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

[Andrey Ryabinin]

On 07/10/2017 03:33 PM, Kirill A. Shutemov wrote:

> 
> [Sorry for loong delay.]
> 
> The patch works for me for legacy boot. But it breaks EFI boot with
> 5-level paging. And I struggle to understand why.
> 
> What I see is many page faults at mm/kasan/kasan.c:758 --
> "DEFINE_ASAN_LOAD_STORE(4)". Handling one of them I get double-fault at
> arch/x86/kernel/head_64.S:298 -- "pushq %r14", which ends up with triple
> fault.
> 
> Any ideas?
> 
> If you want to play with this by yourself, qemu supports la57 -- use
> -cpu "qemu64,+la57".
> 

I'll have a look.