panic: uvm_fault_unwire_locked: addWArReNsIsN noGt: iSnP Lm NaOTp LSOtWERarED OtNi nSgY SCstaALcL k7 3tr 4a8c7e4.2.4. EXIT 0 c Stopped at savectx+0xae: movl $0,%gs:0x680 TID PID UID PRFLAGS PFLAGS CPU COMMAND 153064 12491 0 0 0x4000000 0K syz-executor *158875 12491 0 0 0x4000000 1 syz-executor savectx() at savectx+0xae end of kernel end trace frame: 0xae4942d9b50, count: 14 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 *cpu0: uvm_fault_unwire_locked: address not in map ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0xae4942d9b50, count: -1 ddb{1}> show registers rdi 0 rsi 0 rbp 0xffff80003c5ad1b0 rbx 0 rdx 0xffff800001480480 rcx 0xffff80003c5a67f0 rax 0x37 r8 0xffff80003c5ad0e0 r9 0 r10 0x702fc9cacf63ace0 r11 0x47097f5962b09784 r12 0 r13 0 r14 0xffff80003c5a67f0 r15 0 rip 0xffffffff82eb53ee savectx+0xae cs 0x8 rflags 0x46 rsp 0xffff80003c5ad130 ss 0 savectx+0xae: movl $0,%gs:0x680 ddb{1}> show proc PROC (syz-executor) tid=158875 pid=12491 tcnt=3 stat=onproc flags process=0 proc=4000000 runpri=32, usrpri=86, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003c5a7c70,0xffffffff839c80c8 process=0xffff8000ffff04c0 user=0xffff80003c5a8000, vmspace=0xfffffd806bc853b0 estcpu=36, cpticks=0, pctcpu=0.0, user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 12491 144335 40156 0 2 0 syz-executor 12491 153064 40156 0 7 0x4000000 syz-executor *12491 158875 40156 0 7 0x4000000 syz-executor 55519 504453 27803 0 2 0x480 syz-executor 55519 362518 27803 0 3 0x4000080 kqpoll syz-executor 55519 474951 27803 0 3 0x4000080 fsleep syz-executor 11836 423749 67172 -1 3 0x90 nanoslp syz-executor 11836 166396 67172 -1 3 0x4000090 piperd syz-executor 11836 222018 67172 -1 3 0x4000090 fsleep syz-executor 73204 10690 62323 0 2 0x480 syz-executor 73204 86542 62323 0 3 0x4000080 fsleep syz-executor 73204 318056 62323 0 3 0x4000080 bell syz-executor 26585 351673 23751 0 2 0x480 syz-executor 26585 455516 23751 0 3 0x4000080 pipewr syz-executor 26585 364517 23751 0 3 0x4000080 fsleep syz-executor 16681 100655 0 0 3 0x14280 nfsidl nfsio 76273 77595 0 0 3 0x14280 nfsidl nfsio 87982 417732 0 0 3 0x14280 nfsidl nfsio 26803 53270 0 0 3 0x14280 nfsidl nfsio 52178 17701 0 0 3 0x14280 nfsidl nfsio 30270 508417 0 0 3 0x14280 nfsidl nfsio 32464 149573 0 0 3 0x14280 nfsidl nfsio 13142 61002 0 0 3 0x14280 nfsidl nfsio 21846 204781 0 0 3 0x14280 nfsidl nfsio 35931 465919 0 0 3 0x14280 nfsidl nfsio 53850 70338 0 0 3 0x14280 nfsidl nfsio 77236 96579 0 0 3 0x14280 nfsidl nfsio 11892 74294 0 0 3 0x14280 nfsidl nfsio 9673 409620 0 0 3 0x14280 nfsidl nfsio 87393 423508 0 0 3 0x14280 nfsidl nfsio 31105 119856 0 0 3 0x14280 nfsidl nfsio 76160 487375 0 0 3 0x14280 nfsidl nfsio 17727 227590 0 0 3 0x14280 nfsidl nfsio 14559 463319 0 0 3 0x14280 nfsidl nfsio 13835 462420 0 0 3 0x14280 nfsidl nfsio 24078 68537 0 0 3 0x14200 bored sosplice 27803 85034 72111 0 2 0x482 syz-executor 75673 163158 72111 0 3 0x82 nanoslp syz-executor 62323 256479 72111 0 2 