From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from invmail4.hynix.com (exvmail4.hynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 0FB27346E53; Tue, 11 Nov 2025 02:45:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.92 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762829116; cv=none; b=VBr3mhHnFVi0qg7M1qKpBj/GD7KG/o1KnQGC1GU5ZYi0mgsi0nDKntS+6ZFPqS/sJadbfkhucOYIBV0NIxiqRUxSLl/p8FhB0QyCm/S2JsTlkzh7NfaojOHrBF6dmLqe/t8Aa+hTSV5PUlcQePHDTuK0nPRUsQIn2ZXdxHSo1Lw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762829116; c=relaxed/simple; bh=rwaTaD8H95OEQUA2cvjGJVhLOhyYpCwkPUaKbmTZ/TY=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=uukIxRPQ2ipu2apLefbZQ8HoThmJNexlmP+EkY1quZFdUw0j2LDhU8jJ8oVZ5nMeJm/W+cfWm4I0JusERPImoDrsiHKkb+jryOeJCTMUKn1092AM7jtduMv5hNNIYES+vub6xnSjpXFXW1f5ROTj1uBbZeLbDCPxsnO90CoRIsg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-c2dff70000001609-21-6912a3311e0d Date: Tue, 11 Nov 2025 11:45:00 +0900 From: Byungchul Park To: Jakub Kicinski Cc: linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel_team@skhynix.com, harry.yoo@oracle.com, ast@kernel.org, daniel@iogearbox.net, davem@davemloft.net, hawk@kernel.org, john.fastabend@gmail.com, sdf@fomichev.me, saeedm@nvidia.com, leon@kernel.org, tariqt@nvidia.com, mbloch@nvidia.com, andrew+netdev@lunn.ch, edumazet@google.com, pabeni@redhat.com, akpm@linux-foundation.org, david@redhat.com, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, horms@kernel.org, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com, ilias.apalodimas@linaro.org, willy@infradead.org, brauner@kernel.org, kas@kernel.org, yuzhao@google.com, usamaarif642@gmail.com, baolin.wang@linux.alibaba.com, almasrymina@google.com, toke@redhat.com, asml.silence@gmail.com, bpf@vger.kernel.org, linux-rdma@vger.kernel.org, sfr@canb.auug.org.au, dw@davidwei.uk, ap420073@gmail.com, dtatulea@nvidia.com Subject: Re: [RFC mm v5 1/2] page_pool: check nmdesc->pp to see its usage as page pool for net_iov not page-backed Message-ID: <20251111024500.GA79866@system.software.com> References: <20251107015902.GA3021@system.software.com> <20251106180810.6b06f71a@kernel.org> <20251107044708.GA54407@system.software.com> <20251107174129.62a3f39c@kernel.org> <20251108022458.GA65163@system.software.com> <20251107183712.36228f2a@kernel.org> <20251110010926.GA70011@system.software.com> <20251111014052.GA51630@system.software.com> <20251110175650.78902c74@kernel.org> <20251111021741.GB51630@system.software.com> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251111021741.GB51630@system.software.com> User-Agent: Mutt/1.9.4 (2018-02-28) X-Brightmail-Tracker: H4sIAAAAAAAAA02SXUxTZxjH85739JzTYpPXCtsr3GxlCwlq3YgXD8n8uFlyLrZk2eKFumQW OUpjqaYgHyYmZdSgBJgbmpSCGUoGWIpI0dJWMVqwaE0cw8HOglIoExT5SgXCRyfjaMy8++f/ /+WX5+IRsO6hKlkwWfIlq8Vo1nMaVjO94dK2jAad6bO/QglQ1+bmoGWpCJpGfCpYdk8wUOfy IphfHuJhrSuE4FVPLwcvu2MIGi4tYqj73c7CQtsKBn9gAsGko5WDZ6EoDy2eryHSOM7CrbJO DNGf7nNQaV/F0LU8w8OPvuZ1cYeNhz5vlQrOr/yGodM2wsPjQB0Hw+41FYwHK1l44LzCwtyF HgyRqj0Qqv8AFh9OIehp62RgseIiBwM1AQZudA3wUN1fz8GYPYKgvzvKwoX4GQ5qS6oQrC6t K2fOzaug9t4wv8cglsgyJ3ZPzWLx+pW/GXHQ8TMryrfDjOh3PuXFes8JsaM5XSyX+7HocZ3l RE/sF158MniLE+87VlnRP5op+n2vGLGydIb7Jmm/5otsyWwqkKzbdx3U5LTJY/zxeELRZMVT 