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From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Wed, 3 Jan 2024 14:17:22 -0800
Message-ID: <CAHk-=wgHEyd2z-KvaV6ndKSqGjkisE0MBEXsFkkxeicHTUy-Xg@mail.gmail.com>
Subject: Re: [PATCH] eventfs: Stop using dcache_readdir() for getdents()
To: Al Viro <viro@zeniv.linux.org.uk>
Cc: Steven Rostedt <rostedt@goodmis.org>, LKML <linux-kernel@vger.kernel.org>, 
	Linux Trace Kernel <linux-trace-kernel@vger.kernel.org>, Masami Hiramatsu <mhiramat@kernel.org>, 
	Mathieu Desnoyers <mathieu.desnoyers@efficios.com>, Christian Brauner <brauner@kernel.org>, 
	linux-fsdevel@vger.kernel.org, 
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Content-Type: text/plain; charset="UTF-8"

On Wed, 3 Jan 2024 at 14:14, Al Viro <viro@zeniv.linux.org.uk> wrote:
>
> On Wed, Jan 03, 2024 at 01:54:36PM -0800, Linus Torvalds wrote:
>
> > Again: UNTESTED, and meant as a "this is another way to avoid messing
> > with the dentry tree manually, and just using the VFS interfaces we
> > already have"
>
> That would break chown(), though.

Right,. That's why I had that note about

   So take this as a "this might work", but it probably needs a bit more
   work - eventfs_set_attr() should set some bit in the inode to say
   "these have been set manually", and then revalidate would say "I'll
   not touch inodes that have that bit set".

and how my example patch overrides things a bit *too* aggressively.

That said, I think the patch that Steven just sent out is the right
direction to go regardless. The d_revalidate() thing was literally
just a "we can do this many different ways".

                     Linus