0x482 syz-executor 67172 31174 72111 0 2 0x482 syz-executor 40156 252294 72111 0 3 0x82 nanoslp syz-executor 39860 332174 72111 0 2 0x482 syz-executor 40595 242393 72111 0 2 0x482 syz-executor 23751 337439 72111 0 2 0x482 syz-executor 72111 366328 58794 0 3 0x82 kqread syz-executor 58794 334034 90460 0 3 0x10008a sigsusp ksh 90460 84597 92947 0 3 0x98 kqread sshd-session 92947 331590 78375 0 3 0x92 kqread sshd-session 3030 259574 1 0 3 0x100083 ttyin getty 78375 33198 1 0 3 0x88 kqread sshd 32259 437369 42999 74 3 0x1100092 bpf pflogd 42999 100456 1 0 3 0x80 sbwait pflogd 35857 351216 86543 73 3 0x1100090 kqread syslogd 86543 40297 1 0 3 0x100082 sbwait syslogd 74199 484228 1 0 3 0x100080 kqread resolvd 6329 414378 36515 77 3 0x100092 kqread dhcpleased 12932 509254 36515 77 3 0x100092 kqread dhcpleased 36515 412795 1 0 3 0x80 kqread dhcpleased 2874 477394 0 0 3 0x14200 bored smr 4836 327457 0 0 3 0x14200 pgzero zerothread 76611 152775 0 0 3 0x14200 aiodoned aiodoned 11548 25044 0 0 3 0x14200 syncer update 8875 517472 0 0 3 0x14200 cleaner cleaner 61052 281906 0 0 3 0x14200 reaper reaper 16475 124620 0 0 3 0x14200 pgdaemon pagedaemon 31100 15859 0 0 3 0x14200 bored viomb 15585 442392 0 0 3 0x40014200 acpi0 acpi0 12577 376516 0 0 3 0x40014200 idle1 32111 77623 0 0 3 0x14200 bored softnet3 19452 112643 0 0 3 0x14200 bored softnet2 38055 42540 0 0 3 0x14200 bored softnet1 63203 143015 0 0 3 0x14200 bored softnet0 40566 452798 0 0 3 0x14200 bored systqmp 24604 241252 0 0 3 0x14200 bored systq 17822 233515 0 0 3 0x14200 tmoslp softclockmp 13479 522718 0 0 2 0x40014200 softclock 32797 487476 0 0 3 0x40014200 idle0 1 294866 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks CPU 1: exclusive mutex &sched_lock r = 0 (0xffffffff839ca2f8) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 mtx_enter_try+0x178 sys/kern/kern_lock.c:-1 #2 mtx_enter+0x60 sys/kern/kern_lock.c:239 #3 wakeup_n+0x54 sys/kern/kern_synch.c:580 #4 uvm_pmr_freepages+0x3fd sys/uvm/uvm_pmemrange.c:1337 #5 uvm_anfree_list+0x1e3 sys/uvm/uvm_anon.c:112 #6 amap_wiperange_chunk+0x1a8 sys/uvm/uvm_amap.c:983 #7 amap_pp_adjref+0x6f4 sys/uvm/uvm_amap.c:944 #8 amap_adjref_anons+0x22d sys/uvm/uvm_amap.c:1329 #9 uvm_unmap_detach+0x8a sys/uvm/uvm_map.c:1353 #10 sys_munmap+0x32f sys/uvm/uvm_mmap.c:544 #11 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #11 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #12 Xsyscall+0x128 exclusive mutex &uvm.fpageqlock r = 0 (0xffffffff8398c408) #0 witness_lock+0x5bb stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5bb sys/kern/subr_witness.c:1155 #1 mtx_enter_try+0x178 sys/kern/kern_lock.c:-1 #2 mtx_enter+0x60 sys/kern/kern_lock.c:239 #3 uvm_pmr_freepages+0x1a8 sys/uvm/uvm_pmemrange.c:1323 #4 uvm_anfree_list+0x1e3 sys/uvm/uvm_anon.c:112 #5 amap_wiperange_chunk+0x1a8 sys/uvm/uvm_amap.c:983 #6 amap_pp_adjref+0x6f4 sys/uvm/uvm_amap.c:944 #7 amap_adjref_anons+0x22d sys/uvm/uvm_amap.c:1329 #8 uvm_unmap_detach+0x8a