*cpu0: uvm_fault(0xfffffd806c44d9a8, 0x0, 0, 1) -> e ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x77b601e147c0, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80003c443b50 rbx 0 rdx 0 rcx 0xffff80003c42da20 rax 0x3b r8 0xffff80003c443a80 r9 0 r10 0x78f2d96b4d1cda13 r11 0x33968bc46e1b81c8 r12 0 r13 0 r14 0xffff80003c42da20 r15 0 rip 0xffffffff82a143ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80003c443ad0 ss 0x10 savectx+0xae: movl $0,%gs:0x688 ddb{1}> show proc PROC (syz-executor) tid=152306 pid=52521 tcnt=4 stat=onproc flags process=0 proc=0 runpri=36, usrpri=84, slppri=36, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff800037409778,0xffff80003c42cd38 process=0xffff80003c4df048 user=0xffff80003c43e000, vmspace=0xfffffd806c44d9a8 estcpu=34, cpticks=11, pctcpu=0.8, user=9, sys=2, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND *52521 152306 396 0 7 0 syz-executor 52521 455169 396 0 3 0x4000080 fsleep syz-executor 52521 40307 396 0 3 0x4000080 fsleep syz-executor 52521 119905 396 0 7 0x4000000 syz-executor 92422 389827 10216 0 3 0x80 nanoslp syz-executor 92422 117599 10216 0 3 0x4000080 ttyin syz-executor 92422 90202 10216 0 3 0x4000080 fsleep syz-executor 92422 517771 10216 0 3 0x4000080 fsleep syz-executor 89108 381203 53583 0 3 0x90 nanoslp syz-executor 89108 159836 53583 0 3 0x4000090 kqpoll syz-executor 89108 235453 53583 0 3 0x4000090 sbwait syz-executor 89108 217060 53583 0 3 0x4000090 fsleep syz-executor 35544 10796 15880 0 2 0xc80 syz-executor 35544 460447 15880 0 3 0x4000080 fifor syz-executor 35544 37166 15880 0 3 0x4000080 fsleep syz-executor 35544 272021 15880 0 3 0x4000080 fsleep syz-executor 40040 432043 23266 0 2 0xc80 syz-executor 40040 484325 23266 0 3 0x4000080 kqread syz-executor 40040 515992 23266 0 3 0x4000080 fsleep syz-executor 396 187477 21415 0 3 0x82 nanoslp syz-executor 53583 209000 21415 0 2 0xc82 syz-executor 88837 338109 21415 0 2 0x2 syz-executor 64550 197504 21415 0 2 0x2 syz-executor 10216 307238 21415 0 3 0x82 nanoslp syz-executor 15880 171779 21415 0 3 0x82 nanoslp syz-executor 73783 285028 0 0 3 0x14200 acct acct 47049 340653 1 0 3 0x100083 ttyin getty 16858 366486 21415 0 2 0x2 syz-executor 23266 136340 21415 0 3 0x82 nanoslp syz-executor 21415 50990 20555 0 3 0x82 kqread syz-executor 20555 481567 77460 0 3 0x10008a sigsusp ksh 77460 49434 65060 0 3 0x98 kqread sshd-session 65060 203059 85973 0 3 0x92 kqread sshd-session 85973 93335 1 0 3 0x88 kqread sshd 46215 63791 87582 74 3 0x1100092 bpf pflogd 87582 504433 1 0 3 0x80 sbwait pflogd 26474 358012 35205 73 3 0x1100090 kqread syslogd 35205 354204 1 0 3 0x100082 sbwait syslogd 56222 131322 1 0 3 0x100080 kqread resolvd 8474 158606 39706 77 3 0x100092 kqread dhcpleased 51548 445484 39706 77 3 0x100092 kqread dhcpleased 39706 156841 1 0 3 0x80 kqread dhcpleased 38462 456891 0 0 3 0x14200 pause smr 24320 443107 0 0 2 0x14200 zerothread 20388 115961 0 0 3 0x14200 aiodoned aiodoned 82628 36787 0 0 2 0x14e00 update 78749 424522 0 0 3 0x14200 cleaner cleaner 1043 151266 0 0 3 0x14200 reaper reaper 26956 340952 0 0 3 0x14200 pgdaemon pagedaemon 29290 488971 0 0 3 0x14200 bored viomb 30135 378201 0 0 3 0x40014200 acpi0 acpi0 