uvm_fault(0xffffffff839dd398, 0xffff800001765000, 0, 2) -> e kernel: page fault trap, code=2 Stopped at sys_shmat+0xe0: movl $0xffffffffffffffff,0(%r14) TID PID UID PRFLAGS PFLAGS CPU COMMAND *104778 11715 0 0x10 0x4000000 1K syz-executor 94078 3936 0 0x2 0x1 0 syz-executor sys_shmat(ffff8000fffee7e0,ffff80002a3ae710,ffff80002a3ae660) at sys_shmat+0xe0 sys/kern/sysv_shm.c:235 syscall(ffff80002a3ae710) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3ae710) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8127187f5d0, count: 12 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: uvm_fault(0xffffffff839dd398, 0xffff800001765000, 0, 2) -> e ddb{1}> trace sys_shmat(ffff8000fffee7e0,ffff80002a3ae710,ffff80002a3ae660) at sys_shmat+0xe0 sys/kern/sysv_shm.c:235 syscall(ffff80002a3ae710) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3ae710) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8127187f5d0, count: -3 ddb{1}> show registers rdi 0xffff80002abd0000 rsi 0x18ccf acpi_pdirpa+0x4b40 rbp 0xffff80002a3ae630 rbx 0xffff80002a3ae710 rdx 0xffff80002abd0000 rcx 0x18cce acpi_pdirpa+0x4b3f rax 0xffffffff823f7302 sys_shmat+0xf2 r8 0x2080713 __kernel_phys_base+0x1080713 r9 0x1 r10 0 r11 0xd49c9fa68a0164d8 r12 0xffff8000fffee7e0 r13 0xffff8000015db000 r14 0xffff800001765000 r15 0x18a00 acpi_pdirpa+0x4871 rip 0xffffffff823f72f0 sys_shmat+0xe0 cs 0x8 rflags 0x10216 __ALIGN_SIZE+0xf216 rsp 0xffff80002a3ae5a0 ss 0x10 sys_shmat+0xe0: movl $0xffffffffffffffff,0(%r14) ddb{1}> show proc PROC (syz-executor) tid=104778 pid=11715 tcnt=4 stat=onproc flags process=10 proc=4000000 runpri=86, usrpri=86, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff8000333e14f0,0xffff8000fffee558 process=0xffff80003c42ab78 user=0xffff80002a3a9000, vmspace=0xfffffd806aa10b90 estcpu=36, cpticks=1, pctcpu=0.0, user=0, sys=1, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 16308 447274 10870 0 2 0 syz-executor 42590 133678 3936 0 2 0 syz-executor 52617 461000 53883 0 2 0 syz-executor 52617 481141 53883 0 3 0x4000080 fsleep syz-executor 52617 449637 53883 0 2 0x4000000 syz-executor 30359 405526 81413 0 3 0 vmmaplk syz-executor 30359 150602 81413 0 2 0x4000000 syz-executor 30359 314097 81413 0 3 0x4000000 vmmaplk syz-executor 82912 37429 57796 60928 2 0x10 syz-executor 82912 149463 57796 60928 2 0x4000010 syz-executor 82912 166129 57796 60928 3 0x4000090 fsleep syz-executor 71045 307201 48171 0 2 0 syz-executor 71045 499404 48171 0 3 0x4000080 fsleep syz-executor 71045 18985 48171 0 3 0x4000080 fsleep syz-executor 11715 405483 98711 0 2 0x10 syz-executor 11715 87132 98711 0 3 0x4000090 fsleep syz-executor *11715 104778 98711 0 7 0x4000010 syz-executor 11715 305489 98711 0 3 0x4000090 fsleep syz-executor 47859 192899 43878 0 2 0x2 syz-executor 10870 352515 43878 0 3 0x82 nanoslp syz-executor 3936 94078 43878 0 7 0x3 syz-executor 22255 230271 0 0 3 0x14200 bored sosplice 71491 490870 0 0 3 0x14280 nfsidl nfsio 81383 464565 0 0 3 0x14280 nfsidl nfsio 24057 