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Date:   Fri, 8 Apr 2022 11:17:47 -0300
From:   Jason Gunthorpe <jgg@nvidia.com>
To:     Joerg Roedel <joro@8bytes.org>
Cc:     Lu Baolu <baolu.lu@linux.intel.com>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Alex Williamson <alex.williamson@redhat.com>,
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        Kevin Tian <kevin.tian@intel.com>,
        Ashok Raj <ashok.raj@intel.com>, Will Deacon <will@kernel.org>,
        Robin Murphy <robin.murphy@arm.com>,
        Dan Williams <dan.j.williams@intel.com>, rafael@kernel.org,
        Diana Craciun <diana.craciun@oss.nxp.com>,
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        Chaitanya Kulkarni <kch@nvidia.com>,
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        Laurentiu Tudor <laurentiu.tudor@nxp.com>,
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        Jonathan Hunter <jonathanh@nvidia.com>,
        Li Yang <leoyang.li@nxp.com>,
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        iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org,
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Subject: Re: [PATCH v8 00/11] Fix BUG_ON in vfio_iommu_group_notifier()
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On Fri, Apr 08, 2022 at 04:00:31PM +0200, Joerg Roedel wrote:
> On Fri, Apr 08, 2022 at 09:23:52AM -0300, Jason Gunthorpe wrote:
> > Why rc3? It has been 4 weeks now with no futher comments.
>
> Because I start applying new code to branches based on -rc3. In the past
> I used different -rc's for the topic branches (usually the latest -rc
> available when I started applying to that branch), but that caused silly
> merge conflicts from time to time. So I am now basing every topic branch
> on the same -rc, which is usually -rc3. Rationale is that by -rc3 time
> the kernel should have reasonably stabilized after the merge window.

You might consider using a linear tree instead of the topic branches,
topics are tricky and I'm not sure it helps a small subsystem so much.
Conflicts between topics are a PITA for everyone, and it makes
handling conflicts with rc much harder than it needs to be.

At least I haven't felt a need for topics while running larger trees,
and would find it stressful to try and squeeze the entire patch flow
into only 3 weeks out of the 7 week cycle.

In any event, I'd like this on a branch so Alex can pull it too, I
guess it means Alex has to merge rc3 to VFIO as well?

Thanks for explaining

Jason