8ÈbgxeZÍÂpanic: 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(ffffffff81837554,ffff80002115ec30,ffff80002109c270,ffff800000038e80) at __assert+0x24 sys/kern/subr_prf.c:155 _kernel_lock(ffff80002109c270,ffff80002115a000) 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,ffff80002109c270) at alltraps_kern+0x7b ptsignal(1b45,ffff80002109c270,ffff8000210cafe8) at ptsignal+0x115 sys/kern/kern_sig.c:944 mi_switch() at mi_switch+0x1fb sys/kern/sched_bsd.c:392 sleep_finish(1,ffff80002115eec0) at sleep_finish+0xd3 sys/kern/kern_synch.c:312 sleep_finish_all(ffff80002115eec0,32) at sleep_finish_all+0x22 sleep_finish_timeout sys/kern/kern_synch.c:336 [inline] sleep_finish_all(ffff80002115eec0,32) at sleep_finish_all+0x22 sys/kern/kern_synch.c:157 tsleep(ffff80002109c270,3,0,ffff8000210cb0b0) at tsleep+0x142 single_thread_set(ffff80002109c270,ffff80002109c270,0) at single_thread_set+0x28b single_thread_wait sys/kern/kern_sig.c:2051 [inline] single_thread_set(ffff80002109c270,ffff80002109c270,0) at single_thread_set+0x28b sys/kern/kern_sig.c:2042 exit1(ffff80002109c270,9,0) at exit1+0x84 sys/kern/kern_exit.c:137 end trace frame: 0xffff80002115f090, 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(ffffffff81837554,ffff80002115ec30,ffff80002109c270,ffff800000038e80) at __assert+0x24 sys/kern/subr_prf.c:155 _kernel_lock(ffff80002109c270,ffff80002115a000) 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,ffff80002109c270) at alltraps_kern+0x7b ptsignal(1b45,ffff80002109c270,ffff8000210cafe8) at ptsignal+0x115 sys/kern/kern_sig.c:944 mi_switch() at mi_switch+0x1fb sys/kern/sched_bsd.c:392 sleep_finish(1,ffff80002115eec0) at sleep_finish+0xd3 sys/kern/kern_synch.c:312 sleep_finish_all(ffff80002115eec0,32) at sleep_finish_all+0x22 sleep_finish_timeout sys/kern/kern_synch.c:336 [inline] sleep_finish_all(ffff80002115eec0,32) at sleep_finish_all+0x22 sys/kern/kern_synch.c:157 tsleep(ffff80002109c270,3,0,ffff8000210cb0b0) at tsleep+0x142 single_thread_set(ffff80002109c270,ffff80002109c270,0) at single_thread_set+0x28b single_thread_wait sys/kern/kern_sig.c:2051 [inline] single_thread_set(ffff80002109c270,ffff80002109c270,0) at single_thread_set+0x28b sys/kern/kern_sig.c:2042 exit1(ffff80002109c270,9,0) at exit1+0x84 sys/kern/kern_exit.c:137 postsig(100,ffff80002109c270) at postsig+0x3ea sigexit sys/kern/kern_sig.c:1500 [inline] postsig(100,ffff80002109c270) at postsig+0x3ea sys/kern/kern_sig.c:1432 userret(0) at userret+0x11b sys/kern/kern_sig.c:1882 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,dfc06e66a00,53,0,dfc06e62060) at Xsyscall+0x128 end of kernel end trace frame: 0xdfc05383370, count: -18 ddb{1}> show registers rdi 0xffffffff81e3e438 kprintf_mutex rsi 0xffffffff817b9589 db_enter+0x9 rbp 0xffff80002115eb90 rbx 0xffff80002115ec30 rdx 0xffff800002ad7000 rcx 0x4070 __ALIGN_SIZE+0x3070 rax 0xffff800002ad7000 r8 0xffff80002115eb60 r9 0x8080808080808080 r10 0x3697049370ce794d r11 0xffffffff81780d60 x86_bus_space_io_read_1 r12 0x3000000008 r13 0xffff80002115eba0 r14 0x100 r15 0xffffffff81bf5460 cmd0646_9_tim_udma+0x20a25 rip 0xffffffff817b958a db_enter+0xa cs 0x8 rflags 0x212 rsp 0xffff80002115eb90 ss 0x10 db_enter+0xa: popq %rbp ddb{1}> show proc PROC (syz-executor1) pid=164853 stat=sleep flags process=1000 proc=4002000 pri=50, usrpri=82, nice=20 forw=0x0, list=0xffff80002109d530,0xffff80002109dc48 process=0xffff8000210cafe8 user=0xffff80002115a000, vmspace=0xffffff007f124738 estcpu=36, cpticks=0, pctcpu=0.0 user=0, sys=0, intr=0 ddb{1}> ps PID TID PPID UID S FLAGS WAIT COMMAND 19035 254960 65409 0 3 0x80 nanosleep syz-executor0 19035 25621 65409 0 3 0x4000000 biowait syz-executor0 19035 432715 65409 0 3 0x4000080 fsleep syz-executor0 *79090 164853 98559 0 3 0x4003000 suspend syz-executor1 79090 465931 98559 0 2 0x4081080 syz-executor1 99084 318502 1 0 3 0x100083 ttyin getty 51996 245665 0 0 3 0x14200 bored sosplice 98559 228261 49746 0 3 0x82 nanosleep syz-executor1 65409 132402 49746 0 3 0x82 nanosleep syz-executor0 49746 285238 56027 0 3 0x82 thrsleep syz-fuzzer 49746 211485 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 226913 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 154448 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 174192 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 278946 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 401545 56027 0 3 0x4000082 kqread syz-fuzzer 49746 302735 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 71731 56027 0 3 0x4000082 thrsleep syz-fuzzer 49746 1933 56027 0 3 0x4000082 thrsleep syz-fuzzer 56027 188433 89079 0 3 0x10008a pause ksh 89079 139702 37534 0 3 0x92 select sshd 37534 409241 1 0 3 0x80 select sshd 27068 4397 36234 73 3 0x100090 kqread syslogd 36234 76736 1 0 3 0x100082 netio syslogd 47367 428195 1 77 3 0x100090 poll dhclient 70929 160937 1 0 3 0x80 poll dhclient 9116 243704 0 0 3 0x14200 pgzero zerothread 28801 377914 0 0 3 0x14200 aiodoned aiodoned 20573 261290 0 0 3 0x14200 syncer update 21026 259785 0 0 3 0x14200 cleaner cleaner 44778 135451 0 0 3 0x14200 reaper reaper 78955 41996 0 0 3 0x14200 pgdaemon pagedaemon 29655 50313 0 0 3 0x14200 bored crynlk 80472 119681 0 0 3 0x14200 bored crypto 16391 322262 0 0 3 0x40014200 acpi0 acpi0 34827 24218 0 0 3 0x40014200 idle1 80070 136732 0 0 3 0x14200 bored softnet 42767 14257 0 0 3 0x14200 bored systqmp 44377 436506 0 0 3 0x14200 bored systq 66873 418319 0 0 3 0x40014200 bored softclock 61403 158600 0 0 3 0x40014200 idle0 1 456574 0 0 3 0x82 wait init 0 0 -1 0 3 0x10200 scheduler swapper