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Date: Fri, 26 Jan 2024 17:08:57 -0500
From: Steven Rostedt <rostedt@goodmis.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
CC: LKML <linux-kernel@vger.kernel.org>,
 Linux Trace Devel <linux-trace-devel@vger.kernel.org>,
 Masami Hiramatsu <mhiramat@kernel.org>,
 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>,
 Christian Brauner <brauner@kernel.org>, Ajay Kaher <ajay.kaher@broadcom.com>,
 Geert Uytterhoeven <geert@linux-m68k.org>,
 linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH] eventfs: Have inodes have unique inode numbers
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On January 26, 2024 4:49:13 PM EST, Linus Torvalds <torvalds@linux-foundat=
ion=2Eorg> wrote:
>On Fri, 26 Jan 2024 at 13:36, Linus Torvalds
><torvalds@linux-foundation=2Eorg> wrote:
>>
>> If you have more than 4 billion inodes, something is really really wron=
g=2E
>
>Btw, once again, the vfs layer function you took this from *does* have
>some reason to worry=2E Somebody might be doing 'pipe()' in a loop=2E
>
>Also, if your worry is "what if somebody mounts that thing a million
>times", the solution to *that* would have been to make it a per-sb
>counter, which I think would be cleaner anyway=2E
>

I'm more worried about a loop of:

cd /sys/kernel/tracing/instances
while:; do mkdir foo ; rmdir foo: done

Which is what my tests do=2E And I have run that for over a weekend=2E


>But my real issue is that I think you would be *much* better off just
>deleting code, instead of adding new code=2E
>
>For example, what purpose does 'e->dentry' and 'ei->d_childen[]' have?
>Isn't that entirely a left-over from the bad old days?
>

I'm not at my computer, but when I tried deleting that, it caused issues w=
ith the lookup code=2E

-- Steve=20

>So please try to look at things to *fix* and simplify, not at things
>to mess around with and make more complicated=2E
>
>              Linus