panic: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_page.c", line 144 Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *329684 49274 0 0x8000000 0x4000000 1 syz-executor 453866 44514 0 0x14000 0x40000200 0 softclock db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff830dcf7e) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83092018,ffffffff83032dfc,90,ffffffff830932c4) at __assert+0x29 uvm_pagealloc_pg(fffffd800764c980,fffffd806e0659e8,260b8c000,0) at uvm_pagealloc_pg+0x521 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd806e0659e8,260b8c000,0,3) at uvm_pagealloc+0x23e sys/uvm/uvm_page.c:912 pmap_get_ptp(fffffd806e0659b8,4c171827000) at pmap_get_ptp+0x1c6 pmap_enter(fffffd806e0659b8,4c171827000,60870000,3,20) at pmap_enter+0x389 uvm_fault_upper_lookup(ffff80002a0dc950,ffff80002a0dc988,ffff80002a0dc850,ffff80002a0dc8d0) at uvm_fault_upper_lookup+0x389 uvm_fault(fffffd8069855008,4c171826000,0,2) at uvm_fault+0x169 sys/uvm/uvm_fault.c:605 upageflttrap(ffff80002a0dcad0,4c171826848) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff80002a0dcad0) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x4c1074c7340, count: 3 https://www.openbsd.org/ddb.html describes the minimum info required in bug reports. Insufficient info makes it difficult to find and fix bugs. ddb{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: kernel diagnostic assertion "dupe == NULL" failed: file "/syzkaller/managers/multicore/kernel/sys/uvm/uvm_page.c", line 144 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff830dcf7e) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83092018,ffffffff83032dfc,90,ffffffff830932c4) at __assert+0x29 uvm_pagealloc_pg(fffffd800764c980,fffffd806e0659e8,260b8c000,0) at uvm_pagealloc_pg+0x521 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd806e0659e8,260b8c000,0,3) at uvm_pagealloc+0x23e sys/uvm/uvm_page.c:912 pmap_get_ptp(fffffd806e0659b8,4c171827000) at pmap_get_ptp+0x1c6 pmap_enter(fffffd806e0659b8,4c171827000,60870000,3,20) at pmap_enter+0x389 uvm_fault_upper_lookup(ffff80002a0dc950,ffff80002a0dc988,ffff80002a0dc850,ffff80002a0dc8d0) at uvm_fault_upper_lookup+0x389 uvm_fault(fffffd8069855008,4c171826000,0,2) at uvm_fault+0x169 sys/uvm/uvm_fault.c:605 upageflttrap(ffff80002a0dcad0,4c171826848) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff80002a0dcad0) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x4c1074c7340, count: -12 ddb{1}> show registers rdi 0 rsi 0x1 rbp 0xffff80002a0dc470 rbx 0xffff800029b7cd87 rdx 0xffff8000011a6c40 rcx 0xffff80002a057458 rax 0xffff800029b7bff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0xd6037fb81f398bdd r11 0x2e512b1df83a7858 r12 0xffff800029b7cb88 r13 0 r14 0 r15 0x1 rip 0xffffffff826016b5 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff80002a0dc460 ss 0 db_enter+0x25: addq $0x8,%rsp ddb{1}> show proc PROC (syz-executor) tid=329684 pid=49274 tcnt=3 stat=onproc flags process=8000000 proc=4000000 runpri=50, usrpri=50, slppri=24, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff800029fd8f38,0xffff800037234550 