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From: Jonathan Corbet <corbet@lwn.net>
To: Christian Brauner <brauner@kernel.org>
Cc: Miklos Szeredi <mszeredi@redhat.com>, linux-fsdevel@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-api@vger.kernel.org,
 linux-man@vger.kernel.org, linux-security-module@vger.kernel.org, Karel
 Zak <kzak@redhat.com>, Ian Kent <raven@themaw.net>, David Howells
 <dhowells@redhat.com>, Linus Torvalds <torvalds@linux-foundation.org>, Al
 Viro <viro@zeniv.linux.org.uk>, Christian Brauner <christian@brauner.io>,
 Amir Goldstein <amir73il@gmail.com>, Matthew House
 <mattlloydhouse@gmail.com>, Florian Weimer <fweimer@redhat.com>, Arnd
 Bergmann <arnd@arndb.de>
Subject: Re: [PATCH v4 5/6] add listmount(2) syscall
In-Reply-To: <20231108-redakteur-zuschauen-a9aeafaf4fad@brauner>
References: <20231025140205.3586473-1-mszeredi@redhat.com>
 <20231025140205.3586473-6-mszeredi@redhat.com>
 <87il6d1cmu.fsf@meer.lwn.net>
 <20231108-redakteur-zuschauen-a9aeafaf4fad@brauner>
Date: Wed, 08 Nov 2023 09:20:28 -0700
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Christian Brauner <brauner@kernel.org> writes:

>> Why use struct __mount_arg (or struct mnt_id_req :) here rather than
>> just passing in the mount ID directly?  You don't use the request_mask
>
> Please see Arnd's detailed summary here:
> https://lore.kernel.org/lkml/44631c05-6b8a-42dc-b37e-df6776baa5d4@app.fastmail.com

Ah, makes sense, I'd missed that.

Given this, though, it seems like maybe sys_listmount() should enforce
that req->request_mask==0 ?

Thanks,

jon