uvm_fault(0xffffffff83a1fad0, 0xffff800023c65da4, 0, 2) -> d kernel: page fault trap, code=2 Stopped at memset+0x49: repe stosb %es:(%rdi) TID PID UID PRFLAGS PFLAGS CPU COMMAND *205989 86559 0 0x2 0x1 0 syz-executor memset() at memset+0x49 ffs_write(ffff80002a858e10) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401 VOP_WRITE(fffffd806b110018,ffff80002a858ec0,3,fffffd8007ffd680) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a7462a0,fffffd806b110018,fffffd8007ffd680,ffff80002a858f90,ffff80002a858f70) at ktrwriteraw+0x19b sys/kern/kern_ktrace.c:691 ktrsysret(ffff80002a7462a0,5b,0,ffff80002a859050) at ktrsysret+0x17f ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrsysret(ffff80002a7462a0,5b,0,ffff80002a859050) at ktrsysret+0x17f sys/kern/kern_ktrace.c:209 syscall(ffff80002a859100) at syscall+0xad9 mi_syscall_return sys/sys/syscall_mi.h:204 [inline] syscall(ffff80002a859100) at syscall+0xad9 sys/arch/amd64/amd64/trap.c:804 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x716474075f80, count: 8 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> ddb> set $lines = 0 ddb> set $maxwidth = 0 ddb> show panic *cpu0: uvm_fault(0xffffffff83a1fad0, 0xffff800023c65da4, 0, 2) -> d ddb> trace memset() at memset+0x49 ffs_write(ffff80002a858e10) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401 VOP_WRITE(fffffd806b110018,ffff80002a858ec0,3,fffffd8007ffd680) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 ktrwriteraw(ffff80002a7462a0,fffffd806b110018,fffffd8007ffd680,ffff80002a858f90,ffff80002a858f70) at ktrwriteraw+0x19b sys/kern/kern_ktrace.c:691 ktrsysret(ffff80002a7462a0,5b,0,ffff80002a859050) at ktrsysret+0x17f ktrwrite2 sys/kern/kern_ktrace.c:-1 [inline] ktrsysret(ffff80002a7462a0,5b,0,ffff80002a859050) at ktrsysret+0x17f sys/kern/kern_ktrace.c:209 syscall(ffff80002a859100) at syscall+0xad9 mi_syscall_return sys/sys/syscall_mi.h:204 [inline] syscall(ffff80002a859100) at syscall+0xad9 sys/arch/amd64/amd64/trap.c:804 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0x716474075f80, count: -7 ddb> show registers rdi 0xffff800023c65da4 rsi 0 rbp 0xffff80002a858d30 rbx 0xfda4 __ALIGN_SIZE+0xeda4 rdx 0x4 rcx 0x4 rax 0 r8 0x258 r9 0xffff80002a858c90 r10 0xa11e9aa9032154e8 r11 0xffff800023c65da4 r12 0x3da4 __ALIGN_SIZE+0x2da4 r13 0x4000 __ALIGN_SIZE+0x3000 r14 0xfffffd806b110018 r15 0x1 rip 0xffffffff830c65d9 memset+0x49 cs 0x8 rflags 0x10202 __ALIGN_SIZE+0xf202 rsp 0xffff80002a858b28 ss 0x10 memset+0x49: repe stosb %es:(%rdi) ddb> show proc PROC (syz-executor) tid=205989 pid=86559 tcnt=1 stat=onproc flags process=2 proc=1 runpri=32, usrpri=81, slppri=32, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002a747230,0xffff80002a746018 process=0xffff80002a7ae410 user=0xffff80002a854000, vmspace=0xfffffd8070ce08a8 estcpu=31, cpticks=6, pctcpu=0.1, user=0, sys=6, intr=0 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 2706 161713 27589 0 2 0x10 syz-executor 2706 279033 27589 0 2 0x4000010 syz-executor 3956 374284 51096 -1 2 0x10 syz-executor 3956 42333 51096 -1 3 0x4000090 fsleep syz-executor 76307 6112 86559 0 2 0 syz-executor 76307 270095 86559 0 3 0x4000080 ttyin syz-executor 76307 89193 86559 0 2 0x4000000 syz-executor 45086 358838 21426 0 2 0x1 syz-executor 45086 166913 21426 0 3 0x4000081 fsleep syz-executor 18664 24613 1 0 3 0x80 nanoslp init 64718 387411 20415 0 3 0x80 nanoslp syz-executor 64718 30277 20415 0 3 0x4000088 kqread syz-executor 64718 501389 20415 0 3 0x4000080 sbwait syz-executor 64718 309142 20415 0 3 0x4000080 fsleep syz-executor 1917 211478 0 0 3 0x14200 acct acct 52227 209320 28404 0 3 0x80 nanoslp syz-executor 52227 217194 28404 0 3 0x4000080 kqsel syz-executor 20415 384991 95035 0 3 0x82 nanoslp syz-executor 28404 6527 95035 0 3 0x82 nanoslp syz-executor *86559 205989 95035 0 7 0x3 syz-executor 27589 97096 95035 0 3 0x82 nanoslp syz-executor 66214 20802 95035 0 2 0x2 syz-executor 51096 454163 95035 0 3 0x82 nanoslp syz-executor 21426 296427 95035 0 3 0x82 nanoslp syz-executor 95035 419822 1 0 3 0x82 wait syz-executor 28337 221512 0 0 3 0x14200 bored smr 74118 508467 0 0 2 0x14200 zerothread 76639 415856 0 0 3 0x14200 aiodoned aiodoned 26544 477489 0 0 3 0x14200 syncer update 59458 59293 0 0 3 0x14200 cleaner cleaner 35858 330221 0 0 3 0x14200 reaper reaper 2093 11815 0 0 3 0x14200 pgdaemon pagedaemon 98182 4029 0 0 3 0x14200 bored viomb 64156 22052 0 0 3 0x40014200 acpi0 acpi0 29323 51034 0 0 3 0x14200 bored softnet0 24158 337045 0 0 3 0x14200 bored systqmp 79497 163270 0 0 3 0x14200 bored systq 77488 280422 0 0 3 0x40014200 tmoslp softclock 99358 416158 0 0 3 0x40014200 idle0 1 182241 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb>