panic: mtx 0xffffffff8396b418: locking against myself Stopped at db_enter+0x25: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND *440150 26175 0 0 0 0 syz-executor 510810 31729 60928 0x10 0 1 syz-executor db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833e3610) at panic+0x1e5 sys/kern/subr_prf.c:198 mtx_enter_try(ffffffff8396b418) at mtx_enter_try+0x1bf sys/kern/kern_lock.c:271 mtx_enter(ffffffff8396b418) at mtx_enter+0x60 sys/kern/kern_lock.c:239 uvm_pageclean(fffffd8008290aa0) at uvm_pageclean+0x290 uvm_pagedequeue sys/uvm/uvm_page.c:-1 [inline] uvm_pageclean(fffffd8008290aa0) at uvm_pageclean+0x290 sys/uvm/uvm_page.c:980 uvm_pagefree(fffffd8008290aa0) at uvm_pagefree+0x26 sys/uvm/uvm_page.c:1020 uvn_get(fffffd805f4daa88,0,ffff8000307e82e8,ffff8000307e82c4,0,2,e3d35ed173bef778,ffff8000307e8540) at uvn_get+0x68b sys/uvm/uvm_vnode.c:1118 uvm_fault_lower_io(ffff8000307e8508,ffff8000307e8540,ffff8000307e8370,ffff8000307e8378) at uvm_fault_lower_io+0x319 sys/uvm/uvm_fault.c:1588 uvm_fault_lower(ffff8000307e8508,ffff8000307e8540,ffff8000307e8480) at uvm_fault_lower+0x278 sys/uvm/uvm_fault.c:1362 uvm_fault(fffffd806bea3978,200000000000,0,2) at uvm_fault+0x272 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff8000307e8690,200000000140) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff8000307e8690) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x71383e1a8680, count: 2 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{0}> ddb{0}> set $lines = 0 ddb{0}> set $maxwidth = 0 ddb{0}> show panic *cpu0: mtx 0xffffffff8396b418: locking against myself ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833e3610) at panic+0x1e5 sys/kern/subr_prf.c:198 mtx_enter_try(ffffffff8396b418) at mtx_enter_try+0x1bf sys/kern/kern_lock.c:271 mtx_enter(ffffffff8396b418) at mtx_enter+0x60 sys/kern/kern_lock.c:239 uvm_pageclean(fffffd8008290aa0) at uvm_pageclean+0x290 uvm_pagedequeue sys/uvm/uvm_page.c:-1 [inline] uvm_pageclean(fffffd8008290aa0) at uvm_pageclean+0x290 sys/uvm/uvm_page.c:980 uvm_pagefree(fffffd8008290aa0) at uvm_pagefree+0x26 sys/uvm/uvm_page.c:1020 uvn_get(fffffd805f4daa88,0,ffff8000307e82e8,ffff8000307e82c4,0,2,e3d35ed173bef778,ffff8000307e8540) at uvn_get+0x68b sys/uvm/uvm_vnode.c:1118 uvm_fault_lower_io(ffff8000307e8508,ffff8000307e8540,ffff8000307e8370,ffff8000307e8378) at uvm_fault_lower_io+0x319 sys/uvm/uvm_fault.c:1588 uvm_fault_lower(ffff8000307e8508,ffff8000307e8540,ffff8000307e8480) at uvm_fault_lower+0x278 sys/uvm/uvm_fault.c:1362 uvm_fault(fffffd806bea3978,200000000000,0,2) at uvm_fault+0x272 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff8000307e8690,200000000140) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff8000307e8690) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x71383e1a8680, count: -13 