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 96348CA5FC4 for ; Fri, 2 Oct 2026 15:00:26 +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:Message-ID:References:In-Reply-To:Subject:Cc:To:From:Date: MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=pXn703aOIjISemvjW7SqSYgESFNqSmJXUCU165M1Fr8=; b=cNZEseXEnHu1Gm8m3DKxjn5yTb DQi2SjLuak0qy4UfJlqzbsxzaLBOBtIdzRtsMYYU/2Tb6JRroPV/v+fK5Cq7TN6lQDlQM4PWG9rkL haapV7O7wBNzvCZLlmA/wn3gRGEhRQDm82F9ntJJGYZnyFYYZvrVlaACa1AD8ZhRIoHg+zva163fa XvEroGyijgHMdtDtW1uGHOYEhyI5YWKT2+Qe9MjvFvI0F8mcrm031bfNXVXKVHOFj0JpJ+e/QF7Bm +44X3Rm2xJTiKdV813xXyFrzfw8WdDkmnWS7OhTJW4o8JS5zKJWfqBg/qd2A+xKdkPOJ6zFxLw0Bv dHXFz6CQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xCek8-0000000Bpba-3fGW; Fri, 02 Oct 2026 15:00:12 +0000 Received: from mail.tipi-net.de ([2a03:4000:43:185::1]) by bombadil.infradead.org with esmtps (Exim 4.99.1 #2 (Red Hat Linux)) id 1xCek0-0000000BpR0-1Sqa for linux-arm-kernel@lists.infradead.org; Fri, 02 Oct 2026 15:00:07 +0000 Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 19413A4AB8; Fri, 2 Oct 2026 16:59:46 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=tipi-net.de; s=dkim; t=1790953193; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=pXn703aOIjISemvjW7SqSYgESFNqSmJXUCU165M1Fr8=; b=hiYO379a2JrVAMN12K+8M4nzv4aoMDawt/E/KmtAWiumBOaJXZ39gvhfuXkRj4zeZBnmdt u2P9So1KX+/VmAyvQzURenGsqL+NFRrj9JNGUsmKjx/WSGCh15gvHFnCIRKwA0GNC8tkxq 796xpxuzYZcJWmjnafK0pynf5N4P/+5f1HkB9s01q4APJwN+IjCSCcVyy3qhkL7uKzTc95 TQr9NJBdDF9BS4laG+WJiQPNqRlfHcrWluflKz528lsRy+hgCnGzSOJTTvWYsBEJ4tdmf+ daeBNC1XcB1+Ob0IppU2HipznxklPjF3JQYoEzMgtrzxrhCLUdRxN8TSRraZyA== MIME-Version: 1.0 Date: Fri, 02 Oct 2026 16:59:46 +0200 From: Nicolai Buchwitz To: Maxime Chevallier Cc: Andrew Lunn , Jakub Kicinski , davem@davemloft.net, Eric Dumazet , Paolo Abeni , Simon Horman , Maxime Coquelin , Alexandre Torgue , Russell King , Lorenzo Bianconi , Jitendra Vegiraju , thomas.petazzoni@bootlin.com, =?UTF-8?Q?Alexis_Lothor=C3=A9?= , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, Peter Robinson , Joe Damato Subject: Re: [PATCH net-next v3 1/3] net: rss: Require indir table size or hash key size to support RSS In-Reply-To: <20261002142806.1299041-2-maxime.chevallier@bootlin.com> References: <20261002142806.1299041-1-maxime.chevallier@bootlin.com> <20261002142806.1299041-2-maxime.chevallier@bootlin.com> Message-ID: X-Sender: nb@tipi-net.de Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit X-Last-TLS-Session-Version: TLSv1.3 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261002_080005_394624_AF45D4DC X-CRM114-Status: GOOD ( 15.65 ) X-BeenThere: linux-arm-kernel@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-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Maxime On 2.10.2026 16:28, Maxime Chevallier wrote: > A point can be made that devices that report a 0-size indirection table > and 0-length key size don't really support RSS. Let's return > -EOPNOTSUPP > in that case, and skip these devices during DUMP requests. > > This however also reports -ENOTSUPP for devices that only supports flow > hash fields ops now. nit: -EOPNOTSUPP > > Signed-off-by: Maxime Chevallier > --- > net/ethtool/ioctl.c | 6 ++++++ > net/ethtool/rss.c | 7 +++++-- > 2 files changed, 11 insertions(+), 2 deletions(-) > > diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c > index 27b0e2e275dc..d32b403c8d3a 100644 > --- a/net/ethtool/ioctl.c > +++ b/net/ethtool/ioctl.c > @@ -1444,6 +1444,9 @@ static noinline_for_stack int > ethtool_get_rxfh(struct net_device *dev, > if (ops->get_rxfh_key_size) > rxfh_dev.key_size = ops->get_rxfh_key_size(dev); > > + if (!rxfh_dev.indir_size && !rxfh_dev.key_size) > + return -EOPNOTSUPP; > + > if (copy_from_user(&rxfh, useraddr, sizeof(rxfh))) > return -EFAULT; > user_indir_size = rxfh.indir_size; > @@ -1554,6 +1557,9 @@ static noinline_for_stack int > ethtool_set_rxfh(struct net_device *dev, > if (ops->get_rxfh_key_size) > dev_key_size = ops->get_rxfh_key_size(dev); > > + if (!dev_indir_size && !dev_key_size) > + return -EOPNOTSUPP; > + > if (copy_from_user(&rxfh, useraddr, sizeof(rxfh))) > return -EFAULT; > > diff --git a/net/ethtool/rss.c b/net/ethtool/rss.c > index d4a1a4724b67..cb9bead0cedd 100644 > --- a/net/ethtool/rss.c > +++ b/net/ethtool/rss.c > @@ -129,6 +129,9 @@ rss_get_data_alloc(struct net_device *dev, struct > rss_reply_data *data) > if (ops->get_rxfh_key_size) > data->hkey_size = ops->get_rxfh_key_size(dev); > > + if (!data->indir_size && !data->hkey_size) > + return -EOPNOTSUPP; > + > indir_bytes = data->indir_size * sizeof(u32); > total_size = indir_bytes + data->hkey_size; > rss_config = kzalloc(total_size, GFP_KERNEL); > @@ -449,7 +452,7 @@ rss_dump_one_dev(struct sk_buff *skb, struct > netlink_callback *cb, > > if (!ctx->ctx_idx) { > ret = rss_dump_one_ctx(skb, cb, dev, 0); > - if (ret) > + if (ret && ret != -EOPNOTSUPP) > return ret; > ctx->ctx_idx++; > } > @@ -457,7 +460,7 @@ rss_dump_one_dev(struct sk_buff *skb, struct > netlink_callback *cb, > for (; xa_find(&dev->ethtool->rss_ctx, &ctx->ctx_idx, > ULONG_MAX, XA_PRESENT); ctx->ctx_idx++) { > ret = rss_dump_one_ctx(skb, cb, dev, ctx->ctx_idx); > - if (ret) > + if (ret && ret != -EOPNOTSUPP) > return ret; > } > ctx->ctx_idx = ctx->start_ctx; Reviewed-by: Nicolai Buchwitz Thanks, Nicolai