1oZ+VZcjtUDJDtrgucy/yyWxm5ySWfIpPdvX+qbnSBqV5WWs5ETyCbV31LDlSCNgMsdThzys UoZNJJ/OzdrWIUHQEqAtbr3C6MhtTMOPXIzCaMlG+qDmH1bJmKRT+fULRuExSaFNrwWlVpNM ejU4+UaZRFLpHW8vo3gomRfo9dM17NtDN9O7zTJ7DhHne1rne1rn/9p6hF1IZ7IU5BpN5h2G nGKLqchw6FiuB62/WOOp+AEfivV9F0REQPoNWvn5RpNOZSzIK84NIipgfaI2nkVMOm22sfik ZD32g/WEWcoLohSB1X+ozVgszNaRI8Z86agkHZes71ZGUCfbkGHrR/njB1JuVDPmsYqL+7aE ptyj1ea9j1O/igQ696YeMWxvbz84/e9p9eiEeXe07NrKx/FTQyOzQ2n7rV36zKzDBT5SuM9+ eLbHuxCtTQ2XhVtKd0U0XkvSlzmGbefTdBma3OHEnVPXlhxZf84ntH8/EHZ/ywTWmmO9tf7M 0B8uPZuXY/w8HVvzjP8BjLVwBF4DAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA02SbUhTYRiGec97ds5xtTgtXYeEoPUFiyyj4LEiin70EhQagX1RrTzkaC7b TLQIZg00S7MPYy4rS7Sps9UsdZZRm/nVl2jGkUxNK8tkiZk0lcoTRP27eO7rvn89HFaXK2Zx BlOSaDbpjVpGSSs3rzq5OLJQbVja8mop5LtdDJT9SIGbPdUKCLr6KcgvrUQwEnzDwq/aegTf 6hoY+OIfRlB4fRRD/ksbDd/dYxi8Nf0IBuzlDHyo72WhzLMJuos/0vAgvQpD79lGBrJs4xhq gwEWTlQ7J4crrCz4rzQpoKUyWwEXx4owVFl7WGiryWegy/VLAR99WTQ0OUpoGMqtw9CdvRbq CzQw+nQQQZ27ioLRM1cYaM+roeBebTsLF1oLGOizdSNo9ffSkDuRwcDltGwE4z8mJwM5Iwq4 /KSLXbuEpEkSQ/yDXzG5W9JBkdf2czSRHjZTxOt4y5ICzxFS4dSRTKkVE0/pKYZ4hs+zpPP1 A4Y02sdp4n0XRbzV3yiSdTLARGt2KFfHiUZDsmhesmavMt4t9bGJE1NSBs68pa3oWkgmCuEE frmQNnyfkZnm5wunWspZmRl+oSBJQSxzKD9PsFXk0ZlIyWF+iBXsUpdCDmbwScLQV+ukxHEq HoQyl1Z21PxDLDS/KKVkR8VPF5ry3tMyY14nSD8/U7KP+XDh5k9OPofwUcIt38CfyTB+rvCo soHKQSrHf23Hf23Hv3YBwqUo1GBKTtAbjCsiLAfjU02GlIj9hxI8aPKJio9PnKtGI20bfIjn kHaqSvo03aBW6JMtqQk+JHBYG6qa2Mcb1Ko4fepR0Xxoj/mIUbT4UDhHa2eqNsaKe9X8AX2S eFAUE0Xz35TiQmZZ0SrN7ZXKS9ZjcVHfmzft3BKo90fr5+xJT1i+8PCN29uKBnurWjQBf6F3 cWxOR9Gi3XWBsHXOGFNE8AlNbYBlMcGSO506e79q/fNpVzsanBej3/jO7xRjM3K53AWacGG7 Oia709mlm91/eL3tWbrrMcna5X6v2WJ6ZlyZsvU0sX/S0pZ4faQOmy3633ErMQVAAwAA X-CFilter-Loop: Reflected On Tue, Nov 11, 2025 at 11:17:41AM +0900, Byungchul Park wrote: > On Mon, Nov 10, 2025 at 05:56:50PM -0800, Jakub Kicinski wrote: > > On Tue, 11 Nov 2025 10:40:52 +0900 Byungchul Park wrote: > > > > > I understand the end goal. I don't understand why patch 1 is a step > > > > > in that direction, and you seem incapable of explaining it. So please > > > > > either follow my suggestion on how to proceed with patch 2 without > > > > > > > > struct page and struct netmem_desc should keep difference information. > > > > Even though they are sharing some fields at the moment, it should > > > > eventually be decoupled, which I'm working on now. > > > > > > I'm removing the shared space between struct page and struct net_iov so > > > as to make struct page look its own way to be shrinked and let struct > > > net_iov be independent. > > > > > > Introduing a new shared space for page type is non-sense. Still not > > > clear to you? > > > > I've spent enough time reasoning with out and suggesting alternatives. > > I'm not trying to be arguing but trying my best to understand you and > want to adopt your opinion. However, it's not about objection but I > really don't understand what you meant. Can anyone explain what he > meant who understood? If no objection against Jakub's opinion, I will resend with his alternaltive applied. Byungchul > Byungchul > > > If you respin this please carry: > > > > Nacked-by: Jakub Kicinski > > > > Until I say otherwise.