On 11/15/2017 09:19 PM, Linus Torvalds wrote:
> On Wed, Nov 15, 2017 at 3:33 AM, David Miller <da...@davemloft.net> wrote:
>>
>> Highlights:
>
> Lowlights:
>
> 1) it duplicated a commit from the hrtimer tree, which had been
> cleaned up and rewritten, but then merging the second copy of the
> commit re-introduced the bad code that had been cleaned up.
>
> I'm talking about commits
>
> - 7d9285e82db5:
> perf/bpf: Extend the perf_event_read_local() interface, a.k.a.
> "bpf: perf event change needed for subsequent bpf helpers"
> - 97562633bcba
> bpf: perf event change needed for subsequent bpf helpers
>
> where apparently there was no discussion between the groups about the
> subsequent changes.
>
> And this must have shown up in linux-next as a conflict, but no
> mention of it from either the perf event tree or the networking tree
> merge.
>
> Although it is of course possible that depending on merge order, the
> problem never showed up in next.
Sorry about that, it was discussed that the patch in [1] would get
routed through net-next and again cherry-picked from tracing folks
due to conflicting changes in perf event tree that were being worked
on to avoid later merge conflicts - clearly that didn't give the
desired result.
There was a subsequent discussion in [2] but not sure if cherry-picking
0d3d73aac2ff ("perf/core: Rewrite event timekeeping") into net-next
would have made it better or worse. We'll have a bpf sub-tree up and
running soon for the next development cycle that can be pulled from
by different parties when needed; potentially this could reduce such
conflicts between trees in future. Sorry for the trouble.
Thanks,
Daniel
[1] https://patchwork.ozlabs.org/patch/821919/
[2] https://lkml.org/lkml/2017/11/1/53
