Ok, I'm new here, but I did search thoroughly for anything related to my problem, not only here but everywhere I cound find related to the subject of operating system development. I've been trying to figure this one out for a few days now, and I've come to a dead end.
I'm setting up my memory manager for my kernel, and I have my GDT setup, and I was able to enable the first 4MB of memory in paging. I'm trying to extend this, but it's not working. Here's exactly what I've tracked it down to.
When I write the page table entry for a page of memory, nothing is actually written. I can read it back on the next line of code, and it's 0x00000000. I've verified the value that's being used to write it, and it's correct. I can't for the life of me figure out WHY it won't maintain the memory I'm writing. I haven't even added this set of pages to the directory yet.
Anyone have any suggestions? As I said, I've exhausted all my ideas. I'd just like to get this working so I can continue development on other aspects of the kernel.
Paging Memory problems
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Adek336
Re:Paging Memory problems
Welcome to MT 
This seems familiar. I remember I used to write memory and then reread however the value never changed.. if I only remembered what was the problem
One thing which comes to mind.. the page table isn't placed into the 0xa0000-0x100000 area? Prob'bly not..
Don't be shy, post some code
Cheers,
Adrian.
This seems familiar. I remember I used to write memory and then reread however the value never changed.. if I only remembered what was the problem
One thing which comes to mind.. the page table isn't placed into the 0xa0000-0x100000 area? Prob'bly not..
Don't be shy, post some code
Cheers,
Adrian.
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Sardak
Re:Paging Memory problems
That was exactly it. Thank you!
I had my page tables rooted at 0x9c000 (that was the example address given in a document I was referencing, and I never bothered to change it.) Once it got a few tables in, it overflowed into the 0xa0000 region. I never noticed anything, because I'm not using a graphics mode, yet. Just updated my code, and it works flawlessly. Again, thank you!
p.s. I just realized one of my references is a copy of your kernel I stumbled upon last week.
I had my page tables rooted at 0x9c000 (that was the example address given in a document I was referencing, and I never bothered to change it.) Once it got a few tables in, it overflowed into the 0xa0000 region. I never noticed anything, because I'm not using a graphics mode, yet. Just updated my code, and it works flawlessly. Again, thank you!
p.s. I just realized one of my references is a copy of your kernel I stumbled upon last week.