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff8000307e8030 rbx 0xffffffff83839dcf cpu_info_full_primary+0x2dcf rdx 0 rcx 0xffff8000ffff19c0 rax 0xffffffff83838ff0 cpu_info_full_primary+0x1ff0 r8 0x101010101010101 r9 0x8080808080808080 r10 0x118d43c7eaf5ee4a r11 0x9240026b94c4fe77 r12 0xffffffff83839bd0 cpu_info_full_primary+0x2bd0 r13 0 r14 0 r15 0x1 rip 0xffffffff8182c725 db_enter+0x25 cs 0x8 rflags 0x246 rsp 0xffff8000307e8020 ss 0 db_enter+0x25: addq $0x8,%rsp ddb{0}> show proc PROC (syz-executor) tid=440150 pid=26175 tcnt=3 stat=onproc flags process=0 proc=0 runpri=50, usrpri=50, slppri=16, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000ffff0020,0xffff8000fffea7e8 process=0xffff8000fffe7358 user=0xffff8000307e3000, vmspace=0xfffffd806bea3978 estcpu=36, cpticks=2, pctcpu=0.0, user=1, sys=1, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND *26175 440150 21286 0 7 0 syz-executor 26175 464721 21286 0 3 0x4000000 biowait syz-executor 26175 486297 21286 0 3 0x4000080 fsleep syz-executor 31729 510810 81601 60928 7 0x10 syz-executor 31729 313316 81601 60928 2 0x4000090 syz-executor 91384 302875 70135 0 2 0 syz-executor 91384 186186 70135 0 3 0x4000080 msgwait syz-executor 91384 421021 70135 0 3 0x4000080 fsleep syz-executor 72233 59717 45014 0 3 0x80 nanoslp syz-executor 72233 369548 45014 0 3 0x4000080 kqread syz-executor 72233 222229 45014 0 3 0x4000080 kqread syz-executor 72233 318527 45014 0 3 0x4000080 fsleep syz-executor 67602 14333 12571 0 3 0x80 nanoslp syz-executor 67602 362494 12571 0 3 0x4000080 sbwait syz-executor 67602 51104 12571 0 3 0x4000080 fsleep syz-executor 65680 510025 93292 -1 3 0x90 nanoslp syz-executor 65680 519902 93292 -1 3 0x4000090 ttyout syz-executor 65680 359188 93292 -1 3 0x4000090 fsleep syz-executor 65680 306702 93292 -1 3 0x4000090 fsleep syz-executor 34590 448557 0 0 3 0x14200 acct acct 99957 36801 0 0 3 0x14200 bored sosplice 81601 80836 15449 0 3 0x82 nanoslp syz-executor 12571 347779 15449 0 3 0x82 nanoslp syz-executor 50288 119582 15449 0 3 0x82 piperd syz-executor 31390 313617 15449 0 3 0x82 nanoslp syz-executor 45014 365382 15449 0 3 0x82 nanoslp syz-executor 21286 493702 15449 0 3 0x82 nanoslp syz-executor 93292 101468 15449 0 3 0x82 nanoslp syz-executor 70135 243330 15449 0 3 0x82 nanoslp syz-executor 15449 450705 27990 0 2 0x2 syz-executor 27990 26954 54838 0 3 0x10008a sigsusp ksh 54838 472368 97108 0 3 0x98 kqread sshd-session 97108 146008 30914 0 3 0x92 kqread sshd-session 24082 195883 1 0 3 0x100083 ttyin getty 30914 502913 1 0 3 0x88 kqread sshd 22036 447248 43574 74 3 0x1100092 bpf pflogd 43574 494512 1 0 3 0x80 sbwait pflogd 98132 214324 16362 73 3 0x1100090 kqread syslogd 16362 380466 1 0 3 0x100082 sbwait syslogd 60113 108117 1 0 3 0x100080 kqread resolvd 47396 191965 4820 77 3 0x100092 kqread dhcpleased 7074 389457 