*cpu0: uvm_fault(0xfffffd8069ccdd80, 0x0, 0, 1) -> e ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x6f8471442ac0, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80002a3bfba0 rbx 0 rdx 0 rcx 0xffff80003c4822c8 rax 0x3a r8 0xffff80002a3bfad0 r9 0 r10 0x18be667e21340514 r11 0x6533445a8a1f256e r12 0 r13 0 r14 0xffff80003c4822c8 r15 0 rip 0xffffffff813a73ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80002a3bfb20 ss 0x10 savectx+0xae: movl $0,%gs:0x688 ddb{1}> show proc PROC (syz-executor) tid=102148 pid=29828 tcnt=3 stat=onproc flags process=0 proc=0 runpri=86, usrpri=86, slppri=36, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c482fc0,0xffff80003c483cc8 process=0xffff8000ffff79c8 user=0xffff80002a3ba000, vmspace=0xfffffd8069ccd210 estcpu=36, cpticks=9, pctcpu=0.0, user=8, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 73764 128661 86739 0 3 0 kmmaplk syz-executor 69573 507798 18140 0 2 0x2 arp 18140 428361 76449 0 3 0x10008a sigsusp sh *29828 102148 25552 0 7 0 syz-executor 29828 436619 25552 0 3 0x4000080 fsleep syz-executor 29828 322010 25552 0 3 0x4000080 fsleep syz-executor 76449 318313 9168 0 3 0x82 wait syz-executor 86739 338935 9168 0 2 0xc82 syz-executor 18577 331422 9168 0 2 0xc82 syz-executor 35696 24566 0 0 3 0x14200 acct acct 4757 466720 1 0 3 0x100083 ttyin getty 13341 362551 9168 0 2 0xc82 syz-executor 16614 396794 9168 0 3 0x2 kmmaplk syz-executor 25552 162771 9168 0 2 0xc82 syz-executor 42506 143716 0 0 3 0x14200 bored sosplice 27577 173801 9168 0 2 0x2 syz-executor 57200 317712 9168 0 3 0x82 wait syz-executor 9168 124715 54214 0 3 0x82 kqread syz-executor 54214 113484 64637 0 3 0x10008a sigsusp ksh 64637 340957 26526 0 3 0x98 kqread sshd-session 26526 273638 28478 0 3 0x92 kqread sshd-session 28478 171627 1 0 3 0x88 kqread sshd 2804 95411 82248 74 3 0x1100092 bpf pflogd 82248 354066 1 0 3 0x80 sbwait pflogd 80876 357195 41741 73 3 0x1100090 kqread syslogd 41741 444195 1 0 3 0x100082 sbwait syslogd 19421 115756 1 0 3 0x100080 kqread resolvd 22207 271012 0 0 3 0x14200 bored smr 23034 159273 0 0 2 0x14200 zerothread 96402 91604 0 0 3 0x14200 aiodoned aiodoned 48278 63030 0 0 3 0x14200 syncer update 70015 368130 0 0 3 0x14200 cleaner cleaner 61738 441924 0 0 3 0x14200 kmmaplk reaper 53821 511490 0 0 3 0x14200 pgdaemon pagedaemon 44739 150051 0 0 3 0x14200 bored viomb 38902 254752 0 0 3 0x40014200 acpi0 acpi0 9579 457817 0 0 3 0x40014200 idle1 1836 281978 0 0 3 0x14200 bored softnet7 43282 214509 0 0 3 0x14200 bored softnet6 71375 244022 0 0 3 0x14200 bored softnet5 53092 375003 0 0 3 0x14200 bored softnet4 96512 47573 0 0 3 0x14200 bored softnet3 18557 459390 0 0 3 0x14200 bored softnet2 50857 215038 0 0 3 0x14200 bored softnet1 40122 360245 0 0 3 0x14200 bored softnet0 59448 216108 0 0 3 0x14200 bored systqmp 76895 517369 0 0 3 0x14200 bored systq 96799 367588 0 0 3 0x14200 tmoslp softclockmp 5588 272393 0 0 2 0x40014200 softclock 21653 317882 0 0 3 0x40014200 idle0 1 232662 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 (0xfffffd806b979710) #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:746 #7 Xsyscall+0x128 Process 69573 (arp) thread 0xffff80003c47aaa8 (507798) Process 29828 (syz-executor) thread 0xffff80003c4822c8 (102148) Process 27577 (syz-executor) thread 0xffff8000ffff34d0 (173801) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10263 11080K 12419K 166960K 15304 0 pcb 17 16K 22K 166960K 1259 0 rtable 201 15K 15K 166960K 1177 0 pf 50 20K 131092K 166960K 574 0 ifaddr 42 8K 8K 166960K 321 0 ifgroup 69 2K 3K 166960K 526 0 sysctl 4 1K 9K 166960K 143 0 counters 76 37K 38K 166960K 830 0 ioctlops 0 0K 6K 166960K 2799 0 iov 0 0K 32K 166960K 636 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1579 99K 100K 166960K 5858 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 5 17K 25K 166960K 88 0 VM map 2 1K 1K 166960K 2 0 sem 27 21K 21K 166960K 138 0 dirhash 12 2K 3K 166960K 111 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 110K 166960K 5288 0 sigio 0 0K 0K 166960K 244 0 proc 67 83K 164K 166960K 1625 0 subproc 72 4K 4K 166960K 234 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 867 0 in_multi 58 4K 6K 166960K 499 0 ether_multi 1 0K 0K 166960K 50 0 mrt 2 0K 0K 166960K 23 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 253 1129K 1129K 166960K 253 0 exec 0 0K 1K 166960K 1878 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 217 144K 192K 166960K 51091 0 UVM aobj 131 4K 5K 166960K 134 0 pinsyscall 37 74K 100K 166960K 6848 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 309 0 NDP 16 0K 1K 166960K 228 0 temp 90 8656K 8784K 166960K 246426 0 kqueue 7 12K 32K 166960K 1180 0 SYN cache 2 8K 16K 166960K 3 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 120 544 0 542 4 3 1 3 0 8 0 rtentry 176 412 0 348 5 2 3 5 0 8 0 unpcb 144 4139 0 4129 29 26 3 6 0 8 2 syncache 336 14 0 14 8 8 0 1 0 8 0 tcpqe 32 6 0 6 5 5 0 1 0 8 0 tcpcb 736 1698 0 1694 33 31 2 7 0 8 1 arp 136 48 0 40 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 328 6045 0 6040 61 57 4 10 0 8 3 nd6 144 67 0 54 1 0 1 1 0 8 0 pkpcb 40 37 0 37 12 11 1 1 0 8 1 kcovpl 48 25 0 17 1 0 1 1 0 8 0 mppekey 1024 1 0 1 1 1 0 1 0 8 0 ppxss 1192 325 0 324 4 3 1 1 0 8 0 pppxif 1504 17 0 17 11 11 0 1 0 8 0 pfstscr 40 11 0 10 5 4 1 1 0 8 0 pffrag 232 80 0 72 1 0 1 1 0 482 0 pffrnode 88 68 0 60 1 0 1 1 0 8 0 pffrent 40 145 0 136 1 0 1 1 0 8 0 pfosfp 40 1433 0 1432 6 5 1 5 0 8 0 pfosfpen 112 1433 0 1430 21 20 1 21 0 8 0 pfrktable 1344 4 0 4 3 3 0 1 0 8 0 pfanchor 1288 2 0 0 1 0 1 1 0 8 0 pftag 88 6 0 0 1 0 1 1 0 8 0 pfstitem 24 209 0 184 1 0 1 1 0 8 0 pfstkey 128 227 0 202 3 1 2 3 0 8 0 pfstate 384 216 0 193 9 5 4 9 0 8 0 pfrule 1344 85 0 78 2 1 1 2 0 8 0 rttmr 136 4 0 4 3 3 0 1 0 8 0 art_heap8 4096 5 0 1 5 0 5 5 0 8 1 art_heap4 256 1971 0 1698 41 21 20 28 0 8 0 art_table 40 1976 0 1699 5 1 4 5 0 8 0 art_node 32 403 0 347 1 0 1 1 0 8 0 sysvmsgpl 40 26 0 13 1 0 1 1 0 8 0 semupl 112 4 0 4 2 2 0 1 0 8 0 semapl 112 122 0 97 1 0 1 1 0 8 0 shmpl 112 131 0 3 4 0 4 4 0 8 0 dirhash 1024 84 0 67 3 0 3 3 0 8 0 dino2pl 256 11983 0 10431 100 2 98 98 0 8 0 ffsino 296 11983 0 10431 