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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Mon, 7 Nov 2022 15:47:38 -0800
Message-ID: <CAHk-=wh6MxaCA4pXpt1F5Bn2__6MxCq0Dr-rES4i=MOL9ibjpg@mail.gmail.com>
Subject: Re: mm: delay rmap removal until after TLB flush
To:     Johannes Weiner <hannes@cmpxchg.org>
Cc:     Hugh Dickins <hughd@google.com>,
        Stephen Rothwell <sfr@canb.auug.org.au>,
        Alexander Gordeev <agordeev@linux.ibm.com>,
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On Mon, Nov 7, 2022 at 12:29 PM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> That said, if always doing the rmap removal under the page table lock
> means that that memcg lock can just be deleted in that whole path, I
> will certainly bow to _that_ simplification instead, and just handle
> the dirty pages after the TLB flush but before the page table drop.

Ok, so I think I have a fairly clean way to do this.

Let me try to make that series look reasonable, although it might be
until tomorrow. I'll need to massage my mess into not just prettier
code, but a sane history.

               Linus