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	Sat, 24 Jan 2026 20:28:40 +0000
Date: Sat, 24 Jan 2026 20:28:40 +0000
From: Al Viro <viro@zeniv.linux.org.uk>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-fsdevel@vger.kernel.org, Christian Brauner <brauner@kernel.org>,
	Jan Kara <jack@suse.cz>, Nikolay Borisov <nik.borisov@suse.com>,
	Max Kellermann <max.kellermann@ionos.com>
Subject: Re: [PATCH][RFC] get rid of busy-wait in shrink_dcache_tree()
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Sat, Jan 24, 2026 at 11:32:59AM -0800, Linus Torvalds wrote:
> On Sat, 24 Jan 2026 at 10:41, Al Viro <viro@zeniv.linux.org.uk> wrote:
> >
> > > In fact, RANDSTRUCT is so broken in general that we actually taint the
> > > kernel if you enable that crazy option in the first place. So no,
> > > "what if somebody enables it on random things" is not even remotely
> > > worth worrying about.
> >
> > Very much agreed, but we *do* have that on e.g. struct path (two pointers),
> > as well as struct inode, struct file, struct mount, etc.  As far as VFS goes,
> > those are core data structures...
> 
> I certainly wouldn't mind if we remove the 'struct path' one in
> particular. It's insanely pointless to do randstruct on two fields.

<wry>
Frankly, each time I talk to these folks I keep hearing "Every bit
is wanted/Every bit is good/Every bit is needed/In your neighborhood"
set to the obvious tune...
</wry>