136372 0 0 3 0x14280 nfsidl nfsio 32621 272436 0 0 3 0x14280 nfsidl nfsio 61839 523547 0 0 3 0x14280 nfsidl nfsio 26256 102418 0 0 3 0x14280 nfsidl nfsio 63140 77439 0 0 3 0x14280 nfsidl nfsio 13308 513639 0 0 3 0x14280 nfsidl nfsio 31994 333867 0 0 3 0x14280 nfsidl nfsio 58953 310520 0 0 3 0x14280 nfsidl nfsio 29449 33306 0 0 3 0x14280 nfsidl nfsio 54183 136410 0 0 3 0x14280 nfsidl nfsio 33386 68770 0 0 3 0x14280 nfsidl nfsio 12803 311951 0 0 3 0x14280 nfsidl nfsio 39407 43794 0 0 3 0x14280 nfsidl nfsio 47976 245684 0 0 3 0x14280 nfsidl nfsio 30853 281525 0 0 3 0x14280 nfsidl nfsio 90554 64033 0 0 3 0x14280 nfsidl nfsio 61012 136424 0 0 3 0x14280 nfsidl nfsio 71860 252405 0 0 3 0x14280 nfsidl nfsio 53883 4363 43878 0 3 0x82 nanoslp syz-executor 81413 494670 43878 0 3 0x82 nanoslp syz-executor 48171 499834 43878 0 3 0x82 nanoslp syz-executor 57796 199615 43878 0 3 0x82 nanoslp syz-executor 98711 158481 43878 0 2 0x2 syz-executor 43878 432771 96844 0 3 0x82 kqread syz-executor 96844 429210 47241 0 3 0x10008a sigsusp ksh 47241 237612 169 0 3 0x98 kqread sshd-session 169 70150 26029 0 3 0x92 kqread sshd-session 54054 414993 1 0 3 0x100083 ttyin getty 26029 318372 1 0 3 0x88 kqread sshd 22127 182684 84070 74 3 0x1100092 bpf pflogd 84070 322115 1 0 3 0x80 sbwait pflogd 72326 78301 81935 73 3 0x1100090 kqread syslogd 81935 196635 1 0 3 0x100082 sbwait syslogd 17868 20179 1 0 3 0x100080 kqread resolvd 90356 344447 70266 77 3 0x100092 kqread dhcpleased 2923 84866 70266 77 3 0x100092 kqread dhcpleased 70266 114229 1 0 3 0x80 kqread dhcpleased 4892 371426 0 0 3 0x14200 bored smr 68583 362583 0 0 2 0x14200 zerothread 78258 3273 0 0 3 0x14200 aiodoned aiodoned 62154 164923 0 0 3 0x14200 syncer update 68538 100328 0 0 3 0x14200 cleaner cleaner 52134 134202 0 0 3 0x14200 reaper reaper 33658 40247 0 0 3 0x14200 pgdaemon pagedaemon 38680 316898 0 0 3 0x14200 bored viomb 12013 164220 0 0 3 0x40014200 acpi0 acpi0 21235 155466 0 0 3 0x40014200 idle1 9589 164771 0 0 3 0x14200 bored softnet1 46042 99448 0 0 3 0x14200 bored softnet0 23366 428385 0 0 3 0x14200 bored systqmp 26530 25973 0 0 3 0x14200 bored systq 30140 46668 0 0 3 0x14200 tmoslp softclockmp 26794 500071 0 0 3 0x40014200 tmoslp softclock 50131 317456 0 0 3 0x40014200 idle0 1 426233 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 16308 (syz-executor) thread 0xffff80003c44e7f0 (447274) exclusive rwlock vmmaplk r = 0 (0xfffffd806b967e70) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x3e8 sys/kern/kern_rwlock.c:413 #2 uvmfault_lookup+0x122 sys/uvm/uvm_fault.c:1902 #3 uvm_fault_check+0x4f sys/uvm/uvm_fault.c:699 #4 uvm_fault+0x106 sys/uvm/uvm_fault.c:633 #5 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:192 #6 usertrap+0x3c6 sys/arch/amd64/amd64/trap.c:605 #7 recall_trap+0x8 Process 52617 (syz-executor) thread 0xffff8000fffef770 (449637) exclusive rwlock vmmaplk r = 0 (0xfffffd806aa10308) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_read+0x3e8 sys/kern/kern_rwlock.c:413 #2 uvmfault_lookup+0x122 sys/uvm/uvm_fault.c:1902 #3 uvm_fault_check+0x4f sys/uvm/uvm_fault.c:699 #4 uvm_fault+0x106 sys/uvm/uvm_fault.c:633 #5 upageflttrap+0xa9 sys/arch/amd64/amd64/trap.c:192 #6 usertrap+0x3c6 sys/arch/amd64/amd64/trap.c:605 #7 recall_trap+0x8 Process 30359 (syz-executor) thread 0xffff8000333e14f0 (150602) exclusive rwlock vmmaplk r = 0 (0xfffffd806aa108c0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 vm_map_lock_ln+0x12e sys/uvm/uvm_map.c:5171 #3 uvm_map_pageable+0x183 sys/uvm/uvm_map.c:2214 #4 sys_mlock+0x23d sys/uvm/uvm_mmap.c:849 #5 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #5 syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 #6 Xsyscall+0x128 Process 82912 (syz-executor) thread 0xffff80003c44e028 (149463) exclusive rwlock unix r = 0 (0xffff800001511ae0) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 rw_do_enter_write+0x419 sys/kern/kern_rwlock.c:320 #2 socreate+0x214 pru_attach sys/sys/protosw.h:-1 [inline] #2 socreate+0x214 sys/kern/uipc_socket.c:219 #3 sys_socketpair+0xcc sys/kern/uipc_syscalls.c:476 #4 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #4 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:748 #5 Xsyscall+0x128 Process 11715 (syz-executor) thread 0xffff8000fffee7e0 (104778) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff8388fdf8) #0 witness_lock+0x5f1 stacktrace_save sys/sys/stacktrace.h:37 [inline] #0 witness_lock+0x5f1 sys/kern/subr_witness.c:1160 #1 __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 #2 malloc+0xe3 sys/kern/kern_malloc.c:174 #3 sys_shmat+0x8f sys/kern/sysv_shm.c:-1 #4 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #4 syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 #5 Xsyscall+0x128 ddb{1}> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 10218 11028K 12377K 166960K 13404 0 pcb 17 15K 16K 166960K 307 0 rtable 169 10K 11K 166960K 892 0 pf 34 18K 67486K 166960K 418 0 ifaddr 33 7K 9K 166960K 239 0 ifgroup 49 2K 3K 166960K 407 0 sysctl 4 1K 9K 166960K 16 0 counters 62 36K 38K 166960K 390 0 ioctlops 0 0K 4K 166960K 1920 0 iov 0 0K 18K 166960K 161 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1483 93K 94K 166960K 2874 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 3 620K 620K 166960K 24 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 0K 166960K 105 0 dirhash 12 2K 2K 166960K 36 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 17 61K 236K 166960K 1860 0 sigio 1 0K 0K 166960K 107 0 proc 73 115K 164K 166960K 1032 0 subproc 67 4K 4K 166960K 202 0 NFS srvsock 1 0K 0K 166960K 1 0 NFS daemon 1 16K 16K 166960K 1 0 ip_moptions 0 0K 0K 166960K 211 0 in_multi 70 5K 7K 166960K 325 0 ether_multi 1 0K 0K 166960K 17 0 mrt 1 0K 0K 166960K 14 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 889 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 2 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 242 169K 187K 166960K 18049 0 UVM aobj 38 5K 5K 166960K 44 0 pinsyscall 42 84K 101K 166960K 3361 0 