Re: KASAN vs. boot-time switching between 4- and 5-level paging

[Andrey Ryabinin]

On 07/13/2017 05:15 PM, Kirill A. Shutemov wrote:

>>
>> Hm. I don't see this:
>>
>> ...
>> [    0.247532] 0xff9e938000000000-0xff9f000000000000      111104G                               p4d
>> [    0.247733] 0xff9f000000000000-0xffff000000000000          24P                               pgd
>> [    0.248066] 0xffff000000000000-0xffffff0000000000         255T                               p4d
>> [    0.248290] ---[ ESPfix Area ]---
>> [    0.248393] 0xffffff0000000000-0xffffff8000000000         512G                               p4d
>> [    0.248663] 0xffffff8000000000-0xffffffef00000000         444G                               pud
>> [    0.248892] ---[ EFI Runtime Services ]---
>> [    0.248996] 0xffffffef00000000-0xfffffffec0000000          63G                               pud
>> [    0.249308] 0xfffffffec0000000-0xfffffffefe400000         996M                               pmd
>> ...
>>
>> Do you have commit "x86/dump_pagetables: Generalize address normalization"
>> in your tree?
>>

Nope. Applied now, it helped.

>> https://git.kernel.org/pub/scm/linux/kernel/git/kas/linux.git/commit/?h=la57/boot-switching/v2&id=13327fec85ffe95d9c8a3f57ba174bf5d5c1fb01
>>
>>> As for KASAN, I think it would be better just to make it work faster,
>>> the patch below demonstrates the idea.
>>
>> Okay, let me test this.
> 
> The patch works for me.
> 
> The problem is not exclusive to 5-level paging, so could you prepare and
> push proper patch upstream?
> 

Sure, will do