From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail.tipi-net.de (mail.tipi-net.de [194.13.80.246]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 114BB2D0C92; Fri, 2 Oct 2026 14:59:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=194.13.80.246 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790953202; cv=none; b=az0kzXrLst7bzUAcMB0mOA5sy8KWtOEjo3Wi4NBg7Dj99gByGvV43pph3fqUDunA1GToJ+KCuTIREwdnG1XJrKB24baa7PjG8KsGNtXial7kVCkrA442G0pX7TChBWn9YwIdu9phvxdR3MyIEY0SLTMd20s/9As4DHiZYS6KD8A= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790953202; c=relaxed/simple; bh=gPpfEYoQDXiKMurcBkxxhaoyk9+LOrizdBTSMV0u32s=; h=MIME-Version:Date:From:To:Cc:Subject:In-Reply-To:References: Message-ID:Content-Type; b=Cig+PE8fLnrYc8Bm1ddkhGAXFPvlr9kb8bqfSp+V5NBB0cZ7Mul6r7hrGlT76YngGS54GYD71V2mI8Djp7qLkOykCTKycHc8NxemClkMitP/YIjDtflaQdhuJBfi2GeIXqtdc3H+ViRQbyssbQG9N8rWW+SO7GBGGSS0bnGN7Bs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de; spf=pass smtp.mailfrom=tipi-net.de; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b=hiYO379a; arc=none smtp.client-ip=194.13.80.246 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=tipi-net.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=tipi-net.de header.i=@tipi-net.de header.b="hiYO379a" 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== Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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