Re: [PATCH AUTOSEL 4.20 072/117] btrfs: alloc_chunk: fix more DUP stripe size handling

[Sasha Levin]

On Wed, Jan 23, 2019 at 03:54:00PM +0000, Hans van Kranenburg wrote:
> On 1/23/19 3:37 PM, Sasha Levin wrote:
> > On Tue, Jan 08, 2019 at 11:52:02PM +0000, Hans van Kranenburg wrote:
> > > Hi Sasha,
> > >
> > > On 1/8/19 8:25 PM, Sasha Levin wrote:
> > > > From: Hans van Kranenburg <hans.van.kranenburg@xxxxxxxxxx>
> > > >
> > > > [ Upstream commit baf92114c7e6dd6124aa3d506e4bc4b694da3bc3 ]
> > > >
> > > > Commit 92e222df7b "btrfs: alloc_chunk: fix DUP stripe size handling"
> > > > fixed calculating the stripe_size for a new DUP chunk.
> > >
> > > That one also ended up as:
> > >
> > > 4.14-stable
> > > 0136bd7238b2cb8238426af4183ed0b02165c3f9
> > >
> > > 4.9-stable
> > > 8890bae03f4dba1c2292e5445682b556af4e8f1b
> > >
> > > 4.4-stable
> > > 97c3e46ef53748278286fc09dcc30b138d6677c4
> > >
> > > 3.16.57-rc1
> > > f68f46284a199f6837c1d5b94a6ae979a2cc463c
> > >
> > > While hitting the failure condition without adding "crafting" steps to
> > > make it exactly match the scenario is unlikely, it might be good if we
> > > just go all the way back with this regression fix?
> >
> > What do you mean with "all the way back"?
>
> Oh, apologies for not using unambigious phrasing.
>
> I mean, it seems the autoselection only found 92e222df7b in places where
> it's actually called 92e222df7b, and not where it was cherry-picked.
>
> So, for my own understanding: If I have to do something like this ever
> again, then should I have added it like this inside baf92114c?
>
> Fixes: 92e222df7b ("btrfs: alloc_chunk: fix DUP stripe size handling")
> Fixes: 0136bd7238 ("btrfs: alloc_chunk: fix DUP stripe size handling")
> Fixes: 8890bae03f ("btrfs: alloc_chunk: fix DUP stripe size handling")
> Fixes: 97c3e46ef5 ("btrfs: alloc_chunk: fix DUP stripe size handling")
> Fixes: f68f46284a ("btrfs: alloc_chunk: fix DUP stripe size handling")
>
> Thanks for your patience, :)

Ah, the scripts have enough "brains" to deal with these on their own, so
no need to annotate that much.

This patch wasn't applied to older trees because it didn't cherry-pick
cleanly on top of them. Looking at it now, it seems to depend on
793ff2c88c6 ("btrfs: volumes: Cleanup stripe size calculation") which
can possibly be picked up if it makes sense.

--
Thanks,
Sasha