sys/uvm/uvm_map.c:1353 #9 sys_munmap+0x32f sys/uvm/uvm_mmap.c:544 #10 syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] #10 syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 #11 Xsyscall+0x128 Process 12491 (syz-executor) thread 0xffff80003c5a7c70 (153064) Process 12491 (syz-executor) thread 0xffff80003c5a67f0 (158875) ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10191 11031K 11301K 166960K 11627 0 pcb 17 14K 16K 166960K 158 0 rtable 190 6K 7K 166960K 372 0 pf 33 17K 22K 166960K 73 0 ifaddr 38 6K 7K 166960K 56 0 ifgroup 51 2K 2K 166960K 75 0 sysctl 2 1K 1K 166960K 2 0 counters 62 36K 37K 166960K 86 0 ioctlops 0 0K 4K 166960K 1530 0 iov 1 1K 16K 166960K 19 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1366 86K 86K 166960K 1699 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 12 0K 0K 166960K 41 0 dirhash 12 2K 2K 166960K 27 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 93K 166960K 537 0 sigio 0 0K 0K 166960K 4 0 proc 73 103K 140K 166960K 570 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 61 0 in_multi 87 6K 7K 166960K 111 0 ether_multi 1 0K 0K 166960K 1 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 61 281K 281K 166960K 61 0 exec 0 0K 1K 166960K 426 0 fusefs mount 1 32K 32K 166960K 1 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 252 168K 185K 166960K 6399 0 UVM aobj 14 2K 4K 166960K 16 0 pinsyscall 43 86K 102K 166960K 1625 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 31 0 NDP 11 0K 2K 166960K 35 0 temp 76 8692K 8768K 166960K 12598 0 kqueue 14 22K 28K 166960K 86 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 66 0 63 1 0 1 1 0 8 0 rtentry 168 115 0 29 5 0 5 5 0 8 0 unpcb 144 369 0 346 6 0 6 6 0 8 5 syncache 336 5 0 5 2 1 1 1 0 8 1 tcpqe 32 1 0 1 1 0 1 1 0 8 1 tcpcb 808 291 0 285 8 0 8 8 0 8 7 arp 120 18 0 4 1 0 1 1 0 8 0 inpcb 376 680 0 669 22 13 9 22 0 8 7 nd6 136 25 0 3 1 0 1 1 0 8 0 pkpcb 40 2 0 2 1 1 0 1 0 8 0 kcovpl 48 8 0 0 1 0 1 1 0 8 0 ppxss 1168 9 0 9 1 0 1 1 0 8 1 pppxif 1480 1 0 1 1 1 0 1 0 8 0 pffrag 232 3 0 0 1 0 1 1 0 482 0 pffrnode 88 3 0 0 1 0 1 1 0 8 0 pffrent 40 3 0 0 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 pfanchor 1288 1 0 0 1 0 1 1 0 8 0 pftag 88 1 0 1 1 1 0 1 0 8 0 pfstitem 24 39 0 1 1 0 1 1 0 8 0 pfstkey 128 39 0 1 2 0 2 2 0 8 0 pfstate 376 39 0 1 4 0 4 4 0 8 0 pfrule 1344 24 0 19 2 1 1 2 0 8 0 art_heap8 4096 1 0 0 1 0 1 1 0 8 0 art_heap4 256 491 0 95 29 0 29 29 0 8 1 art_table 32 492 0 95 4 0 4 4 0 8 0 art_node 16 113 0 36 1 0 1 1 0 8 0 sysvmsgpl 40 5 0 0 1 0 1 1 0 8 0 semupl 112 1 0 1 1 1 0 1 0 8 0 semapl 112 38 0 28 1 0 1 1 0 8 0 shmpl 112 13 0 2 1 0 1 1 0 8 0 dirhash 1024 27 0 10 3 0 3 3 0 8 0 dino2pl 256 2382 0 875 95 0 95 95 0 8 0 ffsino 280 2382 0 875 109 0 109 109 0 8 0 nchpl 144 3150 0 1454 64 0 64 64 0 8 0 rtmask 32 1 0 1 1 0 1 1 0 8 1 uvmvnodes 80 2624 0 0 54 0 54 54 0 8 0 vnodes 216 2624 0 0 146 0 146 146 0 8 0 namei 1024 10287 0 10287 2 1 1 2 0 8 1 percpumem 16 57 0 12 1 0 1 1 0 8 0 kstatmem 264 