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 9D1A230DD0D for ; Wed, 3 Sep 2025 13:51:46 +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=1756907508; cv=none; b=m+aqPURvnFsM+9hlWUnqiJlgWa+9OF6XDRf9oO1f12WnJEb77pynLVTtImW37+YTT112Pb0Q1uUsGIrajEhg+NmeD/ugMXpHpffpGO0SfDbiFOdCSHpWxX/nCaEQgbQwHYK9E4HqgFudES/pCfuNCnXNBW+QyjzVQHy9wWQUYSs= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1756907508; c=relaxed/simple; bh=O/fRfb9etV3ZNsMPi8FLLFmn+EVAdVXV9qldkPSBP9Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=b8tCW/RVAxlGskkjaQkOUYZ/Wy0cTAFcz53qFP2+Hvg6QOg+gs2tKLBZwxSGVE0SsGAl7Gc+5mUoX4fK4IYSI5boHrilm9xIzlfIep09DGclPpne5uGLI9vSWeNQYez+rDjuQyue+5EZL93fbm2V1MLwg+xyLHRawCkOd/n9DKA= 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=Rvhzm2b+; 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="Rvhzm2b+" Received: from pendragon.ideasonboard.com (230.215-178-91.adsl-dyn.isp.belgacom.be [91.178.215.230]) by perceval.ideasonboard.com (Postfix) with UTF8SMTPSA id 51444842; Wed, 3 Sep 2025 15:50:36 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1756907436; bh=O/fRfb9etV3ZNsMPi8FLLFmn+EVAdVXV9qldkPSBP9Y=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Rvhzm2b+1KMYIucIfgcqj4LASB0TfE7eM4wlyzQA3B5QFm5Vp6DfXzqzwSEd1J156 fHqb1JhcKRbQBbR60tZPSPtqvNVXvbkiby8x6yA2xuzO7ebhl28xADjumQM/CAkwHo Mxylh90qfSrTxGrGx9qZ4vdaXwW2XkevIVRyNJgE= Date: Wed, 3 Sep 2025 15:51:24 +0200 From: Laurent Pinchart To: Mauro Carvalho Chehab Cc: Johannes Berg , Jonathan Corbet , Randy Dunlap , Jani Nikula , Vegard Nossum , ksummit@lists.linux.dev, Linux Documentation , Akira Yokosawa , Bagas Sanjaya , Matthew Wilcox Subject: Re: [TECH TOPIC] Kernel documentation - update and future directions Message-ID: <20250903135124.GG3648@pendragon.ideasonboard.com> References: <20250902141434.3e5b14e4@foz.lan> <8339a5dd-446d-4717-9d68-983f5e2354b3@sirena.org.uk> <87ecsox4uy.fsf@trenco.lwn.net> <20250902191929.504977bf@foz.lan> <87frd4vfys.fsf@trenco.lwn.net> <20250903124229.332dfeae@foz.lan> <431ce4a26d70de6b6d63778e62b732dc035633f9.camel@sipsolutions.net> <20250903153905.7d93c693@foz.lan> Precedence: bulk X-Mailing-List: ksummit@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20250903153905.7d93c693@foz.lan> On Wed, Sep 03, 2025 at 03:39:05PM +0200, Mauro Carvalho Chehab wrote: > Em Wed, 03 Sep 2025 12:45:25 +0200 Johannes Berg escreveu: > > On Wed, 2025-09-03 at 12:42 +0200, Mauro Carvalho Chehab wrote: > > > > For example, use case we have: using nix-shell to lock down the software > > > > used to build, for reproducible builds and similar reasons. Without -- > > > > pure, PATH may still contain (last!) software from the system itself, > > > > but it should basically never be used. > > > > > > if the PATH is mangled, you'll have a lot more problems than just > > > building docs as it will pick wrong exec files anyway. > > > > Err, no? To search a binary, directories in $PATH are meant to be > > searched in order of appearance. It's well-defined which one you pick > > for which, and this setup takes advantage of that (with a rather long > > $PATH) to control the binaries used for the build. > > Yes. So? the logic does that. > > > > In the particular case of docs, if you have, for instance, two different > > > python versions, one with sphinx and another one without it, it may pick > > > the wrong one, causing the build to fail. There's nothing the build system > > > can do to solve it. The proper fix would be to wrap the calling logic > > > to save the env before running under nix-shell, restoring env afterwards. > > > > I don't follow. If this setup breaks the build then that's good, I'll > > fix the env. If the build does magic inside and sort of ignores $PATH, > > that's bad. > > The build logic does follow PATH. If python --version < 3.7, it will > seek, within PATH, for python > 3.6. Please, let's stop here. As pointed out by Jani, Johannes and Jon, that's not a good idea. If the user wants to shoot themselves in the foot, that's all fine. Printing a message to indicate they may want to use a more recent Python version is totally fine. Picking a Python interpreter manually to override the python3 symlink is not fine. -- Regards, Laurent Pinchart