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 30706C7EE2F for ; Mon, 29 May 2023 17:42:52 +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:Content-Transfer-Encoding: Content-Type:MIME-Version:References:In-Reply-To:Message-ID:Subject:Cc:To: From:Date:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=rUdtr6r3PmoAaW6qIy5abu2LwEp/uvxptQKJhnykm/I=; b=G4uvjEtq426q14aqWRvpk6beZa /8RGmQI4HgaiQ3weOINTvxFDQ9nRCkfUvEG5GcD6vrNhr4Pj+l9bqyLjsbaGpOd4mdFp8Ld2+ikRb nLIZb40Oc048JMg+VVon8QLCb+/l19zg+bREvAxMtox8kFW4zP/l7muW4xXr1mIlTXk6INhdrok5N INYzbcpvKTypmSK+mH6OfGPoV6Gog4lvrbY7nSwMgLw4Wq1IfRx7F+F/E3S9vgksgfuFLBNlKJoVe d1l9A+mMY9y/2Wxn85DFK4OMNapZWMYW6sHSugc59Alt/zss74imTdZ/3/hNtjQW/EGnunI3p7uxY drwtSV0g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.96 #2 (Red Hat Linux)) id 1q3gtO-00BHkv-1Y; Mon, 29 May 2023 17:42:50 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.96 #2 (Red Hat Linux)) id 1q2iFX-004Umz-1w; Sat, 27 May 2023 00:57:40 +0000 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 110F761B07; Sat, 27 May 2023 00:57:39 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2E64BC433D2; Sat, 27 May 2023 00:57:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685149058; bh=3vBQ3hNzB1htnPz205IbCSBNbcAAWMD/jc/FlGUItp8=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=aLfMMwQjdwdNcKtVFIzBBfhEKhzY8608s+2D5qjQ0I+cctckwK72Fr7Ero4sCyOay M/qiFF+9oqlrfB5lFVHgvB/IQFsOfaf9ms4w4pJrRSwroXILirP80J7tw+IvtlmrB6 C+axsiXhIPb8oG6HjqUu7w30SCHCFMI12quWVnGd07HNn5WSmjsVZ80qw6vSUhzlYV EFiVNxsX5sNgu7rqArJbv4j1C2nsqWjTEvKw/tWgLNDZQKKWCIFaxsDirhg7FmbgbK bcJ2BPiFi68edlfm+RtL/oOWB1hkdQHSRtYO/JKM041QmrEIOMfmOFV+oB8n4stFXo EfbKoqmE3Uf6w== Date: Fri, 26 May 2023 17:57:36 -0700 From: Jakub Kicinski To: David Howells Cc: netdev@vger.kernel.org, "David S. Miller" , Eric Dumazet , Paolo Abeni , Willem de Bruijn , David Ahern , Matthew Wilcox , Jens Axboe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jeroen de Borst , Catherine Sullivan , Shailend Chand , Felix Fietkau , John Crispin , Sean Wang , Mark Lee , Lorenzo Bianconi , Matthias Brugger , AngeloGioacchino Del Regno , Keith Busch , Jens Axboe , Christoph Hellwig , Sagi Grimberg , Chaitanya Kulkarni , Andrew Morton , linux-arm-kernel@lists.infradead.org, linux-mediatek@lists.infradead.org, linux-nvme@lists.infradead.org, Alexander Duyck Subject: Re: [PATCH net-next 05/12] mm: Make the page_frag_cache allocator handle __GFP_ZERO itself Message-ID: <20230526175736.7e75dcf9@kernel.org> In-Reply-To: <20230524153311.3625329-6-dhowells@redhat.com> References: <20230524153311.3625329-1-dhowells@redhat.com> <20230524153311.3625329-6-dhowells@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230526_175739_684553_5A2FA524 X-CRM114-Status: GOOD ( 14.47 ) X-Mailman-Approved-At: Mon, 29 May 2023 10:42:39 -0700 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 Wed, 24 May 2023 16:33:04 +0100 David Howells wrote: > Make the page_frag_cache allocator handle __GFP_ZERO itself rather than > passing it off to the page allocator. There may be a mix of callers, some > specifying __GFP_ZERO and some not - and even if all specify __GFP_ZERO, we > might refurbish the page, in which case the returned memory doesn't get > cleared. I think it's pretty clear that page frag allocator was never supposed to support GFP_ZERO, as we don't need it in networking.. So maybe you're better off adding the memset() in nvme? CCing Alex, who I think would say something along those lines :) IDK how much we still care given that most networking drivers are migrating to page_poll these days.