uvm_fault(0xffffffff8396e8e0, 0xffff800029ef6000, 0, 2) -> e kernel: page fault trap, code=2 Stopped at kcov_remote_enter+0x122: movq $0,0(%rcx) TID PID UID PRFLAGS PFLAGS CPU COMMAND *150287 77113 0 0x1000 0x4080000 0 syz-executor kcov_remote_enter(0,ffff80002a7aed10) at kcov_remote_enter+0x122 sys/dev/kcov.c:670 timeout_run(ffffffff838befe0,ffff80002a7465d0) at timeout_run+0xdf sys/kern/kern_timeout.c:696 softclock_process_tick_timeout(ffff80002a7465d0,0) at softclock_process_tick_timeout+0x230 sys/kern/kern_timeout.c:756 softclock(0) at softclock+0x152 sys/kern/kern_timeout.c:788 softintr_dispatch(0) at softintr_dispatch+0xf9 sys/kern/kern_softintr.c:87 dosoftint(0) at dosoftint+0x48 sys/arch/amd64/amd64/intr.c:862 Xsoftclock() at Xsoftclock+0x27 vinvalbuf(fffffd80677ca2c8,2,fffffd8007ffd888,ffff80003a4e42c0,0,ffffffffffffffff) at vinvalbuf+0x608 sys/kern/vfs_subr.c:2010 ffs_truncate(fffffd806c1d5b00,0,4,fffffd8007ffd888) at ffs_truncate+0xf41 sys/ufs/ffs/ffs_inode.c:-1 ffs_write(ffff80003ad03370) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401 VOP_WRITE(fffffd80677ca2c8,ffff80003ad03528,7,fffffd8007ffd888) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_write(fffffd806c42cc40,ffff80003ad03528,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408 dofilewritev(ffff80003a4e42c0,3,ffff80003ad03528,0,ffff80003ad035d0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384 sys_write(ffff80003a4e42c0,ffff80003ad03680,ffff80003ad035d0) at sys_write+0xa2 sys/kern/sys_generic.c:300 end trace frame: 0xffff80003ad03670, count: 0 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(0xffffffff8396e8e0, 0xffff800029ef6000, 0, 2) -> e ddb> trace kcov_remote_enter(0,ffff80002a7aed10) at kcov_remote_enter+0x122 sys/dev/kcov.c:670 timeout_run(ffffffff838befe0,ffff80002a7465d0) at timeout_run+0xdf sys/kern/kern_timeout.c:696 softclock_process_tick_timeout(ffff80002a7465d0,0) at softclock_process_tick_timeout+0x230 sys/kern/kern_timeout.c:756 softclock(0) at softclock+0x152 sys/kern/kern_timeout.c:788 softintr_dispatch(0) at softintr_dispatch+0xf9 sys/kern/kern_softintr.c:87 dosoftint(0) at dosoftint+0x48 sys/arch/amd64/amd64/intr.c:862 Xsoftclock() at Xsoftclock+0x27 vinvalbuf(fffffd80677ca2c8,2,fffffd8007ffd888,ffff80003a4e42c0,0,ffffffffffffffff) at vinvalbuf+0x608 sys/kern/vfs_subr.c:2010 ffs_truncate(fffffd806c1d5b00,0,4,fffffd8007ffd888) at ffs_truncate+0xf41 sys/ufs/ffs/ffs_inode.c:-1 ffs_write(ffff80003ad03370) at ffs_write+0xb9a sys/ufs/ffs/ffs_vnops.c:401 VOP_WRITE(fffffd80677ca2c8,ffff80003ad03528,7,fffffd8007ffd888) at VOP_WRITE+0x101 sys/kern/vfs_vops.c:245 vn_write(fffffd806c42cc40,ffff80003ad03528,0) at vn_write+0x1c2 sys/kern/vfs_vnops.c:408 dofilewritev(ffff80003a4e42c0,3,ffff80003ad03528,0,ffff80003ad035d0) at dofilewritev+0x2bd sys/kern/sys_generic.c:384 sys_write(ffff80003a4e42c0,ffff80003ad03680,ffff80003ad035d0) at sys_write+0xa2 sys/kern/sys_generic.c:300 syscall(ffff80003ad03680) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline] syscall(ffff80003ad03680) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783 Xsyscall() at Xsyscall+0x128 end of kernel end trace frame: 0xe783a7fdf80, count: -16 ddb> show registers rdi 0xffffffff rsi 0xffff800000c16c00 rbp 0xffff80003ad02df0 rbx 0xffff80002a7aed10 rdx 0xffff80003a4e42c0 rcx 0xffff800029ef6000 rax 0xfffffd806ccf4d20 r8 0 r9 0xffffffffffffffff r10 0x94d930261c4114b0 r11 0x46fa52218be0f34c r12 0xffffffff83260be0 endtsleep r13 0xffff80002a746538 r14 0xffff80002a7aed10 r15 0 rip 0xffffffff82b7dae2 kcov_remote_enter+0x122 cs 0x8 rflags 0x10297 __ALIGN_SIZE+0xf297 rsp 0xffff80003ad02dd0 ss 0x10 kcov_remote_enter+0x122: movq $0,0(%rcx) ddb> show proc PROC (syz-executor) tid=150287 pid=77113 tcnt=5 stat=onproc flags process=1000 proc=4080000 runpri=74, usrpri=74, slppri=17, nice=20 