From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2917D318EE7; Mon, 13 Apr 2026 10:57:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776077872; cv=none; b=kzEHKpKt4jzwV8i9u15e2gxOgDNnMyKJAaWlbM72cSiy5hZV6NG85QMEU1BElWjONOqqK+qg1v3WW8HZq9F+Cm1M9w3vLKayboMMxOB06ROUJqX3gB2yH1bvlEcPLqO9wJlsAOcM/Ex0t3tx6aP3393CrtQbnPWPXFVz6UY0ubk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776077872; c=relaxed/simple; bh=rEMbzudmsD/Ya1O80dV5iRsZi+MxAj/TxZXg3yTLXlk=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=Hi8bej9UxigkMBnneOR3YAz/IWpQvw+T790EuiPCJ5paSaVJEF5yKFeek8FKWsI7fzlsMz6XDblLKwukQWf2fGMZnKdQK4GjpOM7PHuD4faMku0VgK1zHPS5yH8Fgjr2UHzQ0mtiSdkGRbauk4E9Tbg7iJ7AgDSRJxZPiBsI8t8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Bn845dOv; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Bn845dOv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 81A54C116C6; Mon, 13 Apr 2026 10:57:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776077871; bh=rEMbzudmsD/Ya1O80dV5iRsZi+MxAj/TxZXg3yTLXlk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Bn845dOvssdgWYOQcLe4tR0YlF03pQvtFLF4zl9wYL9luEriRkZKW9a9IBSgQ8KF5 D/7mUGIFVbG7oTR0s207eM21SA8wJ4eEvwe8niCwVoOHdXqxHieRW1Sc9NFuTzm6Oq OL5T43yiaOOymd/IK9L1KoapTK2P5oyRBRqeU1Ns= Date: Mon, 13 Apr 2026 12:57:49 +0200 From: Greg Kroah-Hartman To: Konrad Dybcio Cc: Andreas Noever , Mika Westerberg , Yehezkel Bernat , Gil Fine , Mika Westerberg , linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Konrad Dybcio Subject: Re: [PATCH RFC] thunderbolt: Skip reading Rsvd SB registers on older-gen hardware Message-ID: <2026041338-family-sprung-f69c@gregkh> References: <20260413-topic-usb4_limit_sb_reads-v1-1-778a6eb37f7b@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-usb@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20260413-topic-usb4_limit_sb_reads-v1-1-778a6eb37f7b@oss.qualcomm.com> On Mon, Apr 13, 2026 at 12:54:41PM +0200, Konrad Dybcio wrote: > From: Konrad Dybcio > > The Linux TBT subsystem supports hardware aligned with the latest > USB4 v2.0 specification. In some places though, it assumes registers > only defined in that specification version (previously marked as > Reserved) are always accessible. > > Every version of the spec states: > > """ > Unless specified otherwise, the Connection Manager shall not write a > register with a value that is marked as “Rsvd”. Writing a register with > a value that is marked as “Rsvd” results in undefined behavior. > """ > > The effective list of SB registers that need this guarding currently > exclusively contains ones that aren't used outside the debugfs dump > logic, so just add the required checks there. > > Fixes: 54e418106c76 ("thunderbolt: Add debugfs interface") > Signed-off-by: Konrad Dybcio > --- > drivers/thunderbolt/debugfs.c | 20 ++++++++++++-------- > drivers/thunderbolt/retimer.c | 11 ++++++++++- > drivers/thunderbolt/sb_regs.h | 11 ++++++----- > drivers/thunderbolt/tb.h | 2 ++ > 4 files changed, 30 insertions(+), 14 deletions(-) > Hi, This is the friendly patch-bot of Greg Kroah-Hartman. You have sent him a patch that has triggered this response. He used to manually respond to these common problems, but in order to save his sanity (he kept writing the same thing over and over, yet to different people), I was created. Hopefully you will not take offence and will fix the problem in your patch and resubmit it so that it can be accepted into the Linux kernel tree. You are receiving this message because of the following common error(s) as indicated below: - You have marked a patch with a "Fixes:" tag for a commit that is in an older released kernel, yet you do not have a cc: stable line in the signed-off-by area at all, which means that the patch will not be applied to any older kernel releases. To properly fix this, please follow the documented rules in the Documentation/process/stable-kernel-rules.rst file for how to resolve this. If you wish to discuss this problem further, or you have questions about how to resolve this issue, please feel free to respond to this email and Greg will reply once he has dug out from the pending patches received from other developers. thanks, greg k-h's patch email bot