process=0xffff800029fe8918 user=0xffff80002a0d7000, vmspace=0xfffffd8069855008 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 32568 197251 76872 60928 2 0x8000010 syz-executor 32568 415596 76872 60928 3 0xc000090 fsleep syz-executor 74907 178430 33646 0 2 0x8000010 syz-executor 74907 204176 33646 0 3 0xc000090 fsleep syz-executor 74907 104275 33646 0 2 0xc000010 syz-executor 17432 206746 63333 0 2 0x8000000 syz-executor 17432 163073 63333 0 3 0xc000080 fsleep syz-executor 17432 152131 63333 0 3 0xc000080 fsleep syz-executor 49274 306134 74558 0 2 0x8000000 syz-executor *49274 329684 74558 0 7 0xc000000 syz-executor 49274 507813 74558 0 2 0xc000000 syz-executor 34648 412397 50241 0 3 0x8000090 nanoslp syz-executor 34648 281167 50241 0 3 0xc000090 sbwait syz-executor 34648 180136 50241 0 3 0xc000090 fsleep syz-executor 50241 291102 75737 0 3 0x8000082 nanoslp syz-executor 2767 451840 75737 0 3 0x8000082 piperd syz-executor 74558 413615 75737 0 3 0x8000082 nanoslp syz-executor 76872 389106 75737 0 2 0x8000482 syz-executor 63333 307849 75737 0 3 0x8000082 nanoslp syz-executor 48547 402903 75737 0 3 0x8000082 piperd syz-executor 55117 323313 75737 0 3 0x8000082 piperd syz-executor 33646 438132 75737 0 3 0x8000082 nanoslp syz-executor 80666 177545 1 0 3 0x18100083 ttyin getty 48806 81578 0 0 3 0x14200 bored sosplice 75737 230806 31250 0 2 0x8000002 syz-executor 31250 304350 81309 0 3 0x810008a sigsusp ksh 81309 393544 15130 0 3 0x18000098 kqread sshd-session 15130 491230 64503 0 3 0x18000092 kqread sshd-session 64503 500138 1 0 3 0x18000088 kqread sshd 80037 97793 29 74 3 0x19100092 bpf pflogd 29 415223 1 0 3 0x18000080 sbwait pflogd 66289 263843 39522 73 3 0x19100090 kqread syslogd 39522 159183 1 0 3 0x18100082 sbwait syslogd 7186 156684 1 0 3 0x18100080 kqread resolvd 56497 269540 63265 77 3 0x18100092 kqread dhcpleased 63881 200099 63265 77 3 0x18100092 kqread dhcpleased 63265 92738 1 0 3 0x18000080 kqread dhcpleased 9236 134153 0 0 3 0x14200 bored smr 478 416245 0 0 2 0x14200 zerothread 38303 213617 0 0 3 0x14200 aiodoned aiodoned 3960 487481 0 0 3 0x14200 syncer update 24710 21269 0 0 3 0x14200 cleaner cleaner 10645 334532 0 0 3 0x14200 reaper reaper 33032 321187 0 0 3 0x14200 pgdaemon pagedaemon 87954 437542 0 0 3 0x14200 bored viomb 74391 420842 0 0 3 0x40014200 acpi0 acpi0 16800 68731 0 0 3 0x40014200 idle1 51361 17872 0 0 3 0x14200 bored softnet3 98732 292784 0 0 3 0x14200 bored softnet2 40791 11870 0 0 3 0x14200 bored softnet1 6576 201002 0 0 3 0x14200 bored softnet0 91399 326213 0 0 3 0x14200 bored systqmp 27815 389720 0 0 3 0x14200 bored systq 75566 73595 0 0 3 0x14200 tmoslp softclockmp 44514 453866 0 0 7 0x40014200 softclock 35395 317052 0 0 3 0x40014200 idle0 1 156917 0 0 3 0x8000082 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &pmap->pm_mtx r = 0 (0xfffffd806e0659c8) #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 pmap_enter+0x246 rcr3 machine/cpufunc.h:139 [inline] #3 pmap_enter+0x246 pmap_map_ptes sys/arch/amd64/amd64/pmap.c:430 [inline] #3 pmap_enter+0x246 