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Date:   Sat, 21 Aug 2021 18:27:29 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     "Yu, Yu-cheng" <yu-cheng.yu@intel.com>
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Subject: Re: [PATCH v28 09/32] x86/mm: Introduce _PAGE_COW
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On Wed, Aug 18, 2021 at 09:38:30AM -0700, Yu, Yu-cheng wrote:
> We can visualize the type of a mm area by looking at vma->vm_flags, e.g.

visualize?

> maybe_mkwrite(), and PTE macros as lower-level operatives.  These two have
> some relations but not one-to-one.  Note that a PTE in a writable area is
> not always pte_write().
> 
> I have considered and implemented a shadow stack PTE either pte_write() or
> not.  Making shadow stack as pte_write() results in less arch_* macros and
> less confusion in copy-on-write code.  That is one more thing to consider.

Ok, even though I'm still not 100% convinced by both amluto's and your
arguments. Let's try it and see what happens...

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette