uvm_fault(0xffffffff839ec6e0, 0xffff800026322000, 0, 2) -> d kernel: page fault trap, code=2 Stopped at memset+0x52: repe stosq %es:(%rdi) TID PID UID PRFLAGS PFLAGS CPU COMMAND *265074 59488 0 0 0x4000000 1K syz-executor memset() at memset+0x52 VOP_WRITE(fffffd806870dda0,ffff800039fcfdf8,7,fffffd80097fd4e0) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_write(fffffd806f566e68,ffff800039fcfdf8,0) at vn_write+0x1d3 sys/kern/vfs_vnops.c:408 dofilewritev(ffff80002ffa82b8,3,ffff800039fcfdf8,0,ffff800039fcfeb0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384 sys_write(ffff80002ffa82b8,ffff800039fcff60,ffff800039fcfeb0) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff800039fcff60) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800039fcff60) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xcffd118b620, 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{1}> ddb{1}> set $lines = 0 ddb{1}> set $maxwidth = 0 ddb{1}> show panic *cpu1: uvm_fault(0xffffffff839ec6e0, 0xffff800026322000, 0, 2) -> d ddb{1}> trace memset() at memset+0x52 VOP_WRITE(fffffd806870dda0,ffff800039fcfdf8,7,fffffd80097fd4e0) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_write(fffffd806f566e68,ffff800039fcfdf8,0) at vn_write+0x1d3 sys/kern/vfs_vnops.c:408 dofilewritev(ffff80002ffa82b8,3,ffff800039fcfdf8,0,ffff800039fcfeb0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384 sys_write(ffff80002ffa82b8,ffff800039fcff60,ffff800039fcfeb0) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff800039fcff60) at syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] syscall(ffff800039fcff60) at syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xcffd118b620, count: -7 ddb{1}> show registers rdi 0xffff800026322000 rsi 0 rbp 0xffff800039fcfc30 rbx 0xe rdx 0 rcx 0x800 rax 0 r8 0x4000 __ALIGN_SIZE+0x3000 r9 0x1 r10 0xb08b1094174545b r11 0xffff800026322000 r12 0x4000 __ALIGN_SIZE+0x3000 r13 0x4000 __ALIGN_SIZE+0x3000 r14 0xffff800026322000 r15 0x4000 __ALIGN_SIZE+0x3000 rip 0xffffffff82fa1452 memset+0x52 cs 0x8 rflags 0x10206 __ALIGN_SIZE+0xf206 rsp 0xffff800039fcfb68 ss 0x10 memset+0x52: repe stosq %es:(%rdi) ddb{1}> show proc PROC (syz-executor) tid=265074 pid=59488 tcnt=2 stat=onproc flags process=0 proc=4000000 runpri=17, usrpri=81, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0x0 scnt=0 ecnt=0 forw=0xffffffffffffffff, list=0xffff80002ffa8550,0xffff80002ffa94f0 process=0xffff8000fffef508 user=0xffff800039fcb000, vmspace=0xfffffd800b063000 estcpu=31, cpticks=28, pctcpu=0.23, user=0, sys=27, intr=1 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 25450 244586 87345 0 2 0x80 syz-executor 25450 218251 87345 0 3 0x4000080 fsleep syz-executor 78174 346513 85310 0 3 0x80 fsleep syz-executor 78174 393508 85310 0 3 0x4000080 kqread syz-executor 27187 46075 16590 0 3 0x80 fsleep syz-executor 27187 137980 16590 0 3 0x4000080 sbwait syz-executor 17309 297039 61307 0 3 0x80 fsleep syz-executor 17309 339922 61307 0 2 0x4000000 syz-executor 58460 74554 0 0 3 0x14200 acct acct 59488 386614 59138 0 3 0x80 fsleep syz-executor *59488 265074 59138 0 7 0x4000000 syz-executor 16590 72301 17364 0 3 0x82 nanoslp syz-executor 65207 463889 87442 0 3 0x80 fsleep syz-executor 65207 153650 87442 0 3 0x4000088 kqread syz-executor 27004 460061 66633 0 3 0x80 fsleep syz-executor 27004 319577 66633 0 3 0x4000080 bell syz-executor 35106 18513 1 0 3 0x80 nanoslp init 87345 216852 17364 0 3 0x82 nanoslp syz-executor 59138 197173 17364 0 3 0x82 nanoslp syz-executor 61307 183354 17364 0 3 0x82 nanoslp syz-executor 