When I use the seabios as the payload, I got a strange issue.
 
In the seabios flow:
Post->timer_setup->rtc_updating->inb_cmos function
 
when run the inb_cmos, it will reboot on the inb operation.
 
inb_cmos disassemables to fllowing:
out 0x70, value
in value, 0x71.   ----> run here to make the reboot happen.
 
0x70 is the CMOS index port, 0x71 is the CMOS data port.
 
I suspect the "in value, 0x71" operation causes a exception and the seabios doesn't have real IDT, so it then make the reboot.
but why it cause the exception is a question for me?
since IO port 0x70 also reponsible for the NMI enble/disable, is it caused the error?
 
any one has some comments?
 
thanks

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