4820 77 3 0x100092 kqread dhcpleased 4820 453153 1 0 3 0x80 kqread dhcpleased 46830 248109 0 0 3 0x14200 bored smr 47128 511062 0 0 2 0x14200 zerothread 16915 424238 0 0 3 0x14200 aiodoned aiodoned 593 507516 0 0 3 0x14200 syncer update 71934 54906 0 0 3 0x14200 cleaner cleaner 6308 384826 0 0 3 0x14200 reaper reaper 8664 27671 0 0 3 0x14200 pgdaemon pagedaemon 61954 192906 0 0 3 0x14200 bored viomb 82158 150394 0 0 3 0x40014200 acpi0 acpi0 99384 491495 0 0 3 0x40014200 idle1 82353 98800 0 0 3 0x14200 bored softnet3 43696 286222 0 0 3 0x14200 bored softnet2 14633 299669 0 0 3 0x14200 bored softnet1 62038 53584 0 0 3 0x14200 bored softnet0 65822 334615 0 0 3 0x14200 bored systqmp 58138 198699 0 0 3 0x14200 bored systq 15668 147602 0 0 3 0x14200 tmoslp softclockmp 94623 485045 0 0 3 0x40014200 tmoslp softclock 11344 268473 0 0 3 0x40014200 idle0 1 28648 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks CPU 0: exclusive mutex &uvm.pageqlock r = 0 (0xffffffff8396b428) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1160 #1 mtx_enter_try+0x178 sys/kern/kern_lock.c:-1 #2 mtx_enter+0x60 sys/kern/kern_lock.c:239 #3 uvn_get+0x679 sys/uvm/uvm_vnode.c:1117 #4 uvm_fault_lower_io+0x319 sys/uvm/uvm_fault.c:1588 #5 uvm_fault_lower+0x278 sys/uvm/uvm_fault.c:1362 #6 uvm_fault+0x272 sys/uvm/uvm_fault.c:-1 #7 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 #8 usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 #9 recall_trap+0x8 Process 26175 (syz-executor) thread 0xffff8000ffff19c0 (440150) Process 26175 (syz-executor) thread 0xffff8000fffea7d8 (464721) Process 26175 (syz-executor) thread 0xffff8000fffebc58 (486297) ddb{0}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10209 11106K 11822K 166960K 11978 0 pcb 17 16K 18K 166960K 203 0 rtable 230 9K 10K 166960K 413 0 pf 34 17K 81K 166960K 81 0 ifaddr 40 6K 8K 166960K 63 0 ifgroup 55 2K 2K 166960K 102 0 sysctl 3 1K 1K 166960K 3 0 counters 64 36K 37K 166960K 114 0 ioctlops 0 0K 4K 166960K 1602 0 iov 1 2K 20K 166960K 20 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1377 87K 87K 166960K 1712 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 9 0 VM map 2 1K 1K 166960K 2 0 sem 11 0K 0K 166960K 17 0 dirhash 12 2K 2K 166960K 18 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 93K 166960K 502 0 sigio 0 0K 0K 166960K 20 0 proc 73 103K 127K 166960K 568 0 subproc 72 4K 4K 166960K 72 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 50 0 in_multi 88 6K 7K 166960K 114 0 ether_multi 1 0K 0K 166960K 5 0 mrt 0 0K 0K 166960K 3 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 79 360K 360K 166960K 79 0 exec 0 0K 1K 166960K 430 0 fusefs mount 1 32K 32K 166960K 1 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 250 168K 181K 166960K 6117 0 UVM aobj 15 2K 2K 166960K 15 0 pinsyscall 42 84K 108K 166960K 