sys/arch/amd64/amd64/pmap.c:2756 #4 uvm_fault_upper_lookup+0x389 #5 uvm_fault+0x169 sys/uvm/uvm_fault.c:605 #6 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 #7 usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 #8 recall_trap+0x8 Process 49274 (syz-executor) thread 0xffff80002a057458 (329684) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10238 10175K 10696K 166960K 14722 0 pcb 18 18K 20K 166960K 716 0 rtable 241 10K 10K 166960K 4220 0 pf 44 19K 24K 166960K 509 0 ifaddr 47 10K 10K 166960K 553 0 ifgroup 63 2K 3K 166960K 633 0 sysctl 4 1K 1K 166960K 4 0 counters 68 36K 37K 166960K 366 0 ioctlops 0 0K 8K 166960K 1987 0 iov 0 0K 37K 166960K 148 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1498 94K 95K 166960K 5304 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 9K 166960K 36 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 187 0 dirhash 15 2K 3K 166960K 45 0 ACPI 1697 195K 286K 166960K 12548 0 file desc 15 53K 85K 166960K 3392 0 sigio 0 0K 0K 166960K 38 0 proc 70 91K 128K 166960K 3843 0 subproc 104 6K 7K 166960K 1600 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 269 0 in_multi 103 7K 7K 166960K 1398 0 ether_multi 1 0K 0K 166960K 9 0 mrt 1 0K 0K 166960K 5 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 307 1367K 1367K 166960K 307 0 exec 0 0K 1K 166960K 2403 0 pfkey data 0 0K 0K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 248 148K 156K 166960K 27431 0 UVM aobj 62 7K 7K 166960K 65 0 pinsyscall 40 80K 100K 166960K 7469 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 103 0 NDP 14 0K 1K 166960K 407 0 temp 81 6820K 6932K 166960K 121467 0 kqueue 13 20K 33K 166960K 317 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 24 0 0 1 0 1 1 0 8 0 rtpcb 120 650 0 647 6 5 1 3 0 8 0 rtentry 112 1409 0 1305 5 2 3 4 0 8 0 unpcb 144 2637 0 2610 30 24 6 6 0 8 5 syncache 336 7 0 7 4 4 0 1 0 8 0 tcpqe 32 2 0 2 2 2 0 1 0 8 0 tcpcb 808 1149 0 1143 44 29 15 15 0 8 14 arp 120 254 0 235 1 0 1 1 0 8 0 inpcb 336 4100 0 4087 69 57 12 13 0 8 10 nd6 136 385 0 358 1 0 1 1 0 8 0 pkpcb 40 10 0 10 7 6 1 1 0 8 1 kcovpl 48 123 0 115 1 0 1 1 0 8 0 ppxss 1168 22 0 22 8 7 1 1 0 8 1 pfstscr 40 8 0 8 7 7 0 1 0 8 0 pffrag 232 17 0 13 3 2 1 1 0 482 0 pffrnode 88 17 0 13 3 2 1 1 0 8 0 pffrent 40 121 0 117 3 2 1 1 0 8 0 pfosfp 40 1431 0 1006 5 0 5 5 0 8 0 pfosfpen 112 1431 0 715 21 0 21 21 0 8 0 pfrktable 1344 36 0 32 3 2 1 1 0 8 0 pfanchor 1288 12 0 3 1 0 1 1 0 8 0 pftag 88 7 0 7 3 2 1 1 0 8 1 pfstitem 24 256 0 211 1 0 1 1 0 8 0 pfstkey 128 280 0 229 2 0 2 2 0 8 0 pfstate 376 262 0 220 7 1 6 6 0 8 0 pfrule 1344 58 0 45 4 2 2 2 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 5592 0 5140 42 13 29 29 0 8 0 art_table 32 5594 0 5140 5 1 4 4 0 8 0 art_node 16 1406 0 1313 1 0 1 1 0 8 0 sysvmsgpl 40 1 0 1 1 1 0 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 185 0 175 1 0 1 1 0 8 0 shmpl 112 62 0 3 2 0 2 2 0 8 0 dirhash 1024 39 0 20 3 0 3 3 0 8 0 dino2pl 256 5252 0 3513 110 0 110 110 0 8 0 ffsino 272 5252 0 3513 117 0 117 117 0 8 0 nchpl 144 7916 0 6071 69 0 69 69 0 8 0 