From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (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 7AA902F2610; Wed, 19 Nov 2025 04:19:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763525986; cv=none; b=XJ+Upo0DtHFlgArJ2Nl2R9nlHe4Jeg1PKUtsxb5nh3Xf3QNSo20f85KwvKCMNuv2o0m88E9dPHIvGz5AT1rI22BPhrHJg4fDSWSSeAjY5hz86N7UbRxxMFkO0pcJpVLp8wSjLUIjoAFiBIPrabn5lUPaC93Ur4jLlA4IZkC8umw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763525986; c=relaxed/simple; bh=oMKI+mm6NvcX1Nhkehj2oI0t10jkBqILOytoJ0ie2aM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=gIRNbAYHvzNm7ESAqG1F8IQXtooNPleFzYUl+ylxcHCk+A2M2ztK6e44ntPOf8uUFZjKIun/4tWe7kO/0HfMDrz+FOuUPWmgcl5WuLmoDrhLXYu9Vs9eaTskDvIdxfx3RuMVch0ay3Tf6yL+7rPzOUaxQH2M7OFZJJhotX4iqr4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=ZkEyA49H; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="ZkEyA49H" Received: from pendragon.ideasonboard.com (unknown [205.220.129.225]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 47A3EDD9; Wed, 19 Nov 2025 05:17:33 +0100 (CET) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1763525855; bh=oMKI+mm6NvcX1Nhkehj2oI0t10jkBqILOytoJ0ie2aM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=ZkEyA49HzyQff15tgiyv30o02DpF05eCWgOFFeyRIftld88mZGWYFqvFfpq5tFiT7 qmh06MOv94SYitDIjq8gAMZipxjtWpXj/ASkTTm2DstrjCpcK/4iexQpDe7t9mvVEm /BixVLKPTXHGLQLjalm7JQInjWqsceOgxEB2V83c= Date: Wed, 19 Nov 2025 13:19:07 +0900 From: Laurent Pinchart To: Mauro Carvalho Chehab Cc: Ricardo Ribalda , Hans de Goede , Mauro Carvalho Chehab , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Greg Kroah-Hartman Subject: Re: [PATCH 4/4] media: uvcvideo: Introduce allow_privacy_override Message-ID: <20251119041907.GH10711@pendragon.ideasonboard.com> References: <20251117-uvcdynctrl-v1-0-aed70eadf3d8@chromium.org> <20251117-uvcdynctrl-v1-4-aed70eadf3d8@chromium.org> <2025111817-wages-anyone-e39a@gregkh> Precedence: bulk X-Mailing-List: linux-media@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: On Tue, Nov 18, 2025 at 03:09:16PM +0100, Mauro Carvalho Chehab wrote: > On Tue, Nov 18, 2025 at 06:14:09AM -0500, Greg Kroah-Hartman wrote: > > On Mon, Nov 17, 2025 at 08:14:19PM +0000, Ricardo Ribalda wrote: > > > Some camera modules have XU controls that can configure the behaviour of > > > the privacy LED. > > > > > > Block mapping of those controls, unless the module is configured with > > > a new parameter: allow_privacy_override. > > > > This is not the 1990's, please do not add new module parameters, they do > > not scale, nor work properly at all for modern hardware where you can > > have multiple devices in the same system. > > > > This isn't an agreement that we should do this feature at all, just that > > if you do, it should NOT be a module parameter. > > I agree with Greg: modprobe makes things harder specially on usb. > > Also, in the specific case of privacy leds, IMO it should never be > possible to directly disable it, not even root via a modprobe or > runtime parameter. > > Ok, as it might be some case where someone really wants to disable for his > special pet toy. If such cases are relevant, a Kconfig parameter could > be added (maybe depending on BROKEN), having privacy LED enabled by default. The feature was added by Logitech to their webcams to avoid the red privacy LED showing as a reflection on users' glasses. Whether or not users ended up caring, I don't know. The situation is different for webcams embedded in devices (even if they're internally UVC cameras), as the privacy LED is typically smaller and less bright in those devices. > This way, any sane distro-generated Kernel should always have the privacy > LED on when camera is in use. > > On other words, if someone has secure boot enabled, he can be more confident > that a distro-vendor signed Kernel will honour the privacy LED, and not > even the root can tamper with - as BIOS access to disable secure boot would > be needed to change it - plus, booting a non-signed kernel. -- Regards, Laurent Pinchart