login: witness: thread 0xffff800020b92bd0 exiting with the following locks held: exclusive rrwlock inode r = 0 (0xfffffd806d4182c8) locked @ /syzkaller/managers/setuid/kernel/sys/ufs/ufs/ufs_vnops.c:1547 panic: thread 0xffff800020b92bd0 cannot exit while holding sleeplocks Stopped at db_enter+0x18: addq $0x8,%rsp TID PID UID PRFLAGS PFLAGS CPU COMMAND 333022 3318 0 0x2 0x480 1 syz-executor1 *484807 30779 0 0x14000 0x200 0 reaper db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x16c sys/kern/subr_prf.c:208 witness_thread_exit(1ff93726f03ccece) at witness_thread_exit+0x244 sys/kern/subr_witness.c:1377 reaper(0) at reaper+0x14f sys/kern/kern_exit.c:412 end trace frame: 0x0, count: 11 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{0}> ddb{0}> set $lines = 0 ddb{0}> show panic thread 0xffff800020b92bd0 cannot exit while holding sleeplocks ddb{0}> trace db_enter() at db_enter+0x18 sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x16c sys/kern/subr_prf.c:208 witness_thread_exit(1ff93726f03ccece) at witness_thread_exit+0x244 sys/kern/subr_witness.c:1377 reaper(0) at reaper+0x14f sys/kern/kern_exit.c:412 end trace frame: 0x0, count: -4 ddb{0}> show registers rdi 0 rsi 0x1 rbp 0xffff800020b66fc0 rbx 0xffff800020b67060 rdx 0xffffffff81ec9049 cmd0646_9_tim_udma+0x1780c rcx 0x201 rax 0x1 r8 0xffffffff816aa1c4 kprintf+0x174 r9 0x1 r10 0x21b3e9815b17a6dd r11 0x7b30f7d1b8340447 r12 0x3000000008 r13 0xffff800020b66fd0 r14 0x100 r15 0x1 rip 0xffffffff8156b348 db_enter+0x18 cs 0x8 rflags 0x246 rsp 0xffff800020b66fb0 ss 0x10 db_enter+0x18: addq $0x8,%rsp ddb{0}> show proc PROC (reaper) pid=484807 stat=onproc flags process=14000 proc=200 pri=4, usrpri=51, nice=20 forw=0xffffffffffffffff, list=0xffff800020b21068,0xffff800020b21c30 process=0xffff800020b5b3b8 user=0xffff800020b62000, vmspace=0xffffffff822fcba8 estcpu=1, cpticks=2, pctcpu=0.4 user=0, sys=2, intr=0 ddb{0}> ps PID TID PPID UID S FLAGS WAIT COMMAND 49671 174863 4877 0 2 0 syz-executor0 49671 166090 4877 0 3 0x4000080 ttyout syz-executor0 49671 44921 4877 0 3 0x4000080 ttyout syz-executor0 49671 72754 4877 0 3 0x4000080 fsleep syz-executor0 49671 171421 4877 0 2 0x4000000 syz-executor0 20792 117427 3318 0 3 0x3000 suspend syz-executor1 20792 471449 3318 0 3 0x4081000 inode syz-executor1 3318 333022 86051 0 7 0x482 syz-executor1 4877 493323 86051 0 2 0x482 syz-executor0 86051 437522 45588 0 3 0x82 thrsleep syz-execprog 86051 490166 45588 0 3 0x4000082 thrsleep syz-execprog 86051 461727 45588 0 3 0x4000082 thrsleep syz-execprog 86051 129796 45588 0 3 0x4000082 thrsleep syz-execprog 86051 35295 45588 0 3 0x4000082 thrsleep syz-execprog 86051 441405 45588 0 3 0x4000082 thrsleep syz-execprog 86051 21482 45588 0 3 0x4000082 thrsleep syz-execprog 86051 119855 45588 0 3 0x4000082 kqread syz-execprog 86051 283357 45588 0 3 0x4000082 thrsleep syz-execprog 45588 126181 18978 0 3 0x10008a pause ksh 18978 231995 22677 0 3 0x92 select sshd 8716 409330 1 0 3 0x100083 ttyin getty 22677 121164 1 0 3 0x80 select sshd 81639 16610 70821 73 2 0x100010 syslogd 70821 156111 1 0 3 0x100082 netio syslogd 23448 206415 1 77 3 0x100090 poll dhclient 11985 501700 1 0 3 0x80 poll dhclient 33660 369013 0 0 3 0x14200 pgzero zerothread 48750 144598 0 0 3 0x14200 aiodoned aiodoned 59506 303408 0 0 3 0x14200 syncer update 91133 58242 0 0 3 0x14200 cleaner cleaner *30779 484807 0 0 7 0x14200 reaper 16568 509882 0 0 3 0x14200 pgdaemon pagedaemon 38747 464190 0 0 3 0x14200 bored crynlk 45659 381787 0 0 3 0x14200 bored crypto 44574 111639 0 0 3 0x40014200 acpi0 acpi0 79298 170454 0 0 3 0x40014200 idle1 69787 483523 0 0 3 0x14200 bored softnet 81224 118676 0 0 3 0x14200 bored systqmp 72516 69806 0 0 3 0x14200 bored systq 38483 152585 0 0 2 0x40014200 softclock 41981 425814 0 0 3 0x40014200 idle0 1 408727 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper ddb{0}> show all locks Process 81639 (syslogd) thread 0xffff800020be5c30 (16610) exclusive kernel_lock &kernel_lock r = 0 (0xffffffff823260a0) locked @ /syzkaller/managers/setuid/kernel/sys/kern/sched_bsd.c:436 ddb{0}>