| OSDev.org https://forum.osdev.org/ |
|
| My OS can only see ~3 GiB https://forum.osdev.org/viewtopic.php?f=1&t=57179 |
Page 1 of 2 |
| Author: | Xeno [ Fri Mar 22, 2024 4:05 pm ] |
| Post subject: | My OS can only see ~3 GiB |
My 64 Bit OS can only detect ~3-3.5 GiB ram If I use VBox it sees 3.5G if I use Qemu it only sees 3G My bootloader uses the INT 0x15, EAX = 0xE820 method to detect ram I have no other information, and am lost im this mess. |
|
| Author: | Octocontrabass [ Fri Mar 22, 2024 5:00 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Are you collecting the entire memory map? Are you reading all 64 bits of the addresses? |
|
| Author: | Xeno [ Fri Mar 22, 2024 5:12 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
I belive so, I send peramitors to the bios and send a pointer to the result to the kernel |
|
| Author: | Octocontrabass [ Fri Mar 22, 2024 5:14 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Have you tried looking at the memory map? Like, by printing it or something? |
|
| Author: | Xeno [ Fri Mar 22, 2024 5:29 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Yes, not priting the full thing but i did a print out of lengths and it shows exactly why my OS detects I am trying to work throught my boot code and do some checks there but I still have not found a solution |
|
| Author: | Octocontrabass [ Fri Mar 22, 2024 5:32 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
How much RAM did you configure in those VMs? |
|
| Author: | Xeno [ Fri Mar 22, 2024 5:34 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
i have tride at 4G but am curently trying with 8G I have tride between 32M and 24G in Vbox yet it only works up to 3.5G |
|
| Author: | Octocontrabass [ Fri Mar 22, 2024 5:36 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Can you print the whole memory map and share it? |
|
| Author: | Xeno [ Fri Mar 22, 2024 5:39 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Also VBox will freeze during initiation of page tables when its using more than 3GiB And I just noticed it crashes if I use exactly 2G This is only in VBox |
|
| Author: | Xeno [ Fri Mar 22, 2024 5:40 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Octocontrabass wrote: Can you print the whole memory map and share it? I can try but I will need to try to fix my crash problem too, as it messes with output |
|
| Author: | Xeno [ Fri Mar 22, 2024 5:46 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
VBox halts apon: Code: gas("movq %0, %%cr3" : : "r" (pt) :); when I am using more than 1G ram |
|
| Author: | Xeno [ Fri Mar 22, 2024 6:00 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Does VBox not suport 1GiB pages??? |
|
| Author: | Xeno [ Fri Mar 22, 2024 6:02 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
well iv figured out vbox, but not why i cant see more memory hm |
|
| Author: | Octocontrabass [ Fri Mar 22, 2024 6:06 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Xeno wrote: Does VBox not suport 1GiB pages??? It's an optional feature, you need to check CPUID before you try to use it. |
|
| Author: | Xeno [ Fri Mar 22, 2024 6:15 pm ] |
| Post subject: | Re: My OS can only see ~3 GiB |
Octocontrabass wrote: Xeno wrote: Does VBox not suport 1GiB pages??? It's an optional feature, you need to check CPUID before you try to use it. I realized my code is bad -_- Im still not able to fuigure out the first problem |
|
| Page 1 of 2 | All times are UTC - 6 hours |
| Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group http://www.phpbb.com/ |
|