From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4ECE37DAA9 for ; Mon, 1 Jun 2026 15:45:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780328736; cv=none; b=eggQ+rPb0Lo9TZpqd18uL3NVvSZmAxwCBkIM0uUnMFetLeSbSdqfjnVNQfeKwH//2UPaW7nHiefLnYnsntVZBR3iUd4+Kp2+i7jt2Qq7fpSLofF5B7/QSzneoIqbwIDYVrHyHy79MZXGbp/ke7romSzMSHuvBiP7psGg78lVfIw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780328736; c=relaxed/simple; bh=xM3UPYu/7N9AM3lkH/Q3FGR6oxPhI1zZFsL37I2sCEY=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=b2554t2kUKEb89XhKAvvApSSuCXpNLeaR6PfyPdtU0QpIudl5Q6kBPJitSJY6SyPdxuQ76U/c2E+WUOpIIAOwJWihKbdil/D6XFHl8Jltth7zyVriuMBBKSJ1GpDLQTCyQnA0IazMnBNED4p/XtG4aHz6bOfF7nSnPIuVuVr3oQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=cxuX6BBp; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="cxuX6BBp" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7F8F31F00893; Mon, 1 Jun 2026 15:45:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; 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 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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