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Date:   Sat, 21 May 2022 11:50:06 +0800
From:   Chih-En Lin <shiyn.lin@gmail.com>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
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Subject: Re: [RFC PATCH 2/6] mm: clone3: Add CLONE_COW_PGTABLE flag
Message-ID: <20220521035006.GB1506735@strix-laptop>
References: <20220519183127.3909598-1-shiyn.lin@gmail.com>
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On Fri, May 20, 2022 at 02:13:25PM +0000, Christophe Leroy wrote:
> 
> 
> Le 19/05/2022 ? 20:31, Chih-En Lin a ?crit?:
> > Add CLONE_COW_PGTABLE flag to support clone3() system call to enable the
> > Copy-On-Write (COW) mechanism on the page table.
> 
> Is that really something we want the user to decide ? Isn't it an 
> internal stuff that should be transparent for users ?
> 
> As far as I know, there is no way today to decide whether you want COW 
> or not for main memory. Why should there be a choice for the COW of page 
> tables ?

Agree.
It should not expose to the user.
COW of page table should become the configuration.
Or, if the change is fine, it can even be the default setting.

Thanks.

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Sorry I did not group reply the first time.