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([2a01:e0a:c:37e0:8998:e0cf:68cc:1b62]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-4804d84589bsm273181895e9.3.2026.01.26.04.26.37 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 26 Jan 2026 04:26:37 -0800 (PST) Message-ID: <99371939-e9b2-4114-8e27-e605ebf941de@redhat.com> Date: Mon, 26 Jan 2026 13:26:34 +0100 Precedence: bulk X-Mailing-List: linux-serial@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH] vt: Add enable module parameter To: Greg Kroah-Hartman Cc: Jiri Slaby , Nicolas Pitre , Calixte Pernot , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org References: <20260126092234.713465-1-jfalempe@redhat.com> <2026012613-cotton-jellied-b67a@gregkh> <48be84fb-bee4-4a22-bde4-0d0c78282f80@redhat.com> <2026012648-vantage-mummified-2a43@gregkh> <45526d98-57b6-456e-babc-61b7331318c0@redhat.com> <2026012642-threefold-atypical-a3ad@gregkh> From: Jocelyn Falempe In-Reply-To: <2026012642-threefold-atypical-a3ad@gregkh> X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: pCgaR1w8ODpHd89qFBIUhTUwm1QN7UXzl2envY0puJs_1769430399 X-Mimecast-Originator: redhat.com Content-Language: en-US, fr Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 26/01/2026 11:59, Greg Kroah-Hartman wrote: > On Mon, Jan 26, 2026 at 11:48:50AM +0100, Jocelyn Falempe wrote: >> On 26/01/2026 11:20, 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? >> >> Actually the userspace side works with or without VT, at least with Fedora, >> I've my Gnome session in both cases. > > Great! Then why is this even needed? Who wants such a "let's not make > up our mind until we boot" type of system? > > Given that traditionally the command line is a "secure" thing, that is > locked down by distros and orginizations, who would ever be able to be > changing this type of thing? Who would want to support userspace that > handles both at the same time? > > I don't see the issue here, if a distro doesn't want to support VT, then > disable it in the kernel and all is good. If they do want to support > it, than enable it. Don't do both :) Maybe the real issue is that VT cannot be built as a module. That way the userspace would be able to load it only if it needs it. That's probably more complex than my 3 lines patch, but I can try. Would you prefer it that way? > > thanks, > > greg k-h >