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 9E022C77B72 for ; Mon, 17 Apr 2023 07:12:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229598AbjDQHMc (ORCPT ); Mon, 17 Apr 2023 03:12:32 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229461AbjDQHMb (ORCPT ); Mon, 17 Apr 2023 03:12:31 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 4762D40E2 for ; Mon, 17 Apr 2023 00:11:48 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1681715507; 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=3DxIGeDChpW+dCspX207xU3KDB22/OENqLPHBuTpQk8=; b=FesVfWKQwFZoCp87J5C24sRfjKKEnxwTZbodf7ktgqeswR8odoyfbuW5T8eZpkkKO2hBpd yzKAeE8P5Yj57zj/DpGZTrC627h7ZSFodzypPm/SZH7P4+Jwbi0nwo7zDdd6cto4yU588V MP4EL0KgV7n8wMELFY4ipo4el5/rYOQ= Received: from mail-qt1-f198.google.com (mail-qt1-f198.google.com [209.85.160.198]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-253-AELJAZQKOk-iOwm5GGVtDg-1; Mon, 17 Apr 2023 03:11:46 -0400 X-MC-Unique: AELJAZQKOk-iOwm5GGVtDg-1 Received: by mail-qt1-f198.google.com with SMTP id v24-20020a05622a189800b003e0e27bbc2eso17351353qtc.8 for ; Mon, 17 Apr 2023 00:11:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1681715506; x=1684307506; 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=3DxIGeDChpW+dCspX207xU3KDB22/OENqLPHBuTpQk8=; b=YllTfeVrRRhaalqBHE8br7+PidziU7ob+6Fe+PSgpPvKekF6BXXXzw34Z81wD9pLnc zNj60zxF6M+zuR4de/21vYM/BTvoKvHUxpQrW/YlPy5pCBUFc21ZRx1xX9TfxeBDuB8W qp4JdtN94j1ZlPdZIKofcnQa+IB+EWDqUj5/I0OWUT8YBndXIkoVs/V7kIRNCRYsMxXz DHUdgY/Jk8h0tr5U6xoC4BZH4WOAZZuyUaaC68+FYzFYqNdDQG0htrmCYUw1QIr5QS3t S2Akyoofyl6gJls/CI6xYUzyd44RlxkViHKBMcA7+pJALRGeTAETlkAuqIG0Of8RAdKm kQBQ== X-Gm-Message-State: AAQBX9cJeJmYINilepJKoTYEgyCJhC06Ezgu4SUB6BUkkk7WR0GgcavG nIh11FwUtL3NPKvI2KnlaiOQFzXD+ixbINkDF1MrQEuQroZt/giC0FM/AdsNGess5Nr99tkl00C GgOTj6LeovMxwIGf8 X-Received: by 2002:a05:622a:15c8:b0:3e6:7634:3d0a with SMTP id d8-20020a05622a15c800b003e676343d0amr20401076qty.1.1681715505870; Mon, 17 Apr 2023 00:11:45 -0700 (PDT) X-Google-Smtp-Source: AKy350bRWAwroeDDp+zaMLOKHGqZ0C7Fj+pnRJZLP5CoVXzD2w0JJpOmAxj/pZFif7P2SmN4qP2jFA== X-Received: by 2002:a05:622a:15c8:b0:3e6:7634:3d0a with SMTP id d8-20020a05622a15c800b003e676343d0amr20401058qty.1.1681715505638; Mon, 17 Apr 2023 00:11:45 -0700 (PDT) Received: from redhat.com ([185.199.103.251]) by smtp.gmail.com with ESMTPSA id z1-20020ac81001000000b003b9b8ec742csm3089121qti.14.2023.04.17.00.11.41 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Apr 2023 00:11:45 -0700 (PDT) Date: Mon, 17 Apr 2023 03:11:38 -0400 From: "Michael S. Tsirkin" To: Alvaro Karsz Cc: Xuan Zhuo , "davem@davemloft.net" , "edumazet@google.com" , "kuba@kernel.org" , "pabeni@redhat.com" , "virtualization@lists.linux-foundation.org" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , Jason Wang Subject: Re: [PATCH net] virtio-net: reject small vring sizes Message-ID: <20230417031052-mutt-send-email-mst@kernel.org> References: <20230416074607.292616-1-alvaro.karsz@solid-run.com> <20230416164453-mutt-send-email-mst@kernel.org> <20230417021725-mutt-send-email-mst@kernel.org> <1681713856.1928573-2-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 Mon, Apr 17, 2023 at 07:07:59AM +0000, Alvaro Karsz wrote: > > Why tx timeout without frags? > > Please see my response to Michael. > > > > * Guest GSO/big MTU (without VIRTIO_NET_F_MRG_RXBUF?), we can't chain page size buffers anymore. > > > > > > Or, we disable the GUEST_GSO, HOST_GSO...... > > > And disable VIRTIO_NET_F_MTU, quoting the spec: > "A driver SHOULD negotiate VIRTIO_NET_F_MTU if the device offers it." If you don't the nic can still get jumbo packets it will just drop them ... > We can find a way around using buffers bigger than a page size like Michael implied.