24874 335848 0 0 3 0x40014200 idle1 47266 265289 0 0 3 0x14200 bored softnet1 68539 157800 0 0 2 0x14200 softnet0 87268 217463 0 0 3 0x14200 smrbar systqmp 48228 152955 0 0 3 0x14200 bored systq 28650 199514 0 0 3 0x14200 tmoslp softclockmp 51920 147443 0 0 3 0x40014200 tmoslp softclock 40300 493879 0 0 3 0x40014200 idle0 1 376554 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &pmap->pm_mtx r = 0 (0xfffffd806c213c10) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 mtx_enter_try+0x1ad sys/kern/kern_lock.c:311 #2 mtx_enter+0x62 sys/kern/kern_lock.c:261 #3 pmap_write_protect+0x80 rcr3 sys/arch/amd64/compile/SYZKALLER/obj/machine/cpufunc.h:139 [inline] #3 pmap_write_protect+0x80 pmap_map_ptes sys/arch/amd64/amd64/pmap.c:437 [inline] #3 pmap_write_protect+0x80 sys/arch/amd64/amd64/pmap.c:2163 #4 uvm_map_protect+0xb95 pmap_protect sys/arch/amd64/compile/SYZKALLER/obj/machine/pmap.h:476 [inline] #4 uvm_map_protect+0xb95 sys/uvm/uvm_map.c:3191 #5 sys_mprotect+0x351 sys/uvm/uvm_mmap.c:590 #6 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #6 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:765 #7 Xsyscall+0x128 Process 52521 (syz-executor) thread 0xffff80003c42da20 (152306) Process 52521 (syz-executor) thread 0xffff8000fffee018 (119905) Process 64550 (syz-executor) thread 0xffff8000fffef240 (197504) Process 16858 (syz-executor) thread 0xffff80003c42d258 (366486) Process 87268 (systqmp) thread 0xffff8000ffffe000 (217463) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10262 11337K 11505K 166960K 15017 0 pcb 18 16K 18K 166960K 596 0 rtable 234 14K 15K 166960K 1217 0 pf 41 18K 80K 166960K 344 0 ifaddr 39 8K 9K 166960K 252 0 ifgroup 64 2K 3K 166960K 426 0 sysctl 4 1K 9K 166960K 66 0 counters 72 37K 38K 166960K 576 0 ioctlops 0 0K 4K 166960K 2275 0 iov 0 0K 16K 166960K 224 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1424 90K 90K 166960K 3869 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 3 5K 9K 166960K 29 0 VM map 2 1K 1K 166960K 2 0 sem 21 137K 137K 166960K 49 0 dirhash 12 2K 2K 166960K 81 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 16 57K 110K 166960K 3088 0 sigio 0 0K 0K 166960K 49 0 proc 72 115K 164K 166960K 1185 0 subproc 72 4K 4K 166960K 199 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 388 0 in_multi 75 5K 7K 166960K 399 0 ether_multi 1 0K 0K 166960K 44 0 mrt 2 0K 0K 166960K 11 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 229 1023K 1023K 166960K 229 0 exec 0 0K 1K 166960K 815 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 5 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 238 159K 174K 166960K 30032 0 UVM aobj 31 22K 22K 166960K 35 0 pinsyscall 41 82K 101K 166960K 4626 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 250 0 NDP 14 0K 2K 166960K 184 0 temp 79 8676K 8836K 166960K 125195 0 kqueue 14 20K 34K 166960K 571 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 26 0 0 1 0 1 1 0 8 0 rtpcb 120 314 0 310 2 1 1 2 0 8 0 rtentry 176 341 0 258 6 1 5 6 0 8 0 unpcb 144 1950 0 1929 18 16 2 6 0 8 1 syncache 336 11 0 11 7 7 0 1 0 8 0 tcpqe 32 2 0 2 2 2 0 1 0 8 0 tcpcb 736 925 0 920 16 15 1 7 0 8 0 arp 136 56 0 42 1 0 1 1 0 8 0 inpcb 328 2991 0 2981 35 28 7 12 0 8 5 nd6 