linux-kernel - Re: [PATCH v2 12/39] x86/mm: Update ptep_set_wrprotect() and pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE

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Message-ID: <64313344833c3b1701002a347d539e69276b66fb.camel@intel.com>
Date:   Mon, 3 Oct 2022 22:28:07 +0000
From:   "Edgecombe, Rick P" <rick.p.edgecombe@...el.com>
To:     "nadav.amit@...il.com" <nadav.amit@...il.com>
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Subject: Re: [PATCH v2 12/39] x86/mm: Update ptep_set_wrprotect() and
 pmdp_set_wrprotect() for transition from _PAGE_DIRTY to _PAGE_COW

On Mon, 2022-10-03 at 11:11 -0700, Nadav Amit wrote:
> Did you have a look at ptep_set_access_flags() and friends and
> checked they
> do not need to be changed too? 

ptep_set_access_flags() doesn't actually set any additional dirty bits
on x86, so I think it's ok.

> Perhaps you should at least add some
> assertion just to ensure nothing breaks.

You mean in ptep_set_access_flags()? I think some assertions would be
really great, I'm just not sure where.