On Wed, Sep 23, 2020 at 10:23:51PM +0000, Song Liu wrote: > > > > On Sep 23, 2020, at 3:14 PM, Alexei Starovoitov <alexei.starovoitov@xxxxxxxxx> wrote: > > > > On Wed, Sep 23, 2020 at 02:48:24PM -0700, Andrii Nakryiko wrote: > >> On Wed, Sep 23, 2020 at 2:20 PM Alexei Starovoitov > >> <alexei.starovoitov@xxxxxxxxx> wrote: > >>> > >>> BPF developers, > >>> > >>> The merge window is 1.5 weeks away or 2.5 weeks if rc8 happens. In the past we > >>> observed a rush of patches to get in before bpf-next closes for the duration of > >>> the merge window. Then there is a flood of patches right after bpf-next > >>> reopens. Both periods create unnecessary tension for developers and maintainers. > >>> In order to mitigate these issues we're planning to keep bpf-next open > >>> during upcoming merge window and if this experiment works out we will keep > >>> doing it in the future. The problem that bpf-next cannot be fully open, since > >>> during the merge window lots of trees get pulled by Linus with inevitable bugs > >>> and conflicts. The merge window is the time to fix bugs that got exposed > >>> because of merges and because more people test torvalds/linux.git than > >>> bpf/bpf-next.git. > >>> > >>> Hence starting roughly one week before the merge window few risky patches will > >>> be applied to the 'next' branch in the bpf-next tree instead of > >> > >> Riskiness would be up to maintainers to determine or should we mark > >> patches with a different tag (bpf-next-next?) explicitly? > > > > "Risky" in a sense of needing a revert. The bpf tree and two plus -rc1 to -rc7 > > weeks should be enough to address any issues except the most fundamental ones. > > Something like the recent bpf_tail_call support in subprograms I would consider > > for the "next" branch if it was posted a day before the merge window. > > In practice, I suspect, such cases will be rare. > > > > I think bpf-next-next tag should not be used. All features are for [bpf-next]. > > Fixes are for [bpf]. The bpf-next/next is a temporary parking place for patches > > while the merge window is ongoing. > > I wonder whether we can move/rename the branch around so that the developers can > always base their work on bpf-next/master. Something like: > > Long before merge window for 5.15: > We only have bpf-next/master > > 1 week before merge window for 5.15: > Clone bpf-next/master as bpf-next/for-5.15 > > From -1 week to the end of merge window > Risky features only goes to bpf-next/master, bug fix goes in both master and for-5.15 > > After merge window: > Fast forward bpf-next/master based on net-next. Deprecate for-5.15. > > Would this work? It will create headaches for linux-next that merges bpf-next/master. All linux-next trees should not add patches to those trees that are not going into the merge window.
