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Date:   Thu, 4 Mar 2021 17:58:49 +0100
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Anthony Iliopoulos <ailiop@suse.com>
Cc:     Jens Axboe <axboe@kernel.dk>,
        Andrew Morton <akpm@linux-foundation.org>,
        Matthew Wilcox <willy@infradead.org>, stable@vger.kernel.org,
        linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH STABLE 5.10 5.11] swap: fix swapfile page to sector
 mapping
Message-ID: <YEERyfs8QSB5lGVz@kroah.com>
References: <20210304150824.29878-1-ailiop@suse.com>
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 <YED5ypwsrExHWD7N@kroah.com>
 <YEELCJkGx78SP34d@technoir>
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On Thu, Mar 04, 2021 at 05:30:00PM +0100, Anthony Iliopoulos wrote:
> On Thu, Mar 04, 2021 at 04:16:26PM +0100, Greg Kroah-Hartman wrote:
> > On Thu, Mar 04, 2021 at 04:08:24PM +0100, Anthony Iliopoulos wrote:
> > > commit caf6912f3f4af7232340d500a4a2008f81b93f14 upstream.
> > 
> > No, this does not look like that commit.
> > 
> > Why can I not just take caf6912f3f4a ("swap: fix swapfile read/write
> > offset") directly for 5.10 and 5.11?  WHat has changed to prevent that?
> 
> You're right of course, the upstream fix applies even on v5.4 so you
> could just take it directly for those branches if this is preferable.

But, that commit says it fixes 48d15436fde6 ("mm: remove get_swap_bio"),
which is NOT what you are saying here in these patches.

So which is it?  Is there a problem in 5.11 and older kernels
(48d15436fde6 ("mm: remove get_swap_bio") showed up in 5.12-rc1), that
requires this fix, or is there nothing needed to be backported?

As a note, I've been running swapfiles on 5.11 and earlier just fine for
a very long time now, so is this really an issue?

confused,

greg k-h