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 103FE29DB65; Mon, 26 Jan 2026 10:57:42 +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=1769425063; cv=none; b=ePnoDFZoIDWF91jPqdR7rGELjmsqj7lszsdtT6vCl0kPatL8JRBdtiWhEULt9XE3xMPYk2M4W9NVdkAE3sMm3UVyt6WSxYYhzT6S01g3KMIHL/5ZI+r4o4iMCCgmbuAgOqu3SXhN7dFOja5Uk9/hq6tK6iYVtmXyCBi1VcA2Q2Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1769425063; c=relaxed/simple; bh=4cUWKgDWAyrbhapIOlP0Fpin+tvQj1odqMn5yCM/w5o=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=VvxjvJ5/n8/qEZjN262kqSvYh+Qam/HjwDlq2rz/nqySLiWRTdI+eWdFqIoky872TeP5w7dFvUOjPYOqRCFlHDtwCKuDHdybi90vyGDovRp1C1DaicE77GV1OSt2bxAM8hA96NfZNC9fxXhP9ESTbL80UyeTr0b7iscIwnQRSTY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ZaJJkP9v; 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="ZaJJkP9v" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2A454C116C6; Mon, 26 Jan 2026 10:57:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1769425062; bh=4cUWKgDWAyrbhapIOlP0Fpin+tvQj1odqMn5yCM/w5o=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZaJJkP9v5mbAUiangXgTz/pSRV17AWDI8d1tJ1FqEHh+R9M3A78szLmLe+rlNwKUr P7cT7zaAUgwZIlrkg3cy0gi/pWmh6kATZQho1IB4W+UnxnA7gebaOWfWlwHY3j/Fwp AdWmPodM61nhWXZY4btS6bO5q8UcyxpzZpewK588= Date: Mon, 26 Jan 2026 11:57:39 +0100 From: Greg Kroah-Hartman To: Jocelyn Falempe Cc: Jiri Slaby , Nicolas Pitre , Calixte Pernot , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org Subject: Re: [PATCH] vt: Add enable module parameter Message-ID: <2026012604-yelling-hurdle-ebf9@gregkh> References: <20260126092234.713465-1-jfalempe@redhat.com> <2026012613-cotton-jellied-b67a@gregkh> <48be84fb-bee4-4a22-bde4-0d0c78282f80@redhat.com> <2026012648-vantage-mummified-2a43@gregkh> <2026012659-credit-suing-72ce@gregkh> <40fa8cab-af36-4420-9099-511474833fe1@redhat.com> Precedence: bulk X-Mailing-List: linux-serial@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: <40fa8cab-af36-4420-9099-511474833fe1@redhat.com> On Mon, Jan 26, 2026 at 11:49:45AM +0100, Jocelyn Falempe wrote: > On 26/01/2026 11:30, Greg Kroah-Hartman wrote: > > On Mon, Jan 26, 2026 at 11:20:21AM +0100, Greg Kroah-Hartman wrote: > > > On Mon, Jan 26, 2026 at 10:43:35AM +0100, Jocelyn Falempe wrote: > > > > On 26/01/2026 10:33, Greg Kroah-Hartman wrote: > > > > > On Mon, Jan 26, 2026 at 10:21:50AM +0100, Jocelyn Falempe wrote: > > > > > > This allows to build the kernel with CONFIG_VT enabled, and choose > > > > > > on the kernel command line to enable it or not. > > > > > > > > > > This says what is happening, but not why? > > > > > > > > > > > Add vt.enable=1 to force enable, or vt.enable=0 to force disable. > > > > > > > > > > Why are we using a 1990's technology for a new feature? What is this > > > > > going to allow to have happen? Who needs/wants this? Who will use it? > > > > > For what? > > > > > > > > The goal is to ease the transition to disable CONFIG_VT. > > > > > > > > So if this is merged, you can boot without VT on any Linux distribution, > > > > without rebuilding the kernel. > > > > > > But that's a distro-specific thing, the distro should be enabling or > > > disabling the option as it needs, it should not be a user-configurable > > > boot-time selection option as userspace depends entirely on this either > > > being there or not. Why would you have a kernel with both options but > > > userspace without that? > > > > And to follow-up on this, if a distro wanted to support this, why not > > just provide 2 different kernel images? One with this enabled and one > > without? It's up to the distro to support such a thing, not the kernel > > community, right? > > That's clearly not an option, they will prefer to keep VT enabled forever > than adding yet another kernel package. But that's a distro's choice to make, why are you forcing this onto the kernel? Either a distro wants to support a userspace with VT enabled, or not. So then choose the kernel option you wish to have here and away you go! > And for distributions that already have kernel and kernel-rt, that > means maintaining 4 kernels for all combination. Again, that's a distro choice, you are now forcing us to maintain the option due to the lack of an agreement in your organization :) thanks, greg k-h