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 643273DA7FF for ; Tue, 2 Jun 2026 11:31:39 +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=1780399902; cv=none; b=bkWw95sJuiTc1G6AgsA4lYNDPFXEqxvlHIB65rwGGjw2TPmzFmPNgvuQ98YBy7XvnVoHwUebcavXINaEzqOyp/Z8O2eJi887M9qgSRqIC3hswECxSMrxVRkLiAZFKcsRK5J8dmWzTD/dJRZEOHxnFPhag5PTuxYs13x8KKTZ9Hk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780399902; c=relaxed/simple; bh=I6g87ifzKSC7xanWotJjcDH6wryDiBxkSs1jFel1RJM=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=c4UMUSzFBDDlL8TtUkN46+OBBxVh+QvclWYXPm2L6WUMyctc/zHYyulrbHtu/yDIuWByGGSAhmCBqOw7BnqmqX1Et9Y0dBYluQdLGY3hzvqRjaGtjAo4WxMdUgI1lKL+t3g2ZkaFW/BpMiqKHT4SCecpX8sbNRtgL+jnhnWMrPM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=XbYyeHyr; 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="XbYyeHyr" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13D2C1F00893; Tue, 2 Jun 2026 11:31:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1780399899; bh=HNUNOsRsaL4MX9fmPVTaRRjY40XM1Xv/juHezdNL9dA=; h=Date:Subject:From:To:Cc:References:In-Reply-To; b=XbYyeHyrCADWc2QJj7CfSsM93IQ9SgDVKuLEzy3CVu4SVVcUweAbiZUKzNdo62Ms4 vzrZlUtHaIWOQbncDY455ASVwvMOGpMJM1bcIBM6zJbyV0BtUfyN0necCg/w59yxmn VWQsXZa0j04Lrqtimj8udIRNo0qNN7J6N2sgPuzkKufNwEvfW8PS4OvsEjhdEciP6j D5+bu8UQwkUnpSoisJcTFE+JeZ35gh+fIbwt6PvBvbUvCzwNRvlJGa4MnTRk025RQa BERZy8cEcAPdWeSGMkOgwnw3abmYgTzmQ7stxfOIM6qxkdBIvabOqfwcNPaHIDvjYL pomYTpX/r90DA== Message-ID: Date: Tue, 2 Jun 2026 13:31:35 +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 From: "David Hildenbrand (Arm)" 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> <506fed6b-8954-40fa-8b5e-c8bd8c0d004b@kernel.org> Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit >> learn from obviously) against how mm works in practice. >> >> High review load with many overlapping changes might favour a different approach >> to a subsystem that looks different from that. > Yeah, but as we said, we discussed, it's all rather complicated and we should > move incrementally. > Starting to read Documentation/process/maintainer-tip.rst, it's very interesting: “The tip tree is both a direct development tree and and an aggregation tree for several sub-maintainer trees.” “In general, development against the head of the tip tree master branch is fine, but for the subsystems which are maintained separately, have their own git tree and are only aggregated into the tip tree, development should take place against the relevant subsystem tree or branch.” “Bug fixes which target mainline should always be applicable against the mainline kernel tree. Potential conflicts against changes which are already queued in the tip tree are handled by the maintainers.” So, yeah, let me reach out to understand what works, what doesn't work, and how it works :) -- Cheers, David