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Date: Wed, 19 Nov 2025 10:03:36 +0100
From: Christoph Hellwig <hch@lst.de>
To: Christian Brauner <brauner@kernel.org>
Cc: viro@zeniv.linux.org.uk, jack@suse.cz, linux-fsdevel@vger.kernel.org,
	Nathan Chancellor <nathan@kernel.org>,
	Nicolas Schier <nicolas.schier@linux.dev>,
	linux-kbuild@vger.kernel.org
Subject: Re: [PATCH] fs: unexport ioctl_getflags
Message-ID: <20251119090336.GC24598@lst.de>
References: <20251118070941.2368011-1-hch@lst.de> <20251119-frist-vertragen-22e1d099b118@brauner>
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On Wed, Nov 19, 2025 at 09:45:46AM +0100, Christian Brauner wrote:
> On Tue, Nov 18, 2025 at 08:09:41AM +0100, Christoph Hellwig wrote:
> > No modular users, nor should there be any for a dispatcher like this.
> > 
> > Signed-off-by: Christoph Hellwig <hch@lst.de>
> > ---
> 
> Ideally we'd be able to catch unnecessary exports automatically.
> Which would also be nice because it would mean that we could enforce
> automatic removal of unused exports. I'm pretty sure we have a bunch of
> them without realizing it.

The problem with that is that it is so configuration dependent.

Also there are occasional cases where we add exports in one merge window
for the users to appear in the next one to reduce cross-subsystem
dependencies, so we'd nee to do this manually.

Maybe just having CONFIG_TRIM_UNUSED_KSYMS outout the unused symbols
in a log file and manually looking over that for various allmodconfigs
might be a good start.