Received: by 2002:ac0:946b:0:0:0:0:0 with SMTP id j40csp1825461imj; Sun, 17 Feb 2019 15:50:50 -0800 (PST) X-Google-Smtp-Source: AHgI3IYviQHOne9xVKs1mCUXiX8RvH8bue2oSeys9AL0CHSwt18mbSo/YpGgE72ZG9wTtxo8HfQw X-Received: by 2002:a63:e74b:: with SMTP id j11mr16175337pgk.397.1550447450156; Sun, 17 Feb 2019 15:50:50 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1550447450; cv=none; d=google.com; s=arc-20160816; b=GCo0iP2+5i5zAeMpMFlPmlcTjCfVo3b/Hh734IaoSq5SmL8/hYZOuAgcvSieejEd2q TIAMN5XzT+eM3bVBqoohJBer4LUtTL/AqHdqq2hQwroDi0rRSLj+3ZLVcBn/r2o0UsVg GwsHNQiN/uyblnIA+hdgaa8H+7NWhej4wkDjhh3kQAp6EiQZmICOm7epje1rNU1qc0M7 VrVji2wZlVQs50//J5I4AeumRobJgfD2fM3xMsBEZyRH2XHySDHGgsDDUla3bcyyBoFA wzULgn3LqXDcD0UillR9GAn1FmMxMfqlPBUFphs3USwVxn0ySM47w/OweOrrsIrIndOt Xdrw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:from:subject:cc:to:message-id:date; bh=bG/NrotNBSsgK2Avqx8s7CINFwUkhQp5Xvzf6+L7uKY=; b=yOX+FYHrxrT6QjRG2A8MUmVy07MjuKtC4q8pv0s5BZPX//Jv2b2qGkU3OzlxWO+iAz GfpjkXCrozXqrkTmTswDMo9iBjx7JCL3/lIGaEun9CuoGuWRC8Ok9Rv/QUL9uaDadG++ 2ESAmdPiugkflkvq+wb+QEYMGvtAl6VDQEQJfH8nSlkel52gzWBOKGE+RLIazxFSLn0T sCeQ3zNxQEhr2GEllPHxrSAkFgvj3bJrq69qbKvDz8/vXFiMu5zoTqtvTR3oR3V/xm6V /pE3bFvayyCspzuexcHBZkk5Df9tSAejHXJdsUjDKvkPDHfRft2NgswcLD9IGrMSvc05 rVnQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id b17si9272205pfc.0.2019.02.17.15.50.33; Sun, 17 Feb 2019 15:50:50 -0800 (PST) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727660AbfBQXu2 (ORCPT + 99 others); Sun, 17 Feb 2019 18:50:28 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:42898 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726304AbfBQXu2 (ORCPT ); Sun, 17 Feb 2019 18:50:28 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 4359E1234135D; Sun, 17 Feb 2019 15:50:27 -0800 (PST) Date: Sun, 17 Feb 2019 15:50:26 -0800 (PST) Message-Id: <20190217.155026.2230689002634375366.davem@davemloft.net> To: alexander.duyck@gmail.com Cc: netdev@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, jannh@google.com Subject: Re: [net PATCH 0/2] Address recent issues found in netdev page_frag_alloc usage From: David Miller In-Reply-To: <20190215223741.16881.84864.stgit@localhost.localdomain> References: <20190215223741.16881.84864.stgit@localhost.localdomain> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sun, 17 Feb 2019 15:50:27 -0800 (PST) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexander Duyck Date: Fri, 15 Feb 2019 14:44:05 -0800 > This patch set addresses a couple of issues that I had pointed out to Jann > Horn in response to a recent patch submission. > > The first issue is that I wanted to avoid the need to read/modify/write the > size value in order to generate the value for pagecnt_bias. Instead we can > just use a fixed constant which reduces the need for memory read operations > and the overall number of instructions to update the pagecnt bias values. > > The other, and more important issue is, that apparently we were letting tun > access the napi_alloc_cache indirectly through netdev_alloc_frag and as a > result letting it create unaligned accesses via unaligned allocations. In > order to prevent this I have added a call to SKB_DATA_ALIGN for the fragsz > field so that we will keep the offset in the napi_alloc_cache > SMP_CACHE_BYTES aligned. Series applied, thanks Alexander.