Re: AMD boot woe due to "x86/mm: Cleanup pgprot_4k_2_large() and pgprot_large_2_4k()"

From: Borislav Petkov
Date: Wed Apr 22 2020 - 12:18:06 EST


On Wed, Apr 22, 2020 at 11:55:54AM -0400, Qian Cai wrote:
> Reverted the linux-next commit and its dependency,
>
> a85573f7e741 ("x86/mm: Unexport __cachemode2pte_tblâ)
> 9e294786c89a (âx86/mm: Cleanup pgprot_4k_2_large() and pgprot_large_2_4k()â)
>
> fixed crashes or hard reset on AMD machines during boot that have been flagged by
> KASAN in different forms indicating some sort of memory corruption with this config,
>
> https://raw.githubusercontent.com/cailca/linux-mm/master/x86.config

What is the special thing about this config? You have KASAN enabled and?
Anything else?

I need to know what are the relevant switches you've enabled so that I
can enable them on my box too and try to reproduce.

Thx.

--
Regards/Gruss,
Boris.

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