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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 048F1C77B60 for ; Sun, 23 Apr 2023 20:43:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229991AbjDWUnO (ORCPT ); Sun, 23 Apr 2023 16:43:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:46320 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229476AbjDWUnN (ORCPT ); Sun, 23 Apr 2023 16:43:13 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B402710CC for ; Sun, 23 Apr 2023 13:42:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1682282536; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=7QcY3a3kH0+Rq9gUuMPOzuma/qnGDgBISD5Gp0wCqpU=; b=gb+HIoUeLIOBkEaAgTXw+1aqqmGvqynD/h0OChsbYhCORq2nt4fRWj8a7ixuvxsiimNykq 9PWiS7J/NhRMjmylD8uwLpXV4Lv6q3NFsTNlur2/Y9Un60iz61CllVsnz/KAEQ2Pv55Z2i 6SFiOkkFeGJcOVkLwDsgmyOKgzq6p0c= Received: from mail-wr1-f72.google.com (mail-wr1-f72.google.com [209.85.221.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-610-8x20wIq7Ms2wECvSS51d1Q-1; Sun, 23 Apr 2023 16:42:15 -0400 X-MC-Unique: 8x20wIq7Ms2wECvSS51d1Q-1 Received: by mail-wr1-f72.google.com with SMTP id ffacd0b85a97d-2ef39671038so1084034f8f.2 for ; Sun, 23 Apr 2023 13:42:14 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682282534; x=1684874534; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=7QcY3a3kH0+Rq9gUuMPOzuma/qnGDgBISD5Gp0wCqpU=; b=KBg69c7WEENjh6hrSJf2zbUTdxqpT9VToOdDZ765TBFlyLPqH1w//xGSnrkiUPCfyW r57TwAGCFo2t2F0elGrC1v+MNFzu8EbFtcyr2DXgHbYMBFL9acWXM4DiygE8k/IoSDzz dJo/NBrS37YxO4IIS7KyPz36YW1tJWcqyX19R12YaQncq8ax/VCmIawERTXmRcujDCgr FSDG8nJjMyHnXyamKH1nacVUG3yXgFvE6FPJcayI6O5meLNk6WFB9AKTGOnMy5Mxc+nB eNkQxfCdZnIexz+Ek2Z068/QJ5gB7Z8zar7FDRiyk5mOFZqiFTbMsb9DHhR2l+qbd2uA XOOw== X-Gm-Message-State: AAQBX9dREdowQOQ2sFYQd2lhQe5ltEXUe0/YPyUCkhigNZ6rdRWPv20m xv5nm5WIVCGt/Z/1U0QFrusYzVBqyrEXybcUGE2KnbOWQq8bn0N3Pyf1QHFMn6YJ9eZ8T+JEan7 KoxwTqv2g4pLOYX3B X-Received: by 2002:a5d:4e01:0:b0:304:6715:8728 with SMTP id p1-20020a5d4e01000000b0030467158728mr4236852wrt.18.1682282533889; Sun, 23 Apr 2023 13:42:13 -0700 (PDT) X-Google-Smtp-Source: AKy350YdnKi+ZHb6STgweUlm/aZE45mVPCJXP21umah/V38ji93a8lhhwXhK5QKMqTIOSKpR49O6oQ== X-Received: by 2002:a5d:4e01:0:b0:304:6715:8728 with SMTP id p1-20020a5d4e01000000b0030467158728mr4236836wrt.18.1682282533574; Sun, 23 Apr 2023 13:42:13 -0700 (PDT) Received: from redhat.com ([2.55.17.255]) by smtp.gmail.com with ESMTPSA id c1-20020a5d4f01000000b002fc0de07930sm9307913wru.13.2023.04.23.13.42.09 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 23 Apr 2023 13:42:12 -0700 (PDT) Date: Sun, 23 Apr 2023 16:42:07 -0400 From: "Michael S. Tsirkin" To: Greg KH Cc: Xuan Zhuo , netdev@vger.kernel.org, =?iso-8859-1?Q?Bj=F6rn_T=F6pel?= , Magnus Karlsson , Maciej Fijalkowski , Jonathan Lemon , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , bpf@vger.kernel.org, virtualization@lists.linux-foundation.org, Jason Wang , Guenter Roeck , Gerd Hoffmann , Christoph Hellwig Subject: Re: [PATCH net-next v1] xsk: introduce xsk_dma_cbs Message-ID: <20230423161828-mutt-send-email-mst@kernel.org> References: <20230423062546.96880-1-xuanzhuo@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sun, Apr 23, 2023 at 08:45:20AM +0200, Greg KH wrote: > On Sun, Apr 23, 2023 at 02:25:45PM +0800, Xuan Zhuo wrote: > > The purpose of this patch is to allow driver pass the own dma callbacks > > to xsk. > > > > This is to cope with the scene of virtio-net. If virtio does not have > > VIRTIO_F_ACCESS_PLATFORM, then virtio cannot use DMA API. In this case, > > xsk cannot use DMA API directly to achieve DMA address. Based on this > > scene, we must let xsk support driver to use the driver's dma callbacks. > > Why does virtio need to use dma? That seems to go against the overall > goal of virtio's new security restrictions that are being proposed > (where they do NOT want it to use dma as it is not secure). Yes, they exactly use dma, specifically dma into bounce buffer.