From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A36C738B7DD; Thu, 9 Apr 2026 08:14:39 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775722479; cv=none; b=Q7h+4oOcFxSnIKFAhslsVkq9T0Dfg4lNP/lrNYS3iUTEJIXFFkpPEQw6Trgqo/A3Ir8OV0/SgckMmcRKHhX2HAbG5WZ7oYucTZYt33Sg+4CxA9SfMWuTKoT+NvUVGIp/GXOwq0MKImI8uoU7wC7ymh8yHYDXtIiIfflGdv7YBDU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1775722479; c=relaxed/simple; bh=3G5Y64fdJYhpPq7ZwMBZEixlrfHpeuaE8YXrRUfjeMs=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=esAg1qeBVxxpCzH69ppNRBqQe1GnwOHDEQMTYTSy4WAjPGDCVqCDSgG8zEvePm3o4wxdTVrt9FyFB6cdUxNhgJ7e/NIbXSbIP8i7ub/fRtTXXaf9sRS5+Zew8DAmNnO0G1xudkH8JusFumh1SAiSupegdhsS+yRtNzN4mCkLVAU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=OzHoVBeR; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="OzHoVBeR" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CABD9C4CEF7; Thu, 9 Apr 2026 08:14:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1775722479; bh=3G5Y64fdJYhpPq7ZwMBZEixlrfHpeuaE8YXrRUfjeMs=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=OzHoVBeRvY/SsR06SwsiSiPOpUf/NeNeO4KCQ0hNXg00N+yKidPIAkYDUEm9IdNrk vDmreE9oiiil6bCPRhEF5TIaV1mw68kw+UTV3PZWmYnOatG48gpRcTxuLy9ItYjpDu YAUfI0+rdR/p6aO03Jj4W47eLSmjPhAxh0rOeFzu8ScWCrbR9K6YodD9JXmfUxC664 23hIyo1iVYlLo71vl+7Fg3stF4il+ImnBRfqZz24TFfGraJ8LbG5DJBTZHuzcWK5hg 9EPm1kjYUet+TSleyKr50u/2zBfC/jB9m2maCM8/sqitwoiNXOHAO34bYEb0Rr09iD UxfM9W1yZ++wA== Message-ID: <2e3f7c8c-c443-4e71-ad60-36c5203de09b@kernel.org> Date: Thu, 9 Apr 2026 10:14:21 +0200 Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH mm-unstable v15 03/13] mm/khugepaged: generalize __collapse_huge_page_* for mTHP support To: Nico Pache Cc: linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-trace-kernel@vger.kernel.org, aarcange@redhat.com, akpm@linux-foundation.org, anshuman.khandual@arm.com, apopple@nvidia.com, baohua@kernel.org, baolin.wang@linux.alibaba.com, byungchul@sk.com, catalin.marinas@arm.com, cl@gentwo.org, corbet@lwn.net, dave.hansen@linux.intel.com, dev.jain@arm.com, gourry@gourry.net, hannes@cmpxchg.org, hughd@google.com, jack@suse.cz, jackmanb@google.com, jannh@google.com, jglisse@google.com, joshua.hahnjy@gmail.com, kas@kernel.org, lance.yang@linux.dev, Liam.Howlett@oracle.com, lorenzo.stoakes@oracle.com, mathieu.desnoyers@efficios.com, matthew.brost@intel.com, mhiramat@kernel.org, mhocko@suse.com, peterx@redhat.com, pfalcato@suse.de, rakie.kim@sk.com, raquini@redhat.com, rdunlap@infradead.org, richard.weiyang@gmail.com, rientjes@google.com, rostedt@goodmis.org, rppt@kernel.org, ryan.roberts@arm.com, shivankg@amd.com, sunnanyong@huawei.com, surenb@google.com, thomas.hellstrom@linux.intel.com, tiwai@suse.de, usamaarif642@gmail.com, vbabka@suse.cz, vishal.moola@gmail.com, wangkefeng.wang@huawei.com, will@kernel.org, willy@infradead.org, yang@os.amperecomputing.com, ying.huang@linux.alibaba.com, ziy@nvidia.com, zokeefe@google.com References: <20260226031741.230674-1-npache@redhat.com> <20260226032347.232939-1-npache@redhat.com> <8a4568de-e0f9-471b-bc94-1062d4af3938@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; 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charset=UTF-8 Content-Transfer-Encoding: 8bit On 4/8/26 21:48, Nico Pache wrote: > On Thu, Mar 12, 2026 at 2:56 PM David Hildenbrand (Arm) > wrote: >> >> On 3/12/26 21:36, David Hildenbrand (Arm) wrote: >>> >>> Okay, now I am confused. Why are you not taking care of >>> collapse_scan_pmd() in the same context? >>> >>> Because if you make sure that we properly check against a max_ptes_swap >>> similar as in the style above, we'd rule out swapin right from the start? >>> >>> Also, I would expect that all other parameters in there are similarly >>> handled? >>> >> >> Okay, I think you should add the following: > > Hey! Thanks for all your reviews here. > > For multiple reasons, here is the solution I developed: > > Add a patch before the generalize __collapse.. patch that reworks the > max_ptes* handling and introduces the helpers (no functional changes). I assume that's roughly the patch I shared below? If so, sounds good to me. -- Cheers, David