From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AC3FAC27C53 for ; Wed, 5 Jun 2024 07:27:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:In-Reply-To:Content-Type: MIME-Version:References:Message-ID:Subject:Cc:To:From:Date:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=8LUykD/62bGMRfd/a9I1PHICud17UdPvZyyzW9ay8wM=; b=kBhJjpGtIgXYVkpxntHxoHrt+j 8o684NIYzgilW6WwO3Vflq7l0GyHQXpbetEyh5gQojYe2ulgyv9dlqStK00tXB1PQK235xxsLAr+L GgJ/f9SPtTXC9caL76SEA5Ehy6KIGMMFgbqf8VW0La66+0tueV9LDymdj7aQkD3tbshF9gc+/iB4w cFOd1bEleh8H7GIb4YC+2eqjBqEW5fLinL4M0H9ZKwHfPo1DDMySu8h2hajJ3BWpB3Sc4kyzrZJnF bn6AxrQi2DUf/G+2ny9SsOA7hkHB/Hg7iVwAFziP6KupXacisJTGHF+2kMyvrKH6hjiiFyYD6ARXY fy3d8UEg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sEl3m-000000050AR-16my; Wed, 05 Jun 2024 07:27:50 +0000 Received: from verein.lst.de ([213.95.11.211]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sEl3i-0000000509F-37xd for linux-nvme@lists.infradead.org; Wed, 05 Jun 2024 07:27:48 +0000 Received: by verein.lst.de (Postfix, from userid 2407) id 6002E68D0D; Wed, 5 Jun 2024 09:27:43 +0200 (CEST) Date: Wed, 5 Jun 2024 09:27:42 +0200 From: Christoph Hellwig To: Jakub Kicinski Cc: Christoph Hellwig , Ofir Gal , davem@davemloft.net, linux-block@vger.kernel.org, linux-nvme@lists.infradead.org, netdev@vger.kernel.org, ceph-devel@vger.kernel.org, dhowells@redhat.com, edumazet@google.com, pabeni@redhat.com, kbusch@kernel.org, axboe@kernel.dk, sagi@grimberg.me, philipp.reisner@linbit.com, lars.ellenberg@linbit.com, christoph.boehmwalder@linbit.com, idryomov@gmail.com, xiubli@redhat.com Subject: Re: [PATCH v2 0/4] bugfix: Introduce sendpages_ok() to check sendpage_ok() on contiguous pages Message-ID: <20240605072742.GA16306@lst.de> References: <20240530142417.146696-1-ofir.gal@volumez.com> <20240531073214.GA19108@lst.de> <20240601153610.30a92740@kernel.org> <20240604043041.GA28886@lst.de> <20240604074224.44668dab@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20240604074224.44668dab@kernel.org> User-Agent: Mutt/1.5.17 (2007-11-01) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240605_002747_077042_41EDC736 X-CRM114-Status: GOOD ( 11.96 ) X-BeenThere: linux-nvme@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Linux-nvme" Errors-To: linux-nvme-bounces+linux-nvme=archiver.kernel.org@lists.infradead.org On Tue, Jun 04, 2024 at 07:42:24AM -0700, Jakub Kicinski wrote: > I'd guess the thinking was that if we push back the callers would > switch the relevant allocations to be page-backed. But we can add > a comment above the helper that says "you'd be better off using > page frags and calling sendmsg(MSG_SPLICE_PAGES) directly". That's just not how network block devices or file systems work, they don't control the allocations and need to take what gets fed to them.