Re: [PATCH 4.19 19/71] btrfs: extent_io: add proper error handling to lock_extent_buffer_for_io()

[Sasha Levin]

On Wed, Nov 11, 2020 at 02:39:34PM +0000, Ben Hutchings wrote:
> On Wed, 2020-11-11 at 13:44 +0100, Pavel Machek wrote:
> > Hi!
> >
> > > Thankfully it's handled by the only caller, btree_write_cache_pages(),
> > > as later write_one_eb() call will trigger submit_one_bio().  So there
> > > shouldn't be any problem.
> >
> > This explains there should not be any problem in _the
> > mainline_. AFAICT this talks about this code. Mainline version is:
> >
> >  prev_eb = eb;
> >  ret = lock_extent_buffer_for_io(eb, &epd);
> >  if (!ret) {
> >  	free_extent_buffer(eb);
> >  	continue;
> >  } else if (ret < 0) {
> >  	done = 1;
> >  	free_extent_buffer(eb);
> >  	break;
> >  }
> >
> > But 4.19 has:
> >
> >  ret = lock_extent_buffer_for_io(eb, fs_info, &epd);
> >  if (!ret) {
> >   	free_extent_buffer(eb);
> >  	continue;
> >  }
>
> That was changed in mainline two releases after this commit, though.
>
> > IOW missing the code mentioned in the changelog. Is 0607eb1d452d4
> > prerequisite for this patch?
>
> I think it's a separate fix, but probably worth picking too.

I'll take it in too, thanks!

--
Thanks,
Sasha