login: panic: kernel diagnostic assertion "__mp_lock_held(&sched_lock, curcpu()) == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_lock.c", line 63 Stopped at db_enter+0xa: popq %rbp TID PID UID PRFLAGS PFLAGS CPU COMMAND db_enter() at db_enter+0xa sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x147 sys/kern/subr_prf.c:208 __assert(ffffffff811f60a4,ffff8000211a50c0,ffff8000210cabd0,ffff800000038e80) at __assert+0x24 sys/kern/subr_prf.c:155 _kernel_lock(ffff8000210cabd0,ffff8000211a0000) at _kernel_lock+0x125 sys/kern/kern_lock.c:63 pageflttrap() at pageflttrap+0x6c sys/arch/amd64/amd64/trap.c:163 kerntrap(9) at kerntrap+0x8d sys/arch/amd64/amd64/trap.c:294 alltraps_kern(6,ffff800002ad7000,ffffffffffffffff,0,9,ffff8000210cabd0) at alltraps_kern+0x7b ptsignal(1915,ffff8000210cabd0,ffff8000210a3968) at ptsignal+0x115 sys/kern/kern_sig.c:932 mi_switch() at mi_switch+0x1fb sys/kern/sched_bsd.c:392 sleep_finish(1,ffff8000211a5350) at sleep_finish+0xd3 sys/kern/kern_synch.c:312 sleep_finish_all(ffff8000211a5350,32) at sleep_finish_all+0x22 sleep_finish_timeout sys/kern/kern_synch.c:336 [inline] sleep_finish_all(ffff8000211a5350,32) at sleep_finish_all+0x22 sys/kern/kern_synch.c:157 tsleep(ffff8000210cabd0,3,0,ffff8000210a3a30) at tsleep+0x142 single_thread_set(ffff8000210cabd0,ffff8000210cabd0,0) at single_thread_set+0x28b single_thread_wait sys/kern/kern_sig.c:2039 [inline] single_thread_set(ffff8000210cabd0,ffff8000210cabd0,0) at single_thread_set+0x28b sys/kern/kern_sig.c:2030 exit1(ffff8000210cabd0,9,0) at exit1+0x84 sys/kern/kern_exit.c:137 end trace frame: 0xffff8000211a5520, 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{1}> ddb{1}> set $lines = 0 ddb{1}> show panic kernel diagnostic assertion "__mp_lock_held(&sched_lock, curcpu()) == 0" failed: file "/syzkaller/managers/multicore/kernel/sys/kern/kern_lock.c", line 63 ddb{1}> trace db_enter() at db_enter+0xa sys/arch/amd64/amd64/db_interface.c:399 panic() at panic+0x147 sys/kern/subr_prf.c:208 __assert(ffffffff811f60a4,ffff8000211a50c0,ffff8000210cabd0,ffff800000038e80) at __assert+0x24 sys/kern/subr_prf.c:155 _kernel_lock(ffff8000210cabd0,ffff8000211a0000) at _kernel_lock+0x125 sys/kern/kern_lock.c:63 pageflttrap() at pageflttrap+0x6c sys/arch/amd64/amd64/trap.c:163 kerntrap(9) at kerntrap+0x8d sys/arch/amd64/amd64/trap.c:294 alltraps_kern(6,ffff800002ad7000,ffffffffffffffff,0,9,ffff8000210cabd0) at alltraps_kern+0x7b ptsignal(1915,ffff8000210cabd0,ffff8000210a3968) at ptsignal+0x115 sys/kern/kern_sig.c:932 mi_switch() at mi_switch+0x1fb sys/kern/sched_bsd.c:392 sleep_finish(1,ffff8000211a5350) at sleep_finish+0xd3 sys/kern/kern_synch.c:312 sleep_finish_all(ffff8000211a5350,32) at sleep_finish_all+0x22 sleep_finish_timeout sys/kern/kern_synch.c:336 [inline] sleep_finish_all(ffff8000211a5350,32) at sleep_finish_all+0x22 sys/kern/kern_synch.c:157 tsleep(ffff8000210cabd0,3,0,ffff8000210a3a30) at tsleep+0x142 single_thread_set(ffff8000210cabd0,ffff8000210cabd0,0) at single_thread_set+0x28b single_thread_wait sys/kern/kern_sig.c:2039 [inline] single_thread_set(ffff8000210cabd0,ffff8000210cabd0,0) at single_thread_set+0x28b sys/kern/kern_sig.c:2030 exit1(ffff8000210cabd0,9,0) at exit1+0x84 sys/kern/kern_exit.c:137 