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Date: Thu, 15 May 2025 12:10:43 +0200
From: Christian Brauner <brauner@kernel.org>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: Allison Karlitskaya <allison.karlitskaya@redhat.com>, 
	linux-fsdevel@vger.kernel.org, lis@redhat.com
Subject: Re: [PATCH] fuse: add max_stack_depth to fuse_init_in
Message-ID: <20250515-dunkel-rochen-ad18a3423840@brauner>
References: <CAJfpegtdy7BYUpt795vGKFDHfRpyPVhqrL=gbQzauTvNawrZyw@mail.gmail.com>
 <20250514121415.2116216-1-allison.karlitskaya@redhat.com>
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On Thu, May 15, 2025 at 10:42:30AM +0200, Miklos Szeredi wrote:
> On Wed, 14 May 2025 at 14:14, Allison Karlitskaya
> <allison.karlitskaya@redhat.com> wrote:
> > Use one of the unused fields in fuse_init_in to add a max_stack_depth
> > uint32_t (matching the max_stack_depth uint32_t in fuse_init_out).
> 
> This is not a fuse-only thing.
> 
> What about making it a read-only sysctl attribute? E.g.
> /proc/sys/fs/max-stack-depth.

Before making this a kernel wide sysctl attribute we should have actual
users that need more than two right now. IIUC, then making this an
attribute in FUSE will happen at some point anyway. For example, if
userspace wants to have a FUSE specific stacking limit that's different
from the global limit.