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Date: Thu, 24 Jul 2025 09:36:52 +0200
From: Christian Brauner <brauner@kernel.org>
To: Aleksa Sarai <cyphar@cyphar.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>, Jan Kara <jack@suse.cz>, 
	Jonathan Corbet <corbet@lwn.net>, Shuah Khan <shuah@kernel.org>, linux-kernel@vger.kernel.org, 
	linux-fsdevel@vger.kernel.org, linux-api@vger.kernel.org, linux-doc@vger.kernel.org, 
	linux-kselftest@vger.kernel.org
Subject: Re: [PATCH RFC v2 0/4] procfs: make reference pidns more user-visible
Message-ID: <20250724-bekunden-einplanen-160f57e944e9@brauner>
References: <20250723-procfs-pidns-api-v2-0-621e7edd8e40@cyphar.com>
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In-Reply-To: <20250723-procfs-pidns-api-v2-0-621e7edd8e40@cyphar.com>

On Wed, Jul 23, 2025 at 09:18:50AM +1000, Aleksa Sarai wrote:
> Ever since the introduction of pid namespaces, procfs has had very
> implicit behaviour surrounding them (the pidns used by a procfs mount is
> auto-selected based on the mounting process's active pidns, and the
> pidns itself is basically hidden once the mount has been constructed).
> 
> /* pidns mount option for procfs */

I like it. I think this will be very useful!
Fwiw, I think sysfs could probably use the same treatment.
It should probably gain a pidns & netns mount option and the ioctls to
get those out of sysfs so you know where that sysfs belongs. Thoughts?