postsig(100,ffff8000210cabd0) at postsig+0x3ea sigexit sys/kern/kern_sig.c:1488 [inline] postsig(100,ffff8000210cabd0) at postsig+0x3ea sys/kern/kern_sig.c:1420 userret(0) at userret+0x11b sys/kern/kern_sig.c:1870 syscall(0) at syscall+0x54d mi_syscall_return sys/sys/syscall_mi.h:122 [inline] syscall(0) at syscall+0x54d sys/arch/amd64/amd64/trap.c:605 Xsyscall(6,58,4303d86d400,53,0,430b98c2520) at Xsyscall+0x128 end of kernel end trace frame: 0x43053d58260, count: -18 ddb{1}> show registers rdi 0xffffffff81e25b10 kprintf_mutex rsi 0xffffffff81b50ed9 db_enter+0x9 rbp 0xffff8000211a5020 rbx 0xffff8000211a50c0 rdx 0xffff800002ad7000 rcx 0x43d6 __ALIGN_SIZE+0x33d6 rax 0xffff800002ad7000 r8 0xffff8000211a4ff0 r9 0x8080808080808080 r10 0xc7c65a73a8c5a8f8 r11 0xffffffff819ddb60 x86_bus_space_io_read_1 r12 0x3000000008 r13 0xffff8000211a5030 r14 0x100 r15 0xffffffff81bf34c3 cmd0646_9_tim_udma+0x1f76b rip 0xffffffff81b50eda db_enter+0xa cs 0x8 rflags 0x202 rsp 0xffff8000211a5020 ss 0x10 db_enter+0xa: popq %rbp ddb{1}> show proc PROC (syz-executor1) pid=105588 stat=sleep flags process=1000 proc=4002000 pri=50, usrpri=81, nice=20 forw=0x0, list=0xffff8000210ca720,0xffff8000210cb9f0 process=0xffff8000210a3968 user=0xffff8000211a0000, vmspace=0xffffff007f125e70 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 71656 414980 74481 60929 3 0x90 nanosleep syz-executor0 71656 338825 74481 60929 3 0x4000090 fsleep syz-executor0 71656 412715 74481 60929 3 0x4000090 fsleep syz-executor0 *86976 105588 27439 0 3 0x4003000 suspend syz-executor1 86976 108355 27439 0 2 0x4081080 syz-executor1 18439 361178 1 0 3 0x100083 ttyin getty 34460 366021 0 0 3 0x14200 bored sosplice 27439 506497 14842 0 3 0x82 nanosleep syz-executor1 74481 441349 14842 0 3 0x82 nanosleep syz-executor0 14842 435366 61508 0 3 0x82 kqread syz-fuzzer 14842 115080 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 14005 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 208908 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 438764 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 16631 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 423986 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 379400 61508 0 3 0x4000082 thrsleep syz-fuzzer 14842 295186 61508 0 3 0x4000082 thrsleep syz-fuzzer 61508 234336 41701 0 3 0x10008a pause ksh 41701 344488 69819 0 3 0x92 select sshd 69819 81627 1 0 3 0x80 select sshd 2837 461748 6834 73 3 0x100090 kqread syslogd 6834 101636 1 0 3 0x100082 netio syslogd 42421 17299 1 77 3 0x100090 poll dhclient 33579 19198 1 0 3 0x80 poll dhclient 32540 235793 0 0 3 0x14200 pgzero zerothread 83339 234849 0 0 3 0x14200 aiodoned aiodoned 76318 456477 0 0 3 0x14200 syncer update 70321 303515 0 0 3 0x14200 cleaner cleaner 15499 37134 0 0 3 0x14200 reaper reaper 63434 97312 0 0 3 0x14200 pgdaemon pagedaemon 4815 138142 0 0 3 0x14200 bored crynlk 14883 209758 0 0 3 0x14200 bored crypto 79477 288382 0 0 3 0x40014200 acpi0 acpi0 44185 30643 0 0 3 0x40014200 idle1 53114 465340 0 0 3 0x14200 bored softnet 88484 387955 0 0 3 0x14200 bored systqmp 19098 188256 0 0 3 0x14200 bored systq 780 351013 0 0 3 0x40014200 bored softclock 17736 213933 0 0 3 0x40014200 idle0 1 166774 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper