panic: kernel diagnostic assertion "__mp_lock_held(&sched_lock, curcpu()) == 0" failed: file "/syzkaller/managers/setuid/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(ffffffff813b6fb4,ffff8000211db9a0,ffff8000210a3080,ffff800000038e80) at __assert+0x24 sys/kern/subr_prf.c:155
_kernel_lock(ffff8000210a3080,ffff8000211d6000) 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,ffff800000ed7000,ffffffffffffffff,0,9,ffff8000210a3080) at alltraps_kern+0x7b
ptsignal(5f22,ffff8000210a3080,ffff8000210b6cb8) at ptsignal+0x115 sys/kern/kern_sig.c:932
mi_switch() at mi_switch+0x1fb sys/kern/sched_bsd.c:392
sleep_finish(1,ffff8000211dbc30) at sleep_finish+0xd3 sys/kern/kern_synch.c:312
sleep_finish_all(ffff8000211dbc30,32) at sleep_finish_all+0x22 sleep_finish_timeout sys/kern/kern_synch.c:336 [inline]
sleep_finish_all(ffff8000211dbc30,32) at sleep_finish_all+0x22 sys/kern/kern_synch.c:157
tsleep(ffff8000210a3080,3,0,ffff8000210b6d80) at tsleep+0x142
single_thread_set(ffff8000210a3080,ffff8000210a3080,0) at single_thread_set+0x28b single_thread_wait sys/kern/kern_sig.c:2039 [inline]
single_thread_set(ffff8000210a3080,ffff8000210a3080,0) at single_thread_set+0x28b sys/kern/kern_sig.c:2030
exit1(ffff8000210a3080,9,0) at exit1+0x84 sys/kern/kern_exit.c:137
end trace frame: 0xffff8000211dbe00, count: 0
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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/setuid/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(ffffffff813b6fb4,ffff8000211db9a0,ffff8000210a3080,ffff800000038e80) at __assert+0x24 sys/kern/subr_prf.c:155
_kernel_lock(ffff8000210a3080,ffff8000211d6000) 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,ffff800000ed7000,ffffffffffffffff,0,9,ffff8000210a3080) at alltraps_kern+0x7b
ptsignal(5f22,ffff8000210a3080,ffff8000210b6cb8) at ptsignal+0x115 sys/kern/kern_sig.c:932
mi_switch() at mi_switch+0x1fb sys/kern/sched_bsd.c:392
sleep_finish(1,ffff8000211dbc30) at sleep_finish+0xd3 sys/kern/kern_synch.c:312
sleep_finish_all(ffff8000211dbc30,32) at sleep_finish_all+0x22 sleep_finish_timeout sys/kern/kern_synch.c:336 [inline]
sleep_finish_all(ffff8000211dbc30,32) at sleep_finish_all+0x22 sys/kern/kern_synch.c:157
tsleep(ffff8000210a3080,3,0,ffff8000210b6d80) at tsleep+0x142
single_thread_set(ffff8000210a3080,ffff8000210a3080,0) at single_thread_set+0x28b single_thread_wait sys/kern/kern_sig.c:2039 [inline]
single_thread_set(ffff8000210a3080,ffff8000210a3080,0) at single_thread_set+0x28b sys/kern/kern_sig.c:2030
exit1(ffff8000210a3080,9,0) at exit1+0x84 sys/kern/kern_exit.c:137
postsig(100,ffff8000210a3080) at postsig+0x3ea sigexit sys/kern/kern_sig.c:1488 [inline]
postsig(100,ffff8000210a3080) 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(6,58,54fb6086800,53,0,54fcead0200) at Xsyscall+0x128
end of kernel
end trace frame: 0x55077793fb0, count: -18
ddb{1}> show registers
rdi               0xffffffff81e27fd8    kprintf_mutex
rsi               0xffffffff8180d0c9    db_enter+0x9
rbp               0xffff8000211db900
rbx               0xffff8000211db9a0
rdx               0xffff800000ed7000
rcx                           0x3f60    __ALIGN_SIZE+0x2f60
rax               0xffff800000ed7000
r8                0xffff8000211db8d0
r9                0x8080808080808080
r10               0xa8f0b96cde237d12
r11               0xffffffff812b1590    x86_bus_space_io_read_1
r12                     0x3000000008
r13               0xffff8000211db910
r14                            0x100
r15               0xffffffff81bf6fef    cmd0646_9_tim_udma+0x1ccc6
rip               0xffffffff8180d0ca    db_enter+0xa
cs                               0x8
rflags                         0x216
rsp               0xffff8000211db900
ss                              0x10
db_enter+0xa:   popq    %rbp
ddb{1}>