some questions about SMP?

[mkfree]

You are right when writing to the device it is necessary to put volatile to prevent the compiler from optimizing this variable,
I really hadn't gotten to this part of the code, I stayed in the write part of the kernel page directory the
APIC memory. In bochs it does not continue from there, it only gives the error that I mentioned before and ends with the execution.
You have tested your implementation with the bochs?

[nexos]

Yes, I have, but you can try QEMU.

[mkfree]

I already found my error, at some point add an initialization 0 of the content of the physical pages to do some tests, it is already solved,
thanks for your time