152 73 0 55 2 0 2 2 0 8 0 pkpcb 40 19 0 19 6 6 0 1 0 8 0 kcovpl 48 22 0 14 1 0 1 1 0 8 0 ppxss 1192 208 0 208 3 2 1 1 0 8 1 pppxif 1504 15 0 15 8 7 1 1 0 8 1 pffrag 232 63 0 51 1 0 1 1 0 482 0 pffrnode 88 25 0 15 1 0 1 1 0 8 0 pffrent 40 121 0 108 1 0 1 1 0 8 0 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 39 0 39 3 2 1 1 0 8 1 pfstitem 24 191 0 102 1 0 1 1 0 8 0 pfstkey 128 191 0 102 3 0 3 3 0 8 0 pfstate 448 191 0 102 10 0 10 10 0 8 0 pfrule 1344 21 0 16 2 1 1 2 0 8 0 rttmr 136 2 0 2 2 2 0 1 0 8 0 art_heap8 4096 6 0 0 6 0 6 6 0 8 0 art_heap4 256 1479 0 1057 42 15 27 30 0 8 0 art_table 40 1485 0 1057 5 0 5 5 0 8 0 art_node 32 340 0 266 1 0 1 1 0 8 0 sysvmsgpl 40 18 0 13 1 0 1 1 0 8 0 semupl 112 2 0 2 2 2 0 1 0 8 0 semapl 112 44 0 25 1 0 1 1 0 8 0 shmpl 112 22 0 3 1 0 1 1 0 8 0 dirhash 1024 63 0 46 3 0 3 3 0 8 0 dino2pl 256 6938 0 5404 97 0 97 97 0 8 0 ffsino 296 6938 0 5404 119 0 119 119 0 8 0 nchpl 144 10939 0 9200 65 0 65 65 0 8 0 rtmask 32 23 0 23 9 8 1 1 0 8 1 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 37902 0 37900 6 5 1 3 0 8 0 percpumem 16 303 0 252 1 0 1 1 0 8 0 vcpupl 3968 9 0 0 2 0 2 2 0 8 0 vmpool 840 10 0 1 1 0 1 1 0 8 0 kstatmem 264 284 0 252 5 2 3 3 0 8 0 acpiwqpl 32 1 0 1 1 0 1 1 1 8 1 scsiplug 72 11 0 11 5 4 1 1 0 8 1 scxspl 216 57986 0 57986 16 15 1 7 1 8 1 plimitpl 152 778 0 760 1 0 1 1 0 8 0 sigapl 424 3400 0 3353 8 1 7 8 0 8 0 knotepl 120 868 0 0 24 0 24 24 0 8 0 kqueuepl 224 1278 0 1265 20 19 1 7 0 8 0 pipepl 344 426 0 399 3 0 3 3 0 8 0 fdescpl 528 3354 0 3324 3 0 3 3 0 8 0 filepl 160 20875 0 20644 33 19 14 17 0 8 2 lockfpl 104 988 0 986 2 1 1 2 0 8 0 lockfspl 48 401 0 399 1 0 1 1 0 8 0 sessionpl 144 43 0 34 1 0 1 1 0 8 0 pgrppl 48 176 0 159 1 0 1 1 0 8 0 ucredpl 104 3168 0 3154 1 0 1 1 0 8 0 zombiepl 144 4623 0 4623 3 2 1 1 0 8 1 processpl 1232 3400 0 3353 6 2 4 6 0 8 0 procpl 664 8389 0 8328 8 2 6 8 0 8 0 sosppl 176 19 0 19 7 6 1 1 0 8 1 sockpl 752 5498 0 5462 60 49 11 17 0 8 7 mcl64k 65536 7 0 0 1 0 1 1 0 8 0 mcl16k 16384 4 0 0 1 0 1 1 0 8 0 mcl12k 12288 3 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 128 0 0 16 0 16 16 0 8 0 mcl2k 2048 63 0 0 6 0 6 6 0 8 0 mtagpl 96 67 0 0 2 0 2 2 0 8 0 mbufpl 256 1889 0 0 111 0 111 111 0 8 0 bufpl 280 22097 0 15960 439 0 439 439 0 8 0 anonpl 32 13439 0 0 108 0 108 108 0 246 0 amapchunkpl 152 105577 0 105111 66 37 29 34 0 158 7 amappl16 200 9186 0 9153 100 80 20 34 0 8 10 amappl15 192 5 0 5 2 2 0 1 0 8 0 amappl14 184 4 0 4 1 1 0 1 0 8 0 amappl13 176 616 0 615 1 0 1 1 0 8 0 amappl12 168 3829 0 3788 3 0 3 3 0 8 0 amappl11 160 3 0 3 1 1 0 1 0 8 0 amappl10 152 48 0 33 1 0 1 1 0 8 0 amappl9 144 250 0 250 1 1 0 1 0 8 0 amappl8 136 31 0 29 1 0 1 1 0 8 0 amappl7 128 143 0 142 1 0 1 1 0 8 0 amappl6 120 459 0 445 1 0 1 1 0 8 0 amappl5 112 76 0 65 1 0 1 1 0 8 0 amappl4 104 530 0 498 1 0 1 1 0 8 0 amappl3 96 18288 0 18201 4 1 3 3 0 8 0 amappl2 88 3487 0 3410 2 0 2 2 0 8 0 amappl1 80 24189 0 23610 15 1 14 14 0 8 0 amappl 88 28535 0 28374 5 0 5 5 0 92 0 uvmvnodes 80 189 0 0 4 0 4 4 0 8 0 dma65536 65536 2 0 2 2 2 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 2 0 2 2 2 0 1 0 8 0 dma256 256 8 0 8 2 2 0 1 0 8 0 dma128 128 255 0 255 3 2 1 1 0 8 1 