Re: [PATCH v4 12/39] x86/mm: Update ptep_set_wrprotect() and pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE_COW

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To: "bp@xxxxxxxxx" <bp@xxxxxxxxx>
Subject: Re: [PATCH v4 12/39] x86/mm: Update ptep_set_wrprotect() and pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE_COW
From: "Edgecombe, Rick P" <rick.p.edgecombe@xxxxxxxxx>
Date: Tue, 27 Dec 2022 22:26:33 +0000
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In-reply-to: <Y6ryhvE3ev485oYC@zn.tnic>
References: <20221203003606.6838-1-rick.p.edgecombe@intel.com> <20221203003606.6838-13-rick.p.edgecombe@intel.com> <Y6ryhvE3ev485oYC@zn.tnic>
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On Tue, 2022-12-27 at 14:26 +0100, Borislav Petkov wrote:
> Just textual improvements:
> 
> On Fri, Dec 02, 2022 at 04:35:39PM -0800, Rick Edgecombe wrote:
> > From: Yu-cheng Yu <yu-cheng.yu@xxxxxxxxx>
> > 
> > When Shadow Stack is in use, Write=0,Dirty=1 PTE are reserved for
> > shadow
> 
> Pls, no caps.

Sure on "Shadow Stack". For Write=0,Dirty=1 there was a previous
suggestion to standardize on how these bits are referred to across the
series in both the comments and commit logs. I think the capitalization
helps differentiate between the concepts of write and dirty and the
actual PTE bits with those names. Especially since shadow stack muddies
the concepts of writable and dirty memory, I thought it was a helpful
distinction. Is it ok?

The other suggestions seem good.

Thanks,

Rick

Follow-Ups:
- Re: [PATCH v4 12/39] x86/mm: Update ptep_set_wrprotect() and pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE_COW
  - From: Borislav Petkov

References:
- [PATCH v4 00/39] Shadow stacks for userspace
  - From: Rick Edgecombe
- [PATCH v4 12/39] x86/mm: Update ptep_set_wrprotect() and pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE_COW
  - From: Rick Edgecombe
- Re: [PATCH v4 12/39] x86/mm: Update ptep_set_wrprotect() and pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE_COW
  - From: Borislav Petkov

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