Re: [PATCH 3/3] fs: add immutable rootfs

[Gao Xiang <hsiangkao@linux.alibaba.com>]

On 2026/1/7 10:47, Al Viro wrote:
> On Wed, Jan 07, 2026 at 10:28:23AM +0800, Gao Xiang wrote:
> 
>> Just one random suggestion.  Regardless of Al's comments,
>> if we really would like to expose a new visible type to
>> userspace,   how about giving it a meaningful name like
>> emptyfs or nullfs (I know it could have other meanings
>> in other OSes) from its tree hierarchy to avoid the
>> ambiguous "rootfs" naming, especially if it may be
>> considered for mounting by users in future potential use
>> cases?
> 
> *boggle*
> 
> _what_ potential use cases?  "This here directory is empty and
> it'll stay empty and anyone trying to create stuff in it will
> get an error; oh, and we want it to be a mount boundary, for
> some reason"?
> 
> IDGI...

My concern is that "rootfs" naming is already (ab)used in various
ways, although kernel folks know what happens here by checking
the kernel code for example, but making it visible to users I'm
afraid that userspace folks already get various concepts out of
the word "root" (it's absolutely not "chroot" but for a mount
namespace?).

Thanks,
Gao Xiang