120 0 120 120 0 8 0 nchpl 144 19507 0 18900 65 41 24 64 0 8 0 rtmask 32 42 0 42 12 11 1 1 0 8 1 uvmvnodes 80 5926 0 0 121 0 121 121 0 8 0 vnodes 216 5926 0 0 330 0 330 330 0 8 0 namei 1024 70528 0 70527 3 2 1 2 0 8 0 percpumem 16 430 0 377 1 0 1 1 0 8 0 kstatmem 264 360 0 322 4 1 3 3 0 8 0 scsiplug 72 23 0 23 15 14 1 1 0 8 1 scxspl 216 126002 0 126002 21 19 2 8 1 8 2 plimitpl 152 1494 0 1477 1 0 1 1 0 8 0 sigapl 424 5587 0 5535 9 1 8 9 0 8 0 knotepl 120 721 0 0 17 0 17 17 0 8 0 kqueuepl 224 2252 0 2246 25 24 1 5 0 8 0 pipepl 344 792 0 765 18 15 3 9 0 8 0 fdescpl 528 5528 0 5500 3 0 3 3 0 8 0 filepl 160 40601 0 40401 67 55 12 19 0 8 2 lockfpl 104 2192 0 2190 3 2 1 2 0 8 0 lockfspl 48 794 0 792 1 0 1 1 0 8 0 sessionpl 144 53 0 45 1 0 1 1 0 8 0 pgrppl 48 183 0 167 1 0 1 1 0 8 0 ucredpl 104 8089 0 8078 1 0 1 1 0 8 0 zombiepl 144 8717 0 8714 2 1 1 1 0 8 0 processpl 1232 5587 0 5535 7 2 5 7 0 8 0 procpl 664 14607 0 14552 10 3 7 9 0 8 0 sosppl 168 35 0 35 9 9 0 1 0 8 0 sockpl 752 10927 0 10910 92 83 9 17 0 8 7 mcl64k 65536 18 0 0 3 0 3 3 0 8 0 mcl16k 16384 5 0 0 1 0 1 1 0 8 0 mcl12k 12288 1 0 0 1 0 1 1 0 8 0 mcl9k 9216 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 6 0 0 1 0 1 1 0 8 0 mcl4k 4096 124 0 0 15 1 14 15 0 8 0 mcl2k2 2112 2 0 0 1 0 1 1 0 8 0 mcl2k 2048 69 0 0 5 0 5 5 0 8 0 mtagpl 96 67 0 0 2 0 2 2 0 8 0 mbufpl 256 1334 0 0 72 1 71 71 0 8 0 bufpl 280 49296 0 43153 440 0 440 440 0 8 0 anonpl 32 16513 0 0 132 0 132 132 0 246 0 amapchunkpl 152 178195 0 177671 102 73 29 41 0 158 1 amappl16 200 18491 0 18417 163 142 21 40 0 8 8 amappl15 192 13 0 13 1 1 0 1 0 8 0 amappl14 184 181 0 171 1 0 1 1 0 8 0 amappl13 176 7 0 7 2 2 0 1 0 8 0 amappl12 168 6447 0 6419 3 1 2 2 0 8 0 amappl11 160 51 0 42 1 0 1 1 0 8 0 amappl10 152 4 0 4 1 1 0 1 0 8 0 amappl9 144 255 0 253 1 0 1 1 0 8 0 amappl8 136 23 0 20 1 0 1 1 0 8 0 amappl7 128 162 0 151 1 0 1 1 0 8 0 amappl6 120 355 0 350 1 0 1 1 0 8 0 amappl5 112 195 0 188 1 0 1 1 0 8 0 amappl4 104 375 0 353 1 0 1 1 0 8 0 amappl3 96 31499 0 31416 6 2 4 4 0 8 0 amappl2 88 5873 0 5809 6 3 3 3 0 8 0 amappl1 80 32591 0 32057 19 4 15 17 0 8 0 amappl 88 49110 0 48953 5 0 5 5 0 92 0 dma65536 65536 1 0 1 1 1 0 1 0 8 0 dma4096 4096 1 0 1 1 1 0 1 0 8 0 dma2048 2048 1 0 1 1 1 0 1 0 8 0 dma1024 1024 2 0 1 1 0 1 1 0 8 0 dma256 256 9 0 9 4 4 0 1 0 8 0 dma128 128 259 0 259 5 5 0 1 0 8 0 dma64 64 7 0 7 2 2 0 1 0 8 0 dma32 32 9 0 9 3 3 0 1 0 8 0 dma16 16 21 0 20 1 0 1 1 0 8 0 aobjpl 72 133 0 3 3 0 3 3 0 8 0 uaddrrnd 24 5528 0 5500 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 5528 0 5500 1 0 1 1 0 8 0 vmmpekpl 168 46417 0 46368 3 0 3 3 0 8 0 vmmpepl 168 352869 0 351140 173 65 108 117 0 357 8 vmsppl 488 5527 0 5500 6 1 5 5 0 8 0 rwobjpl 80 95285 0 88339 169 13 156 156 0 8 3 pdppl 4096 11064 0 11000 148 82 66 82 0 8 2 pvpl 32 23936 0 0 191 0 191 191 0 265 0 pmappl 256 5527 0 5500 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 450 0 156 9 0 9 9 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8379dff0) 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:662 comcnputc(800,66) at