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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Fri, 26 Jan 2024 14:29:01 -0800
Message-ID: <CAHk-=whAG6TM6PgH0YnsRe6U=RzL+JMvCi=_f0Bhw+q_7SSZuw@mail.gmail.com>
Subject: Re: [PATCH] eventfs: Have inodes have unique inode numbers
To: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>, 
	Linux Trace Devel <linux-trace-devel@vger.kernel.org>, Masami Hiramatsu <mhiramat@kernel.org>, 
	Christian Brauner <brauner@kernel.org>, Ajay Kaher <ajay.kaher@broadcom.com>, 
	Geert Uytterhoeven <geert@linux-m68k.org>, linux-fsdevel <linux-fsdevel@vger.kernel.org>
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On Fri, 26 Jan 2024 at 14:14, Mathieu Desnoyers
<mathieu.desnoyers@efficios.com> wrote:
>
> I do however have a concern with the approach of using the same
> inode number for various files on the same filesystem: AFAIU it
> breaks userspace ABI expectations.

Virtual filesystems have always done that in various ways.

Look at the whole discussion about the size of the file. Then look at /proc.

And honestly, eventfs needs to be simplified. It's a mess. It's less
of a mess than it used to be, but people should *NOT* think that it's
a real filesystem.

Don't use some POSIX standard as an expectation for things like /proc,
/sys or tracefs.

              Linus