51593 443187 17364 0 2 0x2 syz-executor 85310 91548 17364 0 3 0x82 nanoslp syz-executor 66633 24602 17364 0 3 0x82 nanoslp syz-executor 87442 384076 17364 0 3 0x82 nanoslp syz-executor 17364 314179 1 0 3 0x82 kqread syz-executor 74379 435227 0 0 3 0x14200 bored smr 75984 239543 0 0 3 0x14200 pgzero zerothread 10285 395896 0 0 3 0x14200 aiodoned aiodoned 87414 261812 0 0 3 0x14200 syncer update 75787 113299 0 0 3 0x14200 cleaner cleaner 36289 96382 0 0 3 0x14200 reaper reaper 23104 242419 0 0 3 0x14200 pgdaemon pagedaemon 2734 406946 0 0 3 0x14200 bored viomb 53710 442045 0 0 3 0x40014200 acpi0 acpi0 49732 3344 0 0 3 0x40014200 idle1 95113 37857 0 0 3 0x14200 bored softnet1 22878 317688 0 0 3 0x14200 bored softnet0 40472 133112 0 0 3 0x14200 bored systqmp 49786 106282 0 0 3 0x14200 bored systq 39213 35224 0 0 3 0x14200 tmoslp softclockmp 36506 127326 0 0 3 0x40014200 tmoslp softclock 38994 372659 0 0 7 0x40014200 idle0 1 54837 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb{1}> show all locks Process 17309 (syz-executor) thread 0xffff80002a241770 (339922) exclusive rrwlock inode r = 0 (0xfffffd806bef3440) #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 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x18f sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x2bd sys/kern/sys_generic.c:384 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #9 Xsyscall+0x128 Process 59488 (syz-executor) thread 0xffff80002ffa82b8 (265074) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff83a1dd40) #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 sleep_finish+0x2d8 sys/kern/kern_synch.c:369 #3 biowait+0xc6 sys/kern/vfs_bio.c:1242 #4 bwrite+0x2e7 sys/kern/vfs_bio.c:754 #5 ffs2_balloc+0x18b4 sys/ufs/ffs/ffs_balloc.c:701 #6 ffs_write+0x4f9 sys/ufs/ffs/ffs_vnops.c:345 #7 VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 #8 vn_write+0x1d3 sys/kern/vfs_vnops.c:408 #9 dofilewritev+0x2bd sys/kern/sys_generic.c:384 #10 sys_write+0xa2 sys/kern/sys_generic.c:300 #11 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #11 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #12 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806f09da58) #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 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 vn_lock+0xa4 sys/kern/vfs_vnops.c:570 #5 vn_write+0x18f sys/kern/vfs_vnops.c:405 #6 dofilewritev+0x2bd sys/kern/sys_generic.c:384 #7 sys_write+0xa2 sys/kern/sys_generic.c:300 #8 syscall+0xbd4 mi_syscall sys/sys/syscall_mi.h:176 [inline] #8 syscall+0xbd4 sys/arch/amd64/amd64/trap.c:783 #9 Xsyscall+0x128 Process 51593 (syz-executor) thread 0xffff80002a241ca0 (443187) exclusive rrwlock inode r = 0 (0xfffffd806f73ac98) #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 rrw_enter+0xc6 sys/kern/kern_rwlock.c:621 #3 VOP_LOCK+0xbd sys/kern/vfs_vops.c:527 #4 ufs_ihashins+0x4f ufs_ihash sys/ufs/ufs/ufs_ihash.c:-1 [inline] #4 ufs_ihashins+0x4f sys/ufs/ufs/ufs_ihash.c:159 #5 ffs_vget+0x187 sys/ufs/ffs/ffs_vfsops.c:1232 #6 ffs_inode_alloc+0x279 sys/ufs/ffs/ffs_alloc.c:393 #7 ufs_mkdir+0xfc sys/ufs/ufs/ufs_vnops.c:1112 #8 VOP_MKDIR+0x101 sys/kern/vfs_vops.c:394 #9 domkdirat+0x179 sys/kern/vfs_syscalls.c:3143 #10 syscall+0xb17 mi_syscall sys/sys/syscall_mi.h:176 [inline] #10 syscall+0xb17 sys/arch/amd64/amd64/trap.c:783 #11 Xsyscall+0x128 exclusive rrwlock inode r = 0 (0xfffffd806cf70680) #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+0x41 rw_self sys/kern/kern_rwlock.c:84 [inline] #1 rw_do_enter_write+0x41 sys/kern/kern_rwlock.c:223