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Date:   Fri, 21 Jul 2023 22:51:44 +0500
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Cc:     Muhammad Usama Anjum <usama.anjum@collabora.com>,
        Andrei Vagin <avagin@gmail.com>,
        Danylo Mocherniuk <mdanylo@google.com>,
        Alex Sierra <alex.sierra@amd.com>,
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        "Liam R . Howlett" <Liam.Howlett@oracle.com>,
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        kernel@collabora.com
Subject: Re: fs/proc/task_mmu: Implement IOCTL for efficient page table
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From:   Muhammad Usama Anjum <usama.anjum@collabora.com>
In-Reply-To: <ZLpsEGZkeQECO08M@qmqm.qmqm.pl>
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On 7/21/23 4:29 PM, Michał Mirosław wrote:
> On Fri, Jul 21, 2023 at 03:48:22PM +0500, Muhammad Usama Anjum wrote:
>> On 7/21/23 12:28 AM, Michał Mirosław wrote:
>>> This is a massaged version of patch by Muhammad Usama Anjum [1]
>>> to illustrate my review comments and hopefully push the implementation
>>> efforts closer to conclusion. The changes are:
>> Thank you so much for this effort. I also want to reach conclusion. I'll
>> agree with all the changes which don't affect me. But some requirements
>> aren't being fulfilled with this current design.
> [...]
>> #define PAGE_IS_WPASYNC		(1 << 0)
>> #define PAGE_IS_WRITTEN		(1 << 1)
>> You have another new flag PAGE_IS_WPASYNC. But there is no application of
>> PAGE_IS_WPASYNC. We must not add a flag which don't have any user.
> 
> BTW, I'm not sure I got the PAGE_IS_WPASYNC naming right - this is to
> designate pages that can be write-protected (are UFFD-registered I believe).
PAGE_IS_UFFDWP_REGISTERED or PAGE_IS_WP_REG?

> 
> Best Regards
> Michał Mirosław

-- 
BR,
Muhammad Usama Anjum