Will UEFI enable 5-level-paging?

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wishedtobe
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Will UEFI enable 5-level-paging?

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Does the fact that the forum does not declare this mean that it can do whatever it likes?
nullplan
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Re: Will UEFI enable 5-level-paging?

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I should think that it won't. This way, it can keep booting operating systems that don't know about LA57. Also, I think Linux doesn't expect LA57 to be enabled at that point, and that's the only OS with 5-level support I can look at the source code for.
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zaval
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Re: Will UEFI enable 5-level-paging?

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wishedtobe wrote: Sat Oct 19, 2024 8:36 pm Does the fact that the forum does not declare this mean that it can do whatever it likes?
What exactly do you expect from UEFI to "declare" about 5 level mapping? It says, that for x64 it runs in 64 bit long mode, which means paging is on. What number of levels that 64 bit long mode is: 4 or 5 will depend on the platform. and what YOUR OS and its loader will decide to go with is fully on them, what UEFI does have to do with it? It stops owning the platform along with memory after you exit boot services and set your cr3 up (and other things, but since you worry about mapping, I mentioned it). Btw, is the 5 level translation really your OS's current most relevant, on time problem? Wow, this gives a feeling, like I'm reading osdev from 2055. 😁
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wishedtobe
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Re: Will UEFI enable 5-level-paging?

Post by wishedtobe »

zaval wrote: Tue Oct 22, 2024 7:07 pm What exactly do you expect from UEFI to "declare" about 5 level mapping? It says, that for x64 it runs in 64 bit long mode, which means paging is on. What number of levels that 64 bit long mode is: 4 or 5 will depend on the platform. and what YOUR OS and its loader will decide to go with is fully on them, what UEFI does have to do with it? It stops owning the platform along with memory after you exit boot services and set your cr3 up (and other things, but since you worry about mapping, I mentioned it).
If it does enable la57 and I don't know, treating it as a level 4 pagination, it may lead to a # page fault.
zaval wrote: Tue Oct 22, 2024 7:07 pm Btw, is the 5 level translation really your OS's current most relevant, on time problem? Wow, this gives a feeling, like I'm reading osdev from 2055. 😁
Bro, do I have to use 8086 to meet the requirements?
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