memdesc 1 4K 4K 166960K 1 0 crypto data 1 1K 1K 166960K 1 0 ip6_options 0 0K 0K 166960K 107 0 NDP 9 0K 2K 166960K 187 0 temp 78 8656K 8906K 166960K 78492 0 kqueue 13 20K 32K 166960K 371 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 120 231 0 228 3 2 1 3 0 8 0 rtentry 176 363 0 302 5 0 5 5 0 8 0 unpcb 144 1241 0 1222 17 15 2 6 0 8 1 syncache 336 13 0 13 5 4 1 1 0 8 1 tcpqe 32 12 0 12 5 4 1 1 0 8 1 tcpcb 736 444 0 433 5 3 2 5 0 8 0 pool(tcpcb): free list modified: page 0xffff80000165a000; item ordinal 0; addr 0xffff80000165a2e8 (p 0xfffffd8076cc0000); offset 0x8=0xffffffff tcpcb: pool(0xffffffff83898be8:tcpcb): page inconsistency: page 0xffff80000165a000; item ordinal 1; addr 0xffff80009cb79ebc arp 136 64 0 56 1 0 1 1 0 8 0 inpcb 328 1695 0 1681 18 16 2 7 0 8 0 nd6 152 50 0 38 1 0 1 1 0 8 0 pkpcb 40 17 0 17 7 6 1 1 0 8 1 kcovpl 48 22 0 15 1 0 1 1 0 8 0 mppekey 1024 5 0 5 4 3 1 1 0 8 1 ppxss 1192 127 0 127 2 1 1 1 0 8 1 pppxif 1504 9 0 9 3 3 0 1 0 8 0 pfstscr 40 3 0 3 2 2 0 1 0 8 0 pffrag 232 12 0 6 1 0 1 1 0 482 0 pffrnode 88 12 0 6 1 0 1 1 0 8 0 pffrent 40 24 0 18 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 96 0 64 1 0 1 1 0 8 0 pfstkey 128 108 0 76 2 0 2 2 0 8 0 pfstate 384 101 0 70 5 0 5 5 0 8 0 pfrule 1344 24 0 18 2 1 1 2 0 8 0 rttmr 136 1 0 1 1 1 0 1 0 8 0 art_heap8 4096 2 0 0 2 0 2 2 0 8 0 art_heap4 256 1405 0 1102 37 9 28 31 0 8 4 art_table 40 1407 0 1102 5 0 5 5 0 8 0 art_node 32 359 0 307 2 0 2 2 0 8 0 sysvmsgpl 40 21 0 14 1 0 1 1 0 8 0 semupl 112 2 0 2 1 1 0 1 0 8 0 semapl 112 102 0 92 1 0 1 1 0 8 0 shmpl 112 41 0 6 1 0 1 1 0 8 0 dirhash 1024 33 0 16 3 0 3 3 0 8 0 dino2pl 256 4631 0 3098 97 0 97 97 0 8 0 ffsino 296 4631 0 3098 120 1 119 119 0 8 0 nchpl 144 6943 0 5210 65 0 65 65 0 8 0 rtmask 32 9 0 9 5 5 0 1 0 8 0 vnodes 216 5496 0 0 306 0 306 306 0 8 0 namei 1024 25279 0 25279 6 5 1 3 0 8 1 percpumem 16 210 0 164 1 0 1 1 0 8 0 kstatmem 264 288 0 268 4 2 2 3 0 8 0 acpiwqpl 32 1 0 1 1 0 1 1 1 8 1 scsiplug 72 8 0 8 3 3 0 1 0 8 0 scxspl 216 52120 0 52120 12 10 2 8 1 8 2 plimitpl 152 547 0 530 1 0 1 1 0 8 0 sigapl 424 2146 0 2078 10 1 9 9 0 8 1 knotepl 120 628 0 0 17 0 17 17 0 8 0 kqueuepl 224 1074 0 1065 21 19 2 5 0 8 1 pipepl 344 384 0 357 4 1 3 4 0 8 0 fdescpl 528 2105 0 2074 3 0 3 3 0 8 0 filepl 160 13480 0 13275 34 22 12 16 0 8 1 lockfpl 104 650 0 647 2 1 1 2 0 8 0 lockfspl 48 209 0 206 1 0 1 1 0 8 0 sessionpl 144 45 0 36 1 0 1 1 0 8 0 pgrppl 48 87 0 70 1 0 1 1 0 8 0 ucredpl 104 2408 0 2393 1 0 1 1 0 8 0 zombiepl 144 2837 0 2837 1 0 1 1 0 8 1 processpl 1232 2146 0 2078 6 0 6 6 0 8 0 procpl 664 4964 0 4885 9 1 8 8 0 8 0 sosppl 168 8 0 8 3 3 0 1 0 8 0 sockpl 752 3370 0 3334 49 39 10 18 0 8 4 sockpl: pool(0xffffffff83952b58:sockpl): page inconsistency: page 0xffff8000ffffffff; at page head addr 0xffff80000166df90 (p 0xffff80000166c000) uvm_fault(0xffffffff839dd398, 0xffff80010000004f, 0, 1) -> e kernel: page fault trap, code=0 Faulted in DDB; continuing... ddb{1}> machine ddbcpu 0 Stopped at x86_ipi_db+0x27: