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 61D412DEA74; Tue, 21 Apr 2026 06:03:56 +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=1776751436; cv=none; b=KnaUPrBz7DF+yZgkL3GgkkE5bbUsi67+pzoLmlhz30/jewsJ+dNm82QjGZr8sujWgZdi0kl658gJ42dSzT9n3HRcP0suxPODDxaRbEOSjwML69ARhEuXRDUsfZEx3plxxpF4KOM5jnzMnb0RF7LovK9axIqpS9MaHY8+H0QtORU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1776751436; c=relaxed/simple; bh=39MG2Se+/eyfVMM8XJDbfOL9SLmB52vW2YmkOjx7r20=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=ikeQ0yO+rpVlDY8BeHTVP431rcxheDunb8FJgHZfQ68AH/93Pw0vaA63ZjkPTSzKT7F60ON/lX3HJ4CRLFtOItvOLjqO/tjeLaEsUntTtBDUpJ9cExj2pZtxk7wvGoZOXkRHMgseMxO+DkSuh1FnpCI47stF0iHaCtD7PsMMzRw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=bgmjUyCx; 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="bgmjUyCx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6839AC2BCB0; Tue, 21 Apr 2026 06:03:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1776751435; bh=39MG2Se+/eyfVMM8XJDbfOL9SLmB52vW2YmkOjx7r20=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=bgmjUyCxe1lDtznRkSQdMrrR5WAhkEdyjcYyknvtpLYZMokfXpFgYp5S8MmFmADwg +dxfqHOlEMagE/PLX1d+6Hv4yL7DkVwB/aHgeXv2fkYG1OxBw3sxHMq+YI3ZBkWJ7I +tGnwR/zN5LpYqZfvI6OO6veC1eV6qNHAhsdbDu4= Date: Tue, 21 Apr 2026 08:03:53 +0200 From: Greg KH To: Jakub Kicinski Cc: davem@davemloft.net, netdev@vger.kernel.org, edumazet@google.com, pabeni@redhat.com, andrew+netdev@lunn.ch, horms@kernel.org, corbet@lwn.net, skhan@linuxfoundation.org, marcel@holtmann.org, luiz.dentz@gmail.com, mchehab+huawei@kernel.org, jani.nikula@intel.com, demarchi@kernel.org, rdunlap@infradead.org, justonli@chromium.org, ivecera@redhat.com, jonathan.cameron@huawei.com, kees@kernel.org, marco.crivellari@suse.com, ferr.lambarginio@gmail.com, nihaal@cse.iitm.ac.in, mingo@kernel.org, tglx@kernel.org, linmq006@gmail.com, linux-doc@vger.kernel.org, linux-bluetooth@vger.kernel.org Subject: Re: [PATCH net-deletions] net: remove ISDN subsystem and Bluetooth CMTP Message-ID: <2026042144-crispness-perfected-6cff@gregkh> References: <20260421022108.1299678-1-kuba@kernel.org> Precedence: bulk X-Mailing-List: linux-bluetooth@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: <20260421022108.1299678-1-kuba@kernel.org> On Mon, Apr 20, 2026 at 07:21:07PM -0700, Jakub Kicinski wrote: > Remove the ISDN (mISDN, CAPI) subsystem and Bluetooth CMTP protocol > from the kernel tree. > > ISDN is a pretty old technology and it's unclear whether anyone still > uses it. I went over the last few years of git history and all the > commits are either tree-wide conversions or syzbot/static analyzer > fixes. > > When we discussed removal in the past IIRC there were some concerns > about ISDN still being used in parts of Germany. Unfortunately, the > code base is quite old, none of the current maintainers are familiar > with it and AI tools will have a field day finding bugs here. > > Delete this code and preserve it in an out-of-tree repository > for any remaining users: > https://github.com/linux-netdev/mod-orphan > > UAPI constants AF_ISDN/PF_ISDN and the SELinux isdn_socket class > are preserved for ABI stability, but the rest of uAPI is removed. > > Signed-off-by: Jakub Kicinski Acked-by: Greg Kroah-Hartman