uvmvnodes 80 7361 0 0 151 0 151 151 0 8 0 vnodes 216 7361 0 0 409 0 409 409 0 8 0 namei 1024 43550 0 43550 9 8 1 2 0 8 1 percpumem 16 197 0 149 1 0 1 1 0 8 0 vcpupl 3904 10 0 2 2 0 2 2 0 8 0 vmpool 696 13 0 5 1 0 1 1 0 8 0 pfiaddrpl 120 10 0 7 3 2 1 1 0 8 0 kstatmem 264 326 0 298 5 2 3 3 0 8 0 scsiplug 72 6 0 6 5 4 1 1 0 8 1 scxspl 216 71702 0 71702 12 10 2 8 1 8 2 plimitpl 152 841 0 822 1 0 1 1 0 8 0 sigapl 424 3497 0 3449 10 3 7 9 0 8 0 futexpl 64 30349 0 30344 9 8 1 1 0 8 0 knotepl 120 993 0 0 25 0 25 25 0 8 0 kqueuepl 216 878 0 869 19 18 1 5 0 8 0 pipepl 320 785 0 758 12 9 3 8 0 8 0 fdescpl 496 3455 0 3426 8 3 5 5 0 8 0 filepl 152 26070 0 25771 88 70 18 22 0 8 5 lockfpl 104 1103 0 1100 3 1 2 2 0 8 1 lockfspl 48 383 0 380 1 0 1 1 0 8 0 sessionpl 144 137 0 128 1 0 1 1 0 8 0 pgrppl 48 282 0 265 1 0 1 1 0 8 0 ucredpl 104 4239 0 4222 1 0 1 1 0 8 0 zombiepl 144 3449 0 3449 2 1 1 1 0 8 1 processpl 1160 3497 0 3449 8 3 5 6 0 8 0 procpl 648 6626 0 6569 11 4 7 8 0 8 1 srpgc 96 15 0 15 6 6 0 1 0 8 0 sosppl 168 5 0 5 3 3 0 1 0 8 0 sockpl 664 7447 0 7404 111 91 20 26 0 8 16 mcl64k 65536 5 0 0 1 0 1 1 0 8 0 mcl16k 16384 3 0 0 1 0 1 1 0 8 0 mcl12k 12288 4 0 0 1 0 1 1 0 8 0 mcl8k 8192 5 0 0 1 0 1 1 0 8 0 mcl4k 4096 7 0 0 1 0 1 1 0 8 0 mcl2k2 2112 1 0 0 1 0 1 1 0 8 0 mcl2k 2048 338 0 0 29 1 28 29 0 8 1 mtagpl 96 8 0 0 1 0 1 1 0 8 0 mbufpl 256 4640 0 0 285 0 285 285 0 8 0 bufpl 280 13998 0 6681 526 0 526 526 0 8 0 anonpl 24 510206 0 500867 168 95 73 86 0 185 15 amapchunkpl 152 87227 0 86425 80 45 35 46 0 158 1 amappl16 200 8926 0 8898 91 79 12 35 0 8 8 amappl15 192 11 0 11 2 2 0 1 0 8 0 amappl14 184 358 0 346 1 0 1 1 0 8 0 amappl13 176 18 0 18 1 1 0 1 0 8 0 amappl12 168 5923 0 5893 4 2 2 3 0 8 0 amappl11 160 56 0 42 1 0 1 1 0 8 0 amappl10 152 19 0 18 1 0 1 1 0 8 0 amappl9 144 125 0 125 1 1 0 1 0 8 0 amappl8 136 26 0 23 1 0 1 1 0 8 0 amappl7 128 339 0 327 1 0 1 1 0 8 0 amappl6 120 1311 0 1309 1 0 1 1 0 8 0 amappl5 112 590 0 578 1 0 1 1 0 8 0 amappl4 104 667 0 649 1 0 1 1 0 8 0 amappl3 96 16676 0 16566 4 0 4 4 0 8 0 amappl2 88 2242 0 2177 2 0 2 2 0 8 0 amappl1 80 24698 0 24117 15 1 14 14 0 8 0 amappl 88 26093 0 25915 8 3 5 6 0 92 0 dma8192 8192 1 0 1 1 1 0 1 0 8 0 dma4096 4096 2 0 2 2 2 0 1 0 8 0 dma1024 1024 1 0 0 1 0 1 1 0 8 0 dma256 256 8 0 8 3 3 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 64 0 3 2 0 2 2 0 8 0 uaddrrnd 24 3468 0 3431 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 3468 0 3431 1 0 1 1 0 8 0 vmmpekpl 168 31535 0 31486 4 0 4 4 0 8 0 vmmpepl 168 217399 0 215589 155 57 98 112 0 357 12 vmsppl 440 3467 0 3431 8 3 5 5 0 8 0 rwobjpl 56 69310 0 60929 130 7 123 123 0 8 1 pdppl 4096 6943 0 6870 257 179 78 88 0 8 5 pvpl 32 46320 0 0 374 2 372 372 0 265 0 pmappl 248 3467 0 3431 3 0 3 3 0 8 0 extentpl 40 56 0 38 1 0 1 1 0 8 0 phpool 112 990 0 304 20 0 20 20 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff834c5ff0) 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 __mp_lock(ffffffff835efe18) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff835efe18) at __mp_lock+0x199 sys/kern/kern_lock.c:144 __mp_acquire_count(ffffffff835efe18,1) at __mp_acquire_count+0x58 mi_switch() at mi_switch+0x658 sys/kern/sched_bsd.c:460 sleep_finish(0,1) at sleep_finish+0x219 sys/kern/kern_synch.c:416 msleep(ffffffff834f97b0,ffffffff83415cb0,0,ffffffff830dac54,0) at msleep+0x13b sys/kern/kern_synch.c:249 softclock_thread(ffff8000fffff440) at softclock_thread+0x11f sys/kern/kern_timeout.c:807 end trace frame: 0x0, count: 6 ddb{0}> trace x86_ipi_db(ffffffff834c5ff0) 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 __mp_lock(ffffffff835efe18) at __mp_lock+0x199 __mp_lock_spin sys/kern/kern_lock.c:113 [inline] __mp_lock(ffffffff835efe18) at __mp_lock+0x199 sys/kern/kern_lock.c:144 __mp_acquire_count(ffffffff835efe18,1) at __mp_acquire_count+0x58 mi_switch() at mi_switch+0x658 sys/kern/sched_bsd.c:460 sleep_finish(0,1) at sleep_finish+0x219 sys/kern/kern_synch.c:416 msleep(ffffffff834f97b0,ffffffff83415cb0,0,ffffffff830dac54,0) at msleep+0x13b sys/kern/kern_synch.c:249 softclock_thread(ffff8000fffff440) at softclock_thread+0x11f sys/kern/kern_timeout.c:807 end trace frame: 0x0, count: -9 ddb{0}> machine ddbcpu 1 Stopped at db_enter+0x25: addq $0x8,%rsp db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff830dcf7e) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83092018,ffffffff83032dfc,90,ffffffff830932c4) at __assert+0x29 uvm_pagealloc_pg(fffffd800764c980,fffffd806e0659e8,260b8c000,0) at uvm_pagealloc_pg+0x521 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd806e0659e8,260b8c000,0,3) at uvm_pagealloc+0x23e sys/uvm/uvm_page.c:912 pmap_get_ptp(fffffd806e0659b8,4c171827000) at pmap_get_ptp+0x1c6 pmap_enter(fffffd806e0659b8,4c171827000,60870000,3,20) at pmap_enter+0x389 uvm_fault_upper_lookup(ffff80002a0dc950,ffff80002a0dc988,ffff80002a0dc850,ffff80002a0dc8d0) at uvm_fault_upper_lookup+0x389 uvm_fault(fffffd8069855008,4c171826000,0,2) at uvm_fault+0x169 sys/uvm/uvm_fault.c:605 upageflttrap(ffff80002a0dcad0,4c171826848) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff80002a0dcad0) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x4c1074c7340, count: 3 ddb{1}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:437 panic(ffffffff830dcf7e) at panic+0x1e5 sys/kern/subr_prf.c:198 __assert(ffffffff83092018,ffffffff83032dfc,90,ffffffff830932c4) at __assert+0x29 uvm_pagealloc_pg(fffffd800764c980,fffffd806e0659e8,260b8c000,0) at uvm_pagealloc_pg+0x521 sys/uvm/uvm_page.c:695 uvm_pagealloc(fffffd806e0659e8,260b8c000,0,3) at uvm_pagealloc+0x23e sys/uvm/uvm_page.c:912 pmap_get_ptp(fffffd806e0659b8,4c171827000) at pmap_get_ptp+0x1c6 pmap_enter(fffffd806e0659b8,4c171827000,60870000,3,20) at pmap_enter+0x389 uvm_fault_upper_lookup(ffff80002a0dc950,ffff80002a0dc988,ffff80002a0dc850,ffff80002a0dc8d0) at uvm_fault_upper_lookup+0x389 uvm_fault(fffffd8069855008,4c171826000,0,2) at uvm_fault+0x169 sys/uvm/uvm_fault.c:605 upageflttrap(ffff80002a0dcad0,4c171826848) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff80002a0dcad0) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x4c1074c7340, count: -12