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 19 0 18 1 0 1 1 0 8 0 aobjpl 72 34 0 4 1 0 1 1 0 8 0 uaddrrnd 24 3354 0 3324 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3354 0 3324 1 0 1 1 0 8 0 vmmpekpl 168 25467 0 25404 4 0 4 4 0 8 0 vmmpepl 168 215806 0 213927 143 39 104 106 0 357 4 vmsppl 488 3353 0 3324 5 0 5 5 0 8 0 rwobjpl 80 55426 0 54283 43 10 33 36 0 8 0 pdppl 4096 6735 0 6659 157 77 80 83 0 8 4 pvpl 32 20061 0 0 161 0 161 161 0 265 0 pmappl 256 3363 0 3325 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 492 0 127 11 0 11 11 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8380aff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 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:670 comcnputc(800,75) at comcnputc+0x250 comcn_read_reg sys/dev/ic/com.c:1655 [inline] comcnputc(800,75) at comcnputc+0x250 sys/dev/ic/com.c:1269 cnputc(75) at cnputc+0x67 sys/dev/cons.c:218 kputchar(75,5,0) at kputchar+0x2ed sys/kern/subr_prf.c:367 kprintf() at kprintf+0x29a5 sys/kern/subr_prf.c:-1 printf(ffffffff83452888) at printf+0x8b sys/kern/subr_prf.c:529 trap_print(ffff80002a2e9b90,6) at trap_print+0x70 sys/arch/amd64/amd64/trap.c:643 kerntrap(ffff80002a2e9b90) at kerntrap+0x2e6 sys/arch/amd64/amd64/trap.c:506 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff80000145d000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:593 dtioctl(11e5f,80044403,ffff80002a2e9ed0,81,ffff8000fffee018) at dtioctl+0x536 sys/dev/dt/dt_dev.c:325 end trace frame: 0xffff80002a2e9db0, count: 0 ddb{0}> trace x86_ipi_db(ffffffff8380aff0) at x86_ipi_db+0x27 sys/arch/amd64/amd64/db_interface.c:394 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:670 comcnputc(800,75) at comcnputc+0x250 comcn_read_reg sys/dev/ic/com.c:1655 [inline] comcnputc(800,75) at comcnputc+0x250 sys/dev/ic/com.c:1269 cnputc(75) at cnputc+0x67 sys/dev/cons.c:218 kputchar(75,5,0) at kputchar+0x2ed sys/kern/subr_prf.c:367 kprintf() at kprintf+0x29a5 sys/kern/subr_prf.c:-1 printf(ffffffff83452888) at printf+0x8b sys/kern/subr_prf.c:529 trap_print(ffff80002a2e9b90,6) at trap_print+0x70 sys/arch/amd64/amd64/trap.c:643 kerntrap(ffff80002a2e9b90) at kerntrap+0x2e6 sys/arch/amd64/amd64/trap.c:506 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff80000145d000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:593 dtioctl(11e5f,80044403,ffff80002a2e9ed0,81,ffff8000fffee018) at dtioctl+0x536 sys/dev/dt/dt_dev.c:325 VOP_IOCTL(fffffd8065d95be8,80044403,ffff80002a2e9ed0,81,fffffd80097fd208,ffff8000fffee018) at VOP_IOCTL+0xac sys/kern/vfs_vops.c:264 vn_ioctl(fffffd806c3c8718,80044403,ffff80002a2e9ed0,ffff8000fffee018) at vn_ioctl+0xf8 sys/kern/vfs_vnops.c:531 sys_ioctl(ffff8000fffee018,ffff80002a2ea0b0,ffff80002a2ea000) at sys_ioctl+0x674 sys/kern/sys_generic.c:-1 syscall(ffff80002a2ea0b0) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a2ea0b0) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:765 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x63e0dbe4a80, count: -19 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x688 savectx() at savectx+0xae end of kernel end trace frame: 0x77b601e147c0, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x77b601e147c0, count: -1