wchan=0x0, wmesg=, ps_single=0xffff80003a4e4fb8 scnt=4 ecnt=0 forw=0xffffffffffffffff, list=0xffff80003a4e4fb8,0xffff80002a78da18 process=0xffff8000ffffb198 user=0xffff80003acfe000, vmspace=0xfffffd806cce65d0 estcpu=24, cpticks=9, pctcpu=0.4, user=0, sys=8, intr=1 ddb> ps PID TID PPID UID S FLAGS WAIT COMMAND 68857 98893 32977 0 2 0 syz-executor 68857 489115 32977 0 3 0x4000080 fsleep syz-executor 61350 443714 83760 -1 2 0x10 syz-executor 61350 293898 83760 -1 3 0x4000090 fsleep syz-executor 61350 523357 83760 -1 3 0x4000090 fsleep syz-executor 61350 262566 83760 -1 2 0x4000010 syz-executor 7616 419882 68669 0 2 0 syz-executor 7616 260673 68669 0 3 0x4000080 fsleep syz-executor 7616 298178 68669 0 3 0x4000080 fsleep syz-executor 22069 425641 31975 0 2 0 syz-executor 22069 319476 31975 0 3 0x4000080 fifow syz-executor 78265 359270 71870 0 2 0x1 syz-executor 78265 450862 71870 0 3 0x4000080 fsleep syz-executor 63744 445301 17207 0 2 0x1 syz-executor 63744 271909 17207 0 3 0x4000080 fsleep syz-executor 87564 305804 56285 0 2 0x1 syz-executor 87564 291481 56285 0 3 0x4000080 fsleep syz-executor 48660 274524 1 0 3 0x100083 ttyin getty 77113 463301 3927 0 3 0x3000 suspend syz-executor *77113 150287 3927 0 7 0x4081000 syz-executor 77113 208204 3927 0 3 0x4081000 inode syz-executor 77113 402550 3927 0 3 0x4081000 inode syz-executor 77113 287781 3927 0 3 0x4081000 inode syz-executor 55849 309328 0 0 3 0x14200 acct acct 31975 206991 62540 0 3 0x82 nanoslp syz-executor 71870 274810 62540 0 3 0x82 nanoslp syz-executor 32977 194588 62540 0 3 0x82 nanoslp syz-executor 68669 356450 62540 0 3 0x82 nanoslp syz-executor 3927 73691 62540 0 3 0x82 wait syz-executor 56285 500865 62540 0 3 0x82 nanoslp syz-executor 17207 505053 62540 0 2 0x3 syz-executor 83760 212741 62540 0 3 0x82 nanoslp syz-executor 62540 59013 1 0 3 0x82 kqread syz-executor 19080 386449 1 73 3 0x1100090 kqread syslogd 61274 19693 0 0 3 0x14200 bored smr 10247 386096 0 0 2 0x14200 zerothread 27803 488591 0 0 3 0x14200 aiodoned aiodoned 82507 464920 0 0 3 0x14200 syncer update 20704 95472 0 0 3 0x14200 cleaner cleaner 29971 392838 0 0 3 0x14200 reaper reaper 95105 467577 0 0 3 0x14200 pgdaemon pagedaemon 23006 418233 0 0 3 0x14200 bored viomb 96706 498095 0 0 3 0x40014200 acpi0 acpi0 32820 262547 0 0 3 0x14200 bored softnet0 43952 451801 0 0 3 0x14200 bored systqmp 97499 209369 0 0 3 0x14200 bored systq 52298 408648 0 0 3 0x40014200 tmoslp softclock 5540 192145 0 0 3 0x40014200 idle0 1 456675 0 0 3 0x82 wait init 0 0 -1 0 3 0x10010200 scheduler swapper ddb> show all locks No such command ddb> show malloc Type InUse MemUse HighUse Limit Requests Type Lim devbuf 11039 12160K 12390K 166960K 12876 0 pcb 19 15K 16K 166960K 215 0 rtable 196 14K 15K 166960K 450 0 pf 30 12K 92K 166960K 150 0 ifaddr 33 5K 7K 166960K 62 0 ifgroup 47 1K 2K 166960K 88 0 sysctl 3 1K 9K 166960K 9 0 counters 33 17K 18K 166960K 51 0 ioctlops 0 0K 4K 166960K 364 0 iov 0 0K 12K 166960K 86 0 mount 1 1K 1K 166960K 1 0 log 0 0K 0K 166960K 4 0 vnodes 1389 87K 88K 166960K 1985 0 UFS quota 1 32K 32K 166960K 1 0 UFS mount 5 36K 36K 166960K 5 0 shm 2 1K 5K 166960K 12 0 VM map 2 1K 1K 166960K 2 0 sem 12 0K 1K 166960K 33 0 dirhash 12 2K 2K 166960K 36 0 ACPI 1692 195K 286K 166960K 12470 0 file desc 18 65K 97K 166960K 732 0 sigio 0 0K 0K 166960K 38 0 proc 20 25K 124K 166960K 599 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 108 0 in_multi 66 4K 7K 166960K 114 0 ether_multi 1 0K 0K 166960K 3 0 mrt 0 0K 0K 166960K 16 0 ISOFS mount 1 32K 32K 166960K 1 0 MSDOSFS mount 1 16K 16K 166960K 1 0 ttys 85 387K 387K 166960K 85 0 exec 0 0K 1K 166960K 428 0 fusefs mount 1 32K 32K 166960K 1 0 pfkey data 0 0K 0K 166960K 3 0 tdb 3 0K 0K 166960K 3 0 VM swap 8 62K 64K 166960K 10 0 UVM amap 171 84K 171K 166960K 8438 0 UVM aobj 17 5K 5K 166960K 19 0 pinsyscall 22 44K 96K 166960K 1855 0