1580 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 13 0 NDP 12 0K 1K 166960K 42 0 temp 49 8680K 8745K 166960K 27142 0 kqueue 15 24K 32K 166960K 90 0 SYN cache 2 16K 16K 166960K 2 0 ddb{0}> 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 56 0 53 1 0 1 1 0 8 0 rtentry 176 131 0 29 6 0 6 6 0 8 0 unpcb 144 346 0 292 4 1 3 3 0 8 0 syncache 336 3 0 3 1 1 0 1 0 8 0 tcpcb 808 154 0 147 7 1 6 7 0 8 5 arp 128 23 0 8 1 0 1 1 0 8 0 inpcb 384 583 0 570 8 0 8 8 0 8 6 nd6 144 28 0 4 1 0 1 1 0 8 0 pkpcb 40 4 0 4 1 0 1 1 0 8 1 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1192 18 0 18 1 0 1 1 0 8 1 pppxif 1504 1 0 1 1 1 0 1 0 8 0 pffrag 232 6 0 2 1 0 1 1 0 482 0 pffrnode 88 5 0 1 1 0 1 1 0 8 0 pffrent 40 8 0 4 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 pfstitem 24 49 0 1 1 0 1 1 0 8 0 pfstkey 128 49 0 1 2 0 2 2 0 8 0 pfstate 384 49 0 1 5 0 5 5 0 8 0 pfrule 1344 28 0 19 2 1 1 2 0 8 0 rttmr 136 1 0 1 1 0 1 1 0 8 1 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 488 0 68 30 1 29 30 0 8 1 art_table 32 489 0 68 4 0 4 4 0 8 0 art_node 16 130 0 40 1 0 1 1 0 8 0 sysvmsgpl 40 5 0 4 1 0 1 1 0 8 0 semupl 112 4 0 4 1 0 1 1 0 8 1 semapl 112 13 0 4 1 0 1 1 0 8 0 shmpl 112 12 0 0 1 0 1 1 0 8 0 dirhash 1024 21 0 4 3 0 3 3 0 8 0 dino2pl 256 2287 0 778 96 0 96 96 0 8 0 ffsino 288 2287 0 778 109 0 109 109 0 8 0 nchpl 144 3015 0 1322 63 0 63 63 0 8 0 rtmask 32 6 0 6 1 1 0 1 0 8 0 uvmvnodes 80 2588 0 0 53 0 53 53 0 8 0 vnodes 216 2588 0 0 144 0 144 144 0 8 0 namei 1024 9355 0 9355 2 1 1 2 0 8 1 percpumem 16 72 0 25 1 0 1 1 0 8 0 kstatmem 264 52 0 28 3 1 2 3 0 8 0 scsiplug 72 1 0 1 1 0 1 1 0 8 1 scxspl 216 9449 0 9447 10 3 7 8 1 8 6 plimitpl 152 133 0 115 1 0 1 1 0 8 0 sigapl 424 802 0 751 8 2 6 7 0 8 0 futexpl 64 6099 0 6093 1 0 1 1 0 8 0 knotepl 120 319 0 0 10 0 10 10 0 8 0 kqueuepl 224 202 0 191 4 1 3 3 0 8 2 pipepl 336 140 0 113 3 0 3 3 0 8 0 fdescpl 520 782 0 751 3 0 3 3 0 8 0 filepl 160 4011 0 3751 13 0 13 13 0 8 1 lockfpl 104 173 0 170 1 0 1 1 0 8 0 lockfspl 48 52 0 49 1 0 1 1 0 8 0 sessionpl 144 22 0 13 1 0 1 1 0 8 0 pgrppl 48 33 0 16 1 0 1 1 0 8 0 ucredpl 104 382 0 367 1 0 1 1 0 8 0 zombiepl 144 752 0 751 1 0 1 1 0 8 0 processpl 1192 802 0 751 5 0 5 5 0 8 0 procpl 656 1442 0 1378 7 1 6 6 0 8 0 srpgc 96 2 0 2 1 0 1 1 0 8 1 sosppl 168 5 0 5 1 0 1 1 0 8 1 sockpl 728 994 0 924 10 1 9 10 0 8 2 mcl64k 65536 4 0 0 1 0 1 1 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 1 0 0 1 0 1 1 0 8 0 mcl8k 8192 3 0 0 1 0 1 1 0 8 0 mcl4k 4096 121 0 0 16 0 16 16 0 8 0 mcl2k 2048 26 0 0 4 0 4 4 0 8 0 mtagpl 96 23 0 0 1 0 1 1 0 8 0 mbufpl 256 264 0 0 17 0 17 17 0 8 0 bufpl 280 3034 0 124 208 0 208 208 0 8 0 anonpl 32 5535 0 0 45 0 45 45 0 246 0 amapchunkpl 152 19307 0 18786 27 2 25 26 0 158 4 amappl16 200 2118 0 2085 5 3 2 5 0 8 0 amappl15 192 4 0 4 1 1 0 1 0 8 0 amappl14 184 