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t=1780328735; bh=xbm/oC8nM/kIkBqtYVbNQp3+SXT63KXvW1SoKSpbcmY=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=cxuX6BBp409qhCzGhOiEKD+5ln0UoZjqvT79pO87a5nOtvYGts9RsNisid7pcLb6y 3KNj5x83nT1Y8M+0jhqd92e8WiWl8vm3UqABY0AXwm1Z06mFw10iZI1KxNY39AFVdx XX1VutBNycJ/wzu05KhsqQa50BOSRgxmDtgriFkqj4XeTVQ3W4tKF6j8xkDAF8jVe+ eFW+YKV2j/uxIoPgM9UkaRgcu188mF8yP4pEB7k4A3JJS6zaRXS6uWzXKmNfnzY0Jm 4LEqjCMcdHTpn0romN3sOO5Tooe8r2pzreKlyiRfV9oIYa3Lex2oq+CrGsC5mIgjdb VAmsaIdeDY1mA== Message-ID: <506fed6b-8954-40fa-8b5e-c8bd8c0d004b@kernel.org> Date: Mon, 1 Jun 2026 17:45:30 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: Process (was Re: [PATCH mm-hotfixes-unstable v18 00/14] khugepaged: add mTHP) collapse support To: Lorenzo Stoakes Cc: "Vlastimil Babka (SUSE)" , Nico Pache , akpm@linux-foundation.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, liam@infradead.org, mhocko@suse.com, rppt@kernel.org, vbabka@suse.cz, willy@infradead.org References: <20260522150009.121603-1-npache@redhat.com> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 37D97120012 X-Stat-Signature: b75zh39ig8feimzqjbtjq4k588ayphia X-Rspamd-Server: rspam03 X-Rspam-User: X-HE-Tag: 1780328736-958436 X-HE-Meta: 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 SD3fAVjZ 7Cy3t5/2Zs3ZaEfh4DCgZqoXEtzgjicdRPkyD1Eju9Etlxz2++aOHeyj6Xc2SmwOTV7F1fEV865p1nxduabe6WsEbpCI98gbJ9La0fYI//qvuN5G7aVyKXHlPGeFLT5EvozXbYV4zLnSMti74liXfJOf4JxZdwx5l1Vv7yg/AdIoawhmZjtAjG6qa3zaX5LVfl0xG/ing/5EAuLWvEf+5MyEUtcr9cE8QNgynwM78m/FQvvHSaiCush6jeKzPXSpa9KDJ Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/1/26 17:41, Lorenzo Stoakes wrote: > On Sun, May 31, 2026 at 09:49:02PM +0200, David Hildenbrand (Arm) wrote: >>> >>> >>> This I'm not so sure how it would work. Assuming we have submaintainers with >>> their trees and branches, the final "stable branch" is merged from those. >>> But it's not a good base for work targeting the same merge window, as that >>> work would likely go to one of those submaintainer trees. But then it can't >>> be based on the result of merge of all submaintainer trees. That could only >>> work for patches targetting the next cycle (after the stable branch becomes >>> part of rc1). >>> >>> So either patches can be based on rc1 and applied as topic branches in a >>> submaintainer tree and then merged, or if they really depend on something >>> already in a submaintainer tree, then based on the respective topic branch >>> that's part of it. >> >> Right, most patches can be sent against the "stable branch", but cherry-picked >> on a submaintainers branch / topic tree. > > I think life will be easier with submaintainer separate trees for this honestly > :) or it could become a horrible mess in one tree I think. Requiring contributors to submit stuff targeted at some random trees is madness :) > > I think the simplest is what I suggested in reply to Vlasta, where each > submaintainer tree has their own set of changes against mm-next/mm-stable and > then we merge each week. Throw in hotfixes and it already starts being crazy. > > But am open to learning about what other subsystems in the kernel do... The TIP tree has a pretty elaborate model of dealing with topic branches, and don't require things to be sent against specific topic branches. I'll try to understand that model. -- Cheers, David