38 0 16 2 0 2 2 0 8 0 scsiplug 72 1 0 1 1 1 0 1 0 8 0 scxspl 216 9414 0 9414 3 2 1 2 1 8 1 plimitpl 152 76 0 59 1 0 1 1 0 8 0 sigapl 424 859 0 788 11 2 9 9 0 8 0 futexpl 64 6453 0 6449 1 0 1 1 0 8 0 knotepl 120 325 0 0 10 0 10 10 0 8 0 kqueuepl 216 219 0 207 5 0 5 5 0 8 4 pipepl 328 192 0 163 3 0 3 3 0 8 0 fdescpl 504 819 0 787 5 0 5 5 0 8 0 filepl 152 4691 0 4453 20 0 20 20 0 8 8 lockfpl 104 143 0 141 1 0 1 1 0 8 0 lockfspl 48 60 0 58 1 0 1 1 0 8 0 sessionpl 144 24 0 15 1 0 1 1 0 8 0 pgrppl 48 34 0 17 1 0 1 1 0 8 0 ucredpl 104 579 0 564 1 0 1 1 0 8 0 zombiepl 144 791 0 788 1 0 1 1 0 8 0 processpl 1176 859 0 788 6 0 6 6 0 8 0 procpl 656 1545 0 1464 9 1 8 8 0 8 0 srpgc 96 2 0 2 1 0 1 1 0 8 1 sosppl 168 13 0 11 1 0 1 1 0 8 0 sockpl 688 1154 0 1117 25 14 11 22 0 8 7 mcl64k 65536 2 0 0 1 0 1 1 0 8 0 mcl8k 8192 2 0 0 1 0 1 1 0 8 0 mcl4k 4096 128 0 0 16 0 16 16 0 8 0 mcl2k 2048 22 0 0 3 0 3 3 0 8 0 mtagpl 96 8 0 0 1 0 1 1 0 8 0 mbufpl 256 315 0 0 20 0 20 20 0 8 0 bufpl 280 2961 0 129 203 0 203 203 0 8 0 anonpl 24 108017 0 104399 46 0 46 46 0 184 21 amapchunkpl 152 19736 0 19205 27 1 26 27 0 158 5 amappl16 200 1413 0 1369 16 5 11 15 0 8 8 amappl15 192 2 0 2 1 1 0 1 0 8 0 amappl14 184 113 0 101 1 0 1 1 0 8 0 amappl13 176 2 0 2 1 1 0 1 0 8 0 amappl12 168 1489 0 1457 3 1 2 2 0 8 0 amappl11 160 129 0 115 1 0 1 1 0 8 0 amappl10 152 6 0 6 1 1 0 1 0 8 0 amappl9 144 261 0 261 1 1 0 1 0 8 0 amappl8 136 23 0 20 1 0 1 1 0 8 0 amappl7 128 149 0 137 1 0 1 1 0 8 0 amappl6 120 172 0 169 1 0 1 1 0 8 0 amappl5 112 179 0 168 1 0 1 1 0 8 0 amappl4 104 314 0 295 1 0 1 1 0 8 0 amappl3 96 3944 0 3821 4 0 4 4 0 8 0 amappl2 88 637 0 576 2 0 2 2 0 8 0 amappl1 80 10284 0 9678 16 1 15 15 0 8 0 amappl 88 5648 0 5471 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 6 0 6 1 1 0 1 0 8 0 dma32 32 40 0 40 2 1 1 1 0 8 1 dma16 16 18 0 17 1 0 1 1 0 8 0 aobjpl 72 15 0 2 1 0 1 1 0 8 0 uaddrrnd 24 819 0 787 1 0 1 1 0 8 0 uaddrbest 32 2 0 0 1 0 1 1 0 8 0 uaddr 24 819 0 787 1 0 1 1 0 8 0 vmmpekpl 168 8267 0 8229 2 0 2 2 0 8 0 vmmpepl 168 56367 0 54317 100 1 99 99 0 357 6 vmsppl 456 818 0 787 5 0 5 5 0 8 1 rwobjpl 64 18884 0 15285 59 0 59 59 0 8 0 pdppl 4096 1645 0 1574 97 24 73 85 0 8 2 pvpl 32 14859 0 0 122 2 120 121 0 265 0 pmappl 248 818 0 787 3 0 3 3 0 8 0 extentpl 40 45 0 27 1 0 1 1 0 8 0 phpool 112 288 0 29 8 0 8 8 0 8 0 ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8385aff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c kd_curproc sys/dev/kcov.c:584 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c sys/dev/kcov.c:153 db_elf_sym_search(ffffffff81341d00,0,ffff800038ccbd80) at db_elf_sym_search+0xbf sys/ddb/db_elf.c:290 db_search_symbol(ffffffff81341d00,0,ffff800038ccbdf0) at db_search_symbol+0x52 sys/ddb/db_sym.c:106 db_stack_trace_print(ffff800038ccbec0,1,100,ffffffff83384624,ffffffff81342320) at db_stack_trace_print+0x2fe sys/arch/amd64/amd64/db_trace.c:147 db_stack_dump() at db_stack_dump+0xa5 sys/ddb/db_output.c:243 