linux-kernel - Re: [PATCH 6/6] eventfs: clean up dentry ops and add revalidate function

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20240131130039.241c8978@gandalf.local.home>
Date: Wed, 31 Jan 2024 13:00:39 -0500
From: Steven Rostedt <rostedt@...dmis.org>
To: Linus Torvalds <torvalds@...ux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@...nel.org>, linux-kernel@...r.kernel.org,
 linux-trace-kernel@...r.kernel.org
Subject: Re: [PATCH 6/6] eventfs: clean up dentry ops and add revalidate
 function

On Tue, 30 Jan 2024 11:03:55 -0800
Linus Torvalds <torvalds@...ux-foundation.org> wrote:

> It would probably be cleaner to make eventfs its own filesystem, or at
> least set its own dentry ops when looking up eventfs files.  But as it
> is, only eventfs dentries use d_fsdata, so we don't really need to split
> these things up by use.

BTW, I have been thinking about making eventfs a completely separate file
system that could be mounted outside of tracefs. One that is readonly that
only contains the "id" and "format" files and nothing more.

Why? Because perf and powertop both use those files to know how to parse
the raw event formats. I don't think there's anything in there that
requires root privileges to read. They should not be exposing any internal
kernel information besides the event format layouts, and it would be nice
to have a /sys/kernel/events directory that only had that.

Making eventfs a separate file system where, when added to tracefs, has the
control files for the specific trace_array, but for the /sys/kernel
directory, only cares about the trace format files.

Then tracefs could be nicely converted over to kernfs, and eventfs would be
its own entity.

-- Steve