113 0 101 1 0 1 1 0 8 0 amappl13 176 9 0 9 1 1 0 1 0 8 0 amappl12 168 1419 0 1388 4 1 3 3 0 8 0 amappl11 160 72 0 58 1 0 1 1 0 8 0 amappl10 152 9 0 9 1 1 0 1 0 8 0 amappl9 144 246 0 246 1 1 0 1 0 8 0 amappl8 136 25 0 22 1 0 1 1 0 8 0 amappl7 128 110 0 98 1 0 1 1 0 8 0 amappl6 120 179 0 176 1 0 1 1 0 8 0 amappl5 112 121 0 112 1 0 1 1 0 8 0 amappl4 104 313 0 293 1 0 1 1 0 8 0 amappl3 96 3674 0 3555 5 1 4 4 0 8 1 amappl2 88 635 0 573 2 0 2 2 0 8 0 amappl1 80 9760 0 9156 16 3 13 16 0 8 0 amappl 88 5359 0 5184 5 0 5 5 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 7 0 7 2 2 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 14 0 0 1 0 1 1 0 8 0 uaddrrnd 24 782 0 751 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 782 0 751 1 0 1 1 0 8 0 vmmpekpl 168 7884 0 7851 2 0 2 2 0 8 0 vmmpepl 168 54217 0 52212 92 2 90 92 0 357 0 vmsppl 480 781 0 751 5 1 4 5 0 8 0 rwobjpl 72 18770 0 15223 65 0 65 65 0 8 0 pdppl 4096 1572 0 1502 96 24 72 86 0 8 2 pvpl 32 13366 0 0 108 0 108 108 0 265 0 pmappl 256 781 0 751 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 394 0 30 11 0 11 11 0 8 0 ddb{0}> machine ddbcpu 0 Invalid cpu 0 ddb{0}> trace db_enter() at db_enter+0x25 sys/arch/amd64/amd64/db_interface.c:438 panic(ffffffff833e3610) at panic+0x1e5 sys/kern/subr_prf.c:198 mtx_enter_try(ffffffff8396b418) at mtx_enter_try+0x1bf sys/kern/kern_lock.c:271 mtx_enter(ffffffff8396b418) at mtx_enter+0x60 sys/kern/kern_lock.c:239 uvm_pageclean(fffffd8008290aa0) at uvm_pageclean+0x290 uvm_pagedequeue sys/uvm/uvm_page.c:-1 [inline] uvm_pageclean(fffffd8008290aa0) at uvm_pageclean+0x290 sys/uvm/uvm_page.c:980 uvm_pagefree(fffffd8008290aa0) at uvm_pagefree+0x26 sys/uvm/uvm_page.c:1020 uvn_get(fffffd805f4daa88,0,ffff8000307e82e8,ffff8000307e82c4,0,2,e3d35ed173bef778,ffff8000307e8540) at uvn_get+0x68b sys/uvm/uvm_vnode.c:1118 uvm_fault_lower_io(ffff8000307e8508,ffff8000307e8540,ffff8000307e8370,ffff8000307e8378) at uvm_fault_lower_io+0x319 sys/uvm/uvm_fault.c:1588 uvm_fault_lower(ffff8000307e8508,ffff8000307e8540,ffff8000307e8480) at uvm_fault_lower+0x278 sys/uvm/uvm_fault.c:1362 uvm_fault(fffffd806bea3978,200000000000,0,2) at uvm_fault+0x272 sys/uvm/uvm_fault.c:-1 upageflttrap(ffff8000307e8690,200000000140) at upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:188 usertrap(ffff8000307e8690) at usertrap+0x2d8 sys/arch/amd64/amd64/trap.c:436 recall_trap() at recall_trap+0x8 end of kernel end trace frame: 0x71383e1a8680, count: -13 ddb{0}> machine ddbcpu 1 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffff8000299edff0) 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 end of kernel end trace frame: 0x77635d562c60, count: 12 ddb{1}> trace x86_ipi_db(ffff8000299edff0) 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 end of kernel end trace frame: 0x77635d562c60, count: -3