panic(ffffffff8341f3cd) at panic+0x1d0 sys/kern/subr_prf.c:229 uvm_fault_unwire_locked(fffffd806bc853b0,2000002f0000,200000300000) at uvm_fault_unwire_locked+0x4ed uvm_fault_wire(fffffd806bc853b0,2000002f0000,200000301000,1) at uvm_fault_wire+0x12d uvm_fault_unwire sys/uvm/uvm_fault.c:1702 [inline] uvm_fault_wire(fffffd806bc853b0,2000002f0000,200000301000,1) at uvm_fault_wire+0x12d sys/uvm/uvm_fault.c:1684 uvm_vslock_device(ffff80003c5a7c70,2000002f04c0,10000,1,ffff800038ccc180) at uvm_vslock_device+0x112 sys/uvm/uvm_glue.c:169 physio(ffffffff821cc7c0,d02,0,ffffffff821cd020,ffff800038ccc448) at physio+0x277 sys/kern/kern_physio.c:139 spec_write(ffff800038ccc2a0) at spec_write+0x120 sys/kern/spec_vnops.c:302 end trace frame: 0xffff800038ccc310, count: 0 ddb{0}> trace x86_ipi_db(ffffffff8385aff0) 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 __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c kd_curproc sys/dev/kcov.c:584 [inline] __sanitizer_cov_trace_pc() at __sanitizer_cov_trace_pc+0x2c sys/dev/kcov.c:153 db_elf_sym_search(ffffffff81341d00,0,ffff800038ccbd80) at db_elf_sym_search+0xbf sys/ddb/db_elf.c:290 db_search_symbol(ffffffff81341d00,0,ffff800038ccbdf0) at db_search_symbol+0x52 sys/ddb/db_sym.c:106 db_stack_trace_print(ffff800038ccbec0,1,100,ffffffff83384624,ffffffff81342320) at db_stack_trace_print+0x2fe sys/arch/amd64/amd64/db_trace.c:147 db_stack_dump() at db_stack_dump+0xa5 sys/ddb/db_output.c:243 panic(ffffffff8341f3cd) at panic+0x1d0 sys/kern/subr_prf.c:229 uvm_fault_unwire_locked(fffffd806bc853b0,2000002f0000,200000300000) at uvm_fault_unwire_locked+0x4ed uvm_fault_wire(fffffd806bc853b0,2000002f0000,200000301000,1) at uvm_fault_wire+0x12d uvm_fault_unwire sys/uvm/uvm_fault.c:1702 [inline] uvm_fault_wire(fffffd806bc853b0,2000002f0000,200000301000,1) at uvm_fault_wire+0x12d sys/uvm/uvm_fault.c:1684 uvm_vslock_device(ffff80003c5a7c70,2000002f04c0,10000,1,ffff800038ccc180) at uvm_vslock_device+0x112 sys/uvm/uvm_glue.c:169 physio(ffffffff821cc7c0,d02,0,ffffffff821cd020,ffff800038ccc448) at physio+0x277 sys/kern/kern_physio.c:139 spec_write(ffff800038ccc2a0) at spec_write+0x120 sys/kern/spec_vnops.c:302 VOP_WRITE(fffffd806bc3c958,ffff800038ccc448,5,fffffd807f7d3340) at VOP_WRITE+0x102 sys/kern/vfs_vops.c:245 vn_write(fffffd805fb19d10,ffff800038ccc448,0) at vn_write+0x1d4 sys/kern/vfs_vnops.c:408 dofilewritev(ffff80003c5a7c70,7,ffff800038ccc448,0,ffff800038ccc500) at dofilewritev+0x23c sys/kern/sys_generic.c:380 sys_write(ffff80003c5a7c70,ffff800038ccc5b0,ffff800038ccc500) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff800038ccc5b0) at syscall+0xbc6 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800038ccc5b0) at syscall+0xbc6 sys/arch/amd64/amd64/trap.c:577 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xae437746a50, 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: 0xae4942d9b50, count: 14 ddb{1}> trace savectx() at savectx+0xae end of kernel end trace frame: 0xae4942d9b50, count: -1