addq $0x8,%rsp x86_ipi_db(ffffffff8378fff0) 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 __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff8388fbf0,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 rw_do_enter_write(fffffd806bbdf688,1) at rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298 rrw_enter(fffffd806bbdf688,1) at rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 VOP_LOCK(fffffd8069b2caf8,2001) at VOP_LOCK+0xa3 sys/kern/vfs_vops.c:527 vn_lock(fffffd8069b2caf8,2001) at vn_lock+0xa4 sys/kern/vfs_vnops.c:570 end trace frame: 0xffff80003a8a1c80, count: 0 ddb{0}> trace x86_ipi_db(ffffffff8378fff0) 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 __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 sys/kern/kern_lock.c:165 softintr_dispatch(0) at softintr_dispatch+0x125 sys/kern/kern_softintr.c:83 dosoftint(0) at dosoftint+0x54 sys/arch/amd64/amd64/intr.c:847 Xsoftclock() at Xsoftclock+0x27 __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 __mp_lock_spin sys/kern/kern_lock.c:134 [inline] __mp_lock(ffffffff8388fbf0) at __mp_lock+0x192 sys/kern/kern_lock.c:165 __mp_acquire_count(ffffffff8388fbf0,1) at __mp_acquire_count+0x58 sys/kern/kern_lock.c:-1 sleep_finish(ffffffffffffffff,1) at sleep_finish+0x2d8 sys/kern/kern_synch.c:367 rw_do_enter_write(fffffd806bbdf688,1) at rw_do_enter_write+0x1dc sys/kern/kern_rwlock.c:298 rrw_enter(fffffd806bbdf688,1) at rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 VOP_LOCK(fffffd8069b2caf8,2001) at VOP_LOCK+0xa3 sys/kern/vfs_vops.c:527 vn_lock(fffffd8069b2caf8,2001) at vn_lock+0xa4 sys/kern/vfs_vnops.c:570 vget(fffffd8069b2caf8,2001) at vget+0x2a2 sys/kern/vfs_subr.c:687 ktrwriteraw(ffff8000333e1cb8,fffffd8069b2caf8,fffffd80097fb548,ffff80003a8a1d90,ffff80003a8a1d70) at ktrwriteraw+0x175 sys/kern/kern_ktrace.c:688 ktrsysret(ffff8000333e1cb8,5b,0,ffff80003a8a1e60) at ktrsysret+0x192 ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrsysret(ffff8000333e1cb8,5b,0,ffff80003a8a1e60) at ktrsysret+0x192 sys/kern/kern_ktrace.c:209 syscall(ffff80003a8a1f10) at syscall+0xa50 mi_syscall_return sys/sys/syscall_mi.h:204 [inline] syscall(ffff80003a8a1f10) at syscall+0xa50 sys/arch/amd64/amd64/trap.c:769 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x7a6cc4fd7c70, count: -19 ddb{0}> machine ddbcpu 1 Stopped at sys_shmat+0xe0: movl $0xffffffffffffffff,0(%r14) sys_shmat(ffff8000fffee7e0,ffff80002a3ae710,ffff80002a3ae660) at sys_shmat+0xe0 sys/kern/sysv_shm.c:235 syscall(ffff80002a3ae710) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3ae710) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8127187f5d0, count: 12 ddb{1}> trace sys_shmat(ffff8000fffee7e0,ffff80002a3ae710,ffff80002a3ae660) at sys_shmat+0xe0 sys/kern/sysv_shm.c:235 syscall(ffff80002a3ae710) at syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff80002a3ae710) at syscall+0xb17 sys/arch/amd64/amd64/trap.c:748 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x8127187f5d0, count: -3