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How much of my kernel does grub load into memory?? I am working with a grub_image.img file that is 1.44 mb so I can use it with a floppy, but how much of this is loaded into memory? Even using Grub, is it neccessary to load your OS into memory or does grub handle all this??

Currently I've put no thought into this as it is all just working and I have multithreading going etc..

Thanks

I am not sure I understand your question...?

GRUB is about loading a kernel binary. Your grub_image.img is probably a floppy image - I guess you have it read in by Bochs? In that case, your kernel binary is probably much smaller than that anyway...

It's pretty confusing. It's probably best if you post your GRUB configuration file, and probably your Makefile too so we can figure out what's going on...

Even using Grub, is it neccessary to load your OS into memory or does grub handle all this??

Again, I'm not sure what you mean. GRUB loads your kernel, and optionally, additional modules if you tell it to do so. Beyond that, everything else has to be handled by you (i.e., your kernel).

I think you've answered my question then. If grub loads the kernel from my image file then I'm assuming, no matter how large the kernel is it will be loaded into memory at the starting location I assign (i.e. 0x100000).

GRUB will boot whatever bytes it will find in the kernel= file on the root= device. It will also load whatever module= file you tell him. It's unlikely to read more than 1.44MB on a floppy disk, of course.