kernel: protection fault trap, code=0
Stopped at      sys_msgrcv+0x3f2:       movq    0x10(%r13),%rdi
ddb> 
ddb> set $lines = 0
ddb> set $maxwidth = 0
ddb> show panic
the kernel did not panic
ddb> trace
sys_msgrcv(ffff8000384d1ca8,ffff80002a7a5750,ffff80002a7a56a0) at sys_msgrcv+0x3f2 msg_copyout sys/kern/sysv_msg.c:639 [inline]
sys_msgrcv(ffff8000384d1ca8,ffff80002a7a5750,ffff80002a7a56a0) at sys_msgrcv+0x3f2 sys/kern/sysv_msg.c:349
syscall(ffff80002a7a5750) at syscall+0x962 mi_syscall sys/sys/syscall_mi.h:-1 [inline]
syscall(ffff80002a7a5750) at syscall+0x962 sys/arch/amd64/amd64/trap.c:783
Xsyscall() at Xsyscall+0x128
end of kernel
end trace frame: 0xef246da3680, count: -3
ddb> show registers
rdi                                0
rsi                   0x2000deafce75
rbp               0xffff80002a7a5680
rbx               0xd2188a986bec2109
rdx                                0
rcx                                0
rax               0xffff8000384d1ca8
r8                    0x7f7fffffc000
r9                                 0
r10               0xa15b05a90b767f25
r11               0xa3247ece89f7b135
r12               0xfffffd8064028d98
r13               0xd2188a986bec2109
r14               0xffff8000015a6c00
r15                   0x2000deafce75
rip               0xffffffff81d4ce42    sys_msgrcv+0x3f2
cs                               0x8
rflags                       0x10246    __ALIGN_SIZE+0xf246
rsp               0xffff80002a7a55e0
ss                              0x10
sys_msgrcv+0x3f2:       movq    0x10(%r13),%rdi
ddb>