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 06ACD36AB46; Sat, 25 Jul 2026 15:55:15 +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=1784994919; cv=none; b=Xe6vScHtlFQught96IGwAvOODjRaB5lB3HlQlFd8vdQdM7VvAKLaPxMJd5sczpvCdG4F6oKi4u29QXhtAmEP/V/h+WdHJTeUfcRQNVbEgmEOIfVxX+eYlvvFN0DLl/nifk1YQeFVzD/i0/AxKLaMkcUOS1WVMXbX+IYAA1RLG5M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784994919; c=relaxed/simple; bh=yP10mmGUzrg/48obhb3r+1+xGk7SMUGXjV+yYmGclSk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rQxf6UMq+lrgnXjEou+Ypb8VocGi7o8RKekwSQPmv8mgP+Ybuxth8RFdaTLSCYjvX4ziHBTLZFgPpjUsTGlDTxNG2YGOHqXDInaBM9NGvhpwuMaWFcmC4/saHlzgcF0SN4mM2TKf/XC/GTEpPCVZ0i4KvI/Z48QiwWlEAzpaugs= 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=Q3ZcSQOE; 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="Q3ZcSQOE" 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=I/ImIEgfG79EqguJb0BUA/LECi0DJfTpT1YcXuMgOAQ=; b=Q3ZcSQOEtgB1Zd7o4V2PvQplNJ gmEXEMKQxYhfa78o4yEPbGkbI5YV1n/aDQj+8g8oZ+1S0b0rIsFcn5eVZKn/W32a9t2asxo2lPMli 1DJTQK8BQuveN5pU7PId/NEFax28JpstDDuI8ETjJ/CgPTinqmBPTuSHO59ARMSESUVg=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1wneiD-00E9uH-Io; Sat, 25 Jul 2026 17:54:53 +0200 Date: Sat, 25 Jul 2026 17:54:53 +0200 From: Andrew Lunn To: Jakub Kicinski Cc: Luke Howard , Richard Cochran , Vladimir Oltean , "David S. Miller" , Eric Dumazet , Paolo Abeni , Vivien Didelot , Gregory CLEMENT , Cedric Jehasse , Kieran Tyrrell , Max Holtmann , Max Hunter , Christoph Mellauner , Simon Gapp , netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH net-next v3 0/3] net: dsa: mv88e6xxx: various hwstamp fixes Message-ID: References: <20260719-mv88e6xxx-ptp-fixes-v3-0-161386ac8a62@padl.com> <20260724165207.6a03c9db@kernel.org> 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: <20260724165207.6a03c9db@kernel.org> On Fri, Jul 24, 2026 at 04:52:07PM -0700, Jakub Kicinski wrote: > On Sun, 19 Jul 2026 15:30:52 +1000 Luke Howard wrote: > > Three fixes for improving the reliably of hardware timestamp acquisition > > on Marvell switches. In our tests this eliminated missed timestamps in > > ptp4l, whilst also preserving PTP event and general message ordering on > > switches that support embedded timestamps. > > Do you know if there's any precedent in the existing upstream drivers > for overriding the reserved bytes? It's not normal for devices to modify > the ingress frames. Perhaps there's some precedent, but if not I think > we should gate this (eg with a devlink param?) > > Andrew, do you have any opinion? Or perhaps Richard? I have a dim memory of PHYs who change the packet by adding time stamps. There are definitely DSA switches which can put the stamps in the DSA header/trailer. Andrew