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Date:   Fri, 22 Feb 2019 18:25:25 +0100
From:   David Sterba <dsterba@suse.cz>
To:     Filipe Manana <fdmanana@kernel.org>
Cc:     Zygo Blaxell <ce3g8jdj@umail.furryterror.org>,
        linux-btrfs <linux-btrfs@vger.kernel.org>
Subject: Re: [PATCH 3/4] Btrfs: check if destination root is read-only for
 deduplication
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On Fri, Feb 22, 2019 at 11:13:48AM +0000, Filipe Manana wrote:
> So not doing nothing for now, that is, not applying this patch to
> disable dedupe on RO roots and wait for a better solution (best case,
> for 5.2 merge window), is reasonable
> and not something I'm against.
> David, would you consider at least excluding it from 5.1 to allow for
> a different solution to pop up for another merge window?

Ok, I'll remove it from the 5.1 queue for now. Thanks for the detailed
analysis. This fix favors send (for the correctness reasons), but the
deduplication usecase is also important. I hope we'll be able to come up
with a solution that does not hurt usability too much (or affects send
and dedupe equally with a sane fallback behaviour). The exclusion of
send and other operation (snapshot) already exists so the suggested
-EBUSY approach.