 temp 67 6821K 6888K 166960K 60858 0 kqueue 15 24K 30K 166960K 157 0 SYN cache 2 16K 16K 166960K 2 0 ddb{1}> show all pools Name Size Requests Fail Releases Pgreq Pgrel Npage Hiwat Minpg Maxpg Idle plcache 128 24 0 0 1 0 1 1 0 8 0 rtpcb 120 212 0 209 1 0 1 1 0 8 0 rtentry 112 616 0 508 5 1 4 4 0 8 0 unpcb 144 1050 0 1028 15 13 2 7 0 8 1 syncache 336 10 0 10 4 3 1 1 0 8 1 sackhl 24 1 0 1 1 0 1 1 0 8 1 tcpqe 32 5 0 5 2 1 1 1 0 8 1 tcpcb 808 420 0 411 14 12 2 7 0 8 0 arp 120 114 0 94 1 0 1 1 0 8 0 ipq 40 1 0 1 1 1 0 1 0 8 0 ipqe 40 3 0 3 1 1 0 1 0 8 0 inpcb 336 1742 0 1723 24 14 10 12 0 8 8 nd6 136 159 0 133 1 0 1 1 0 8 0 pkpcb 40 5 0 5 3 3 0 1 0 8 0 kcovpl 48 50 0 42 1 0 1 1 0 8 0 ppxss 1168 8 0 8 2 1 1 1 0 8 1 pfstscr 40 1 0 1 1 0 1 1 0 8 1 pffrag 232 6 0 6 1 0 1 1 0 482 1 pffrnode 88 6 0 6 1 0 1 1 0 8 1 pffrent 40 101 0 101 1 0 1 1 0 8 1 pfosfp 40 1428 0 1005 5 0 5 5 0 8 0 pfosfpen 112 1428 0 714 21 0 21 21 0 8 0 pfrktable 1344 2 0 1 2 1 1 1 0 8 0 pfanchor 1288 2 0 0 1 0 1 1 0 8 0 pftag 88 4 0 1 1 0 1 1 0 8 0 pfstitem 24 108 0 86 1 0 1 1 0 8 0 pfstkey 128 110 0 88 2 0 2 2 0 8 0 pfstate 376 109 0 87 4 0 4 4 0 8 1 pfrule 1344 44 0 35 2 0 2 2 0 8 1 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 2400 0 1937 37 7 30 30 0 8 1 art_table 32 2402 0 1937 4 0 4 4 0 8 0 art_node 16 615 0 519 1 0 1 1 0 8 0 sysvmsgpl 40 17 0 9 1 0 1 1 0 8 0 semapl 112 39 0 29 1 0 1 1 0 8 0 shmpl 112 32 0 7 2 1 1 1 0 8 0 dirhash 1024 27 0 10 3 0 3 3 0 8 0 dino2pl 256 3493 0 1905 100 0 100 100 0 8 0 ffsino 272 3493 0 1905 107 0 107 107 0 8 0 nchpl 144 5094 0 3348 65 0 65 65 0 8 0 uvmvnodes 80 4525 0 0 93 0 93 93 0 8 0 vnodes 216 4525 0 0 252 0 252 252 0 8 0 namei 1024 20668 0 20667 4 3 1 2 0 8 0 percpumem 16 98 0 52 1 0 1 1 0 8 0 kstatmem 264 128 0 104 2 0 2 2 0 8 0 scsiplug 72 1 0 1 1 1 0 1 0 8 0 scxspl 216 29277 0 29277 13 10 3 8 1 8 3 plimitpl 152 423 0 404 1 0 1 1 0 8 0 sigapl 424 1939 0 1868 10 1 9 9 0 8 0 futexpl 64 14917 0 14912 4 3 1 1 0 8 0 knotepl 120 615 0 0 17 0 17 17 0 8 0 kqueuepl 216 283 0 268 4 2 2 3 0 8 1 pipepl 320 446 0 419 11 8 3 8 0 8 0 fdescpl 496 1900 0 1868 7 2 5 6 0 8 0 filepl 152 10638 0 10370 34 19 15 21 0 8 4 lockfpl 104 428 0 426 2 1 1 2 0 8 0 lockfspl 48 136 0 134 1 0 1 1 0 8 0 sessionpl 144 70 0 61 1 0 1 1 0 8 0 pgrppl 48 139 0 122 1 0 1 1 0 8 0 ucredpl 104 1837 0 1822 1 0 1 1 0 8 0 zombiepl 144 1870 0 1868 1 0 1 1 0 8 0 processpl 1160 1939 0 1868 7 1 6 6 0 8 0 procpl 648 3479 0 3397 8 0 8 8 0 8 0 srpgc 96 4 0 4 2 2 0 1 0 8 0 sosppl 168 4 0 4 3 2 1 1 0 8 1 sockpl 664 3014 0 2971 49 38 11 20 0 8 6 mcl64k 65536 5 0 0 1 0 1 1 0 8 0 mcl16k 16384 5 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 7 0 0 1 0 1 1 0 8 0 mcl4k 4096 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 256 0 0 32 0 32 32 0 8 0 mtagpl 96 205 0 0 5 0 5 5 0 8 0 mbufpl 256 518 0 0 28 0 28 28 0 8 0 bufpl 280 8377 0 1999 456 0 456 456 0 8 0 anonpl 24 289654 0 284441 74 19 55 65 0 185 2 amapchunkpl 152 46087 0 45464 53 17 36 36 0 158 10 amappl16 200 6052 0 5998 42 27 15 22 0 8 8 amappl15 192 44 0 44 1 1 0 1 0 8 0 amappl14 184 230 0 218 1 0 1 1 0 8 0 amappl13 176 18 0 18 1 1 0 1 0 8 0 amappl12 168 3220 0 3188 3 1 2 2 0 8 0 amappl11 160 94 0 80 1 0 1 1 0 8 0 amappl10 152 10 0 10 1 1 0 1 0 8 0 amappl9 144 130 0 130 1 1 0 1 0 8 0 amappl8 136 24 0 21 1 0 1 1 0 8 0 amappl7 128 198 0 185 1 0 1 1 0 8 0 amappl6 120 583 0 581 1 0 1 1 0 8 0 amappl5 112 306 0 294 1 0 1 1 0 8 0 amappl4 104 468 0 448 1 0 1 1 0 8 0 amappl3 96 9365 0 9241 5 1 4 4 0 8 0 amappl2 88 1328 0 1259 2 0 2 2 0 8 0 amappl1 80 16148 0 15585 16 2 14 14 0 