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Date:   Thu, 9 Nov 2023 14:35:44 +0900
From:   Byungchul Park <byungchul@sk.com>
To:     Nadav Amit <namit@vmware.com>
Cc:     Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-mm <linux-mm@kvack.org>,
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Subject: Re: [v3 2/3] mm: Defer TLB flush by keeping both src and dst folios
 at migration
Message-ID: <20231109053544.GA75729@system.software.com>
References: <20231030072540.38631-1-byungchul@sk.com>
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On Mon, Oct 30, 2023 at 09:51:30PM +0900, Byungchul Park wrote:
> On Mon, Oct 30, 2023 at 08:50:20AM +0000, Nadav Amit wrote:
> > I do not follow the ordering that ensures a migrated page would not
> > become writable before the migration is over. Perhaps a comment on what
> > guarantees the order would help.

IIUC, it'd be safe because unmap is performed first at the beginning of
each migration so as to be safe with page fault handlers. So I don't
think it should be a concern. Or am I missing something?

	Byungchul