From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from vps0.lunn.ch (vps0.lunn.ch [156.67.10.101]) (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 E220B1A6811; Tue, 2 Jun 2026 12:00:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=156.67.10.101 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780401645; cv=none; b=B/IVzrr15zU+kJbKeVCRa7KRXOnodAFFs4j/E6gDsjW6J4RwrIOxjSgPC0m3CmooT7BcVhWHoRHtrN+dGXByDTrDFZxRnVB0j1MTGBetN67oc6nR6msWC0bNoZ34cWSnh/OM0qXBe9phz9Yhr5NhSDY+LeBlPldxtmxGl4kOMAA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780401645; c=relaxed/simple; bh=dp/+iTiMz/pYNi6L4RRQ99sAGDeVwl5l1xsDeVbOQTU=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=MmFrRBehqvP4C5njURVBqTQAvz4ozvz2+DUcpFQEktZM3lrwhkP2JEH7HQep2uRgUV6wZxu3KjYCDMPSXxCMF98CrgKXYOkxjtR+Q8NozPfBmiW5oWLYeOEnCKv6qdEn+JXsS8vBXdumsK8Ik7AUJZU8cop+J42jDT7Z3jv3lSk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch; spf=pass smtp.mailfrom=lunn.ch; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b=EYoNokPl; arc=none smtp.client-ip=156.67.10.101 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=lunn.ch Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=lunn.ch Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=lunn.ch header.i=@lunn.ch header.b="EYoNokPl" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=bn3LblJfFEjiEa9uJvceLp7cBlrJ+F3kSsh0sE2DqjY=; b=EYoNokPlfnajWTjb4XeaAngiZb jIsVOnLIDiPkCiNavnXKcEDl9lI3Lz40Xh8mtufqQr5TyrdMj+1FbdBxdnxeVZ2msD0WjbfaG1+zh F/Fq0fFLfEGaGqCa+FjI3ZTMNDKrbmNViMTzZlrYPJABkhQrWQf9JQHkfr85ny8gtCTY=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1wUNnF-005gEI-SG; Tue, 02 Jun 2026 14:00:25 +0200 Date: Tue, 2 Jun 2026 14:00:25 +0200 From: Andrew Lunn To: Selvamani Rajagopal Cc: Piergiorgio Beruto , "parthiban.veerasooran@microchip.com" , "andrew+netdev@lunn.ch" , "davem@davemloft.net" , "edumazet@google.com" , "kuba@kernel.org" , "pabeni@redhat.com" , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" Subject: Re: [PATCH net-next v3 08/14] net: ethernet: oa_tc6: Remove FCS size in RX frame Message-ID: <93ae38dd-344a-4f65-945c-babebef4fbea@lunn.ch> References: Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Tue, Jun 02, 2026 at 02:40:13AM +0000, Selvamani Rajagopal wrote: > > > > On Fri, May 29, 2026 at 06:41:00PM +0000, Selvamani Rajagopal wrote: > > > When MAC-PHY appends FCS to the incoming frame, FCS, > > > it is removed from the frame before passing it to the stack. > > > > What is missing from this commit message is an answer to the question > > "Why?". Does the stack do something wrong if there is a FCS at the end > > of the frame? > > That was a little mystery to me as well when our SQA alerted me with the issue. > When I tested, ping worked fine without any issue even with the frames with FCS appended. > But strangely ptp4l utility failed with invalid data size. Once we removed FCS, it worked fine. > > Will add this reason in the commit message. Please take a look at NETIF_F_RXFCS. Andrew