comcnputc+0x250 comcn_read_reg sys/dev/ic/com.c:1655 [inline] comcnputc(800,66) at comcnputc+0x250 sys/dev/ic/com.c:1269 cnputc(66) at cnputc+0x67 sys/dev/cons.c:218 kputchar(66,5,0) at kputchar+0x2ed sys/kern/subr_prf.c:367 kprintf() at kprintf+0x29a5 sys/kern/subr_prf.c:-1 printf(ffffffff834193cf) at printf+0x8b sys/kern/subr_prf.c:529 trap_print(ffff800030bff320,6) at trap_print+0x70 sys/arch/amd64/amd64/trap.c:624 kerntrap(ffff800030bff320) at kerntrap+0x2e6 sys/arch/amd64/amd64/trap.c:485 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff80000147f000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:586 dtclose(11e5f,81,2000,ffff80003c482fc0) at dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(11e5f,81,2000,ffff80003c482fc0) at dtclose+0x109 sys/dev/dt/dt_dev.c:232 end trace frame: 0xffff800030bff4c0, count: 0 ddb{0}> trace x86_ipi_db(ffffffff8379dff0) 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:662 comcnputc(800,66) at comcnputc+0x250 comcn_read_reg sys/dev/ic/com.c:1655 [inline] comcnputc(800,66) at comcnputc+0x250 sys/dev/ic/com.c:1269 cnputc(66) at cnputc+0x67 sys/dev/cons.c:218 kputchar(66,5,0) at kputchar+0x2ed sys/kern/subr_prf.c:367 kprintf() at kprintf+0x29a5 sys/kern/subr_prf.c:-1 printf(ffffffff834193cf) at printf+0x8b sys/kern/subr_prf.c:529 trap_print(ffff800030bff320,6) at trap_print+0x70 sys/arch/amd64/amd64/trap.c:624 kerntrap(ffff800030bff320) at kerntrap+0x2e6 sys/arch/amd64/amd64/trap.c:485 alltraps_kern_meltdown() at alltraps_kern_meltdown+0x7b dt_ioctl_record_stop(ffff80000147f000) at dt_ioctl_record_stop+0x108 sys/dev/dt/dt_dev.c:586 dtclose(11e5f,81,2000,ffff80003c482fc0) at dtclose+0x109 dt_pcb_purge sys/dev/dt/dt_dev.c:-1 [inline] dtclose(11e5f,81,2000,ffff80003c482fc0) at dtclose+0x109 sys/dev/dt/dt_dev.c:232 spec_close(ffff800030bff4d0) at spec_close+0x466 sys/kern/spec_vnops.c:-1 VOP_CLOSE(fffffd805fbc4ea0,81,fffffd80097fb340,ffff80003c482fc0) at VOP_CLOSE+0x132 sys/kern/vfs_vops.c:156 vn_closefile(fffffd806b918ad8,ffff80003c482fc0) at vn_closefile+0x12b vn_close sys/kern/vfs_vnops.c:292 [inline] vn_closefile(fffffd806b918ad8,ffff80003c482fc0) at vn_closefile+0x12b sys/kern/vfs_vnops.c:615 fdrop(fffffd806b918ad8,ffff80003c482fc0) at fdrop+0x121 sys/kern/kern_descrip.c:1280 closef(fffffd806b918ad8,ffff80003c482fc0) at closef+0x192 sys/kern/kern_descrip.c:1264 fdfree(ffff80003c482fc0) at fdfree+0x116 sys/kern/kern_descrip.c:1195 exit1(ffff80003c482fc0,0,0,1) at exit1+0x576 sys/kern/kern_exit.c:215 sys_exit(ffff80003c482fc0,ffff800030bff840,ffff800030bff790) at sys_exit+0x1a sys/kern/kern_exit.c:-1 syscall(ffff800030bff840) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800030bff840) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:746 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x743155723d10, count: -24 ddb{0}> machine ddbcpu 1 Stopped at savectx+0xae: movl $0,%gs:0x688 savectx() at savectx+0xae end of kernel end trace frame: 0x6f8471442ac0, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0x6f8471442ac0, count: -1