8 0 amappl 88 13964 0 13768 5 0 5 5 0 92 0 dma65536 65536 1 0 1 1 1 0 1 0 8 0 dma16384 16384 1 0 1 1 1 0 1 0 8 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 dma512 512 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 72 34 0 7 1 0 1 1 0 8 0 uaddrrnd 24 1900 0 1868 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 1900 0 1868 1 0 1 1 0 8 0 vmmpekpl 168 17343 0 17287 4 0 4 4 0 8 0 vmmpepl 168 123904 0 121944 107 16 91 96 0 357 2 vmsppl 440 1899 0 1868 6 2 4 5 0 8 0 rwobjpl 56 40764 0 35228 79 1 78 78 0 8 0 pdppl 4096 3807 0 3736 173 100 73 87 0 8 2 pvpl 32 29793 0 0 240 0 240 240 0 265 0 pmappl 248 1899 0 1868 3 0 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 540 0 145 12 0 12 12 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff834f4ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x37 sys/arch/amd64/amd64/bus_space.c:654 comcnputc(800,2d) at comcnputc+0x250 comcn_read_reg sys/dev/ic/com.c:1655 [inline] comcnputc(800,2d) at comcnputc+0x250 sys/dev/ic/com.c:1269 cnputc(2d) at cnputc+0x61 sys/dev/cons.c:218 db_putchar(2d) at db_putchar+0x65c sys/ddb/db_output.c:155 kprintf() at kprintf+0x2aba sys/kern/subr_prf.c:1065 db_printf(ffffffff8309367f) at db_printf+0x9b fault(ffffffff8303e9bb) at fault+0xa7 sys/arch/amd64/amd64/trap.c:157 kpageflttrap(ffff80002a0a0870,ffff800012c72004) at kpageflttrap+0x385 sys/arch/amd64/amd64/trap.c:290 kerntrap(ffff80002a0a0870) at kerntrap+0x14a sys/arch/amd64/amd64/trap.c:332 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b ufs_lookup() at ufs_lookup+0x5e1 sys/ufs/ufs/ufs_lookup.c:279 end trace frame: 0xffff80002a0a0aa0, count: 0 ddb{0}> trace x86_ipi_db(ffffffff834f4ff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:393 x86_ipi_handler() at x86_ipi_handler+0xd9 sys/arch/amd64/amd64/ipi.c:106 Xresume_lapic_ipi() at Xresume_lapic_ipi+0x27 x86_bus_space_io_read_1(3f8,5) at x86_bus_space_io_read_1+0x37 sys/arch/amd64/amd64/bus_space.c:654 comcnputc(800,2d) at comcnputc+0x250 comcn_read_reg sys/dev/ic/com.c:1655 [inline] comcnputc(800,2d) at comcnputc+0x250 sys/dev/ic/com.c:1269 cnputc(2d) at cnputc+0x61 sys/dev/cons.c:218 db_putchar(2d) at db_putchar+0x65c sys/ddb/db_output.c:155 kprintf() at kprintf+0x2aba sys/kern/subr_prf.c:1065 db_printf(ffffffff8309367f) at db_printf+0x9b fault(ffffffff8303e9bb) at fault+0xa7 sys/arch/amd64/amd64/trap.c:157 kpageflttrap(ffff80002a0a0870,ffff800012c72004) at kpageflttrap+0x385 sys/arch/amd64/amd64/trap.c:290 kerntrap(ffff80002a0a0870) at kerntrap+0x14a sys/arch/amd64/amd64/trap.c:332 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b ufs_lookup() at ufs_lookup+0x5e1 sys/ufs/ufs/ufs_lookup.c:279 VOP_LOOKUP(fffffd80750706e0,ffff80002a0a0c18,ffff80002a0a0c48) at VOP_LOOKUP+0x6e sys/kern/vfs_vops.c:85 vfs_lookup(ffff80002a0a0be8) at vfs_lookup+0x8fa sys/kern/vfs_lookup.c:566 namei(ffff80002a0a0be8) at namei+0x7aa sys/kern/vfs_lookup.c:250 sys_chroot(ffff8000ffffc7a8,ffff80002a0a0dc0,ffff80002a0a0d10) at sys_chroot+0xb5 change_dir sys/kern/vfs_syscalls.c:839 [inline] sys_chroot(ffff8000ffffc7a8,ffff80002a0a0dc0,ffff80002a0a0d10) at sys_chroot+0xb5 sys/kern/vfs_syscalls.c:811 syscall(ffff80002a0a0dc0) at syscall+0xaf8 mi_syscall sys/sys/syscall_mi.h:179 [inline] syscall(ffff80002a0a0dc0) at syscall+0xaf8 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xc609286a350, count: -20 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x680 savectx() at savectx+0xae end of kernel end trace frame: 0x9d0a291f790, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x9d0a291f790, count: -1