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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Tue, 5 Jan 2021 11:53:48 -0800
Message-ID: <CAHk-=wh=5kDGukMs2sVZ8uHZJX4VL13oD5+xMAR4HvuY6QckLg@mail.gmail.com>
Subject: Re: kernel BUG at mm/page-writeback.c:LINE!
To:     Hugh Dickins <hughd@google.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>,
        syzbot <syzbot+2fc0712f8f8b8b8fa0ef@syzkaller.appspotmail.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>
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On Tue, Jan 5, 2021 at 11:31 AM Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> On Mon, Jan 4, 2021 at 7:29 PM Hugh Dickins <hughd@google.com> wrote:
> >
> > > So the one-liner of changing the "if" to "while" in
> > > wait_on_page_writeback() should get us back to what we used to do.
> >
> > I think that is the realistic way to go.
>
> Yeah, that's what I'll do.

I took your "way to go" statement as an ack, and made it all be commit
c2407cf7d22d ("mm: make wait_on_page_writeback() wait for multiple
pending writebacks").

              Linus