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Date:   Wed, 14 Jun 2023 00:07:26 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Christian Brauner <brauner@kernel.org>
Cc:     Jan Kara <jack@suse.cz>, Colin Walters <walters@verbum.org>,
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        Theodore Ts'o <tytso@mit.edu>, yebin <yebin@huaweicloud.com>,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH] block: Add config option to not allow writing to mounted
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On Wed, Jun 14, 2023 at 09:05:41AM +0200, Christian Brauner wrote:
> > I kind of like the flexibility of device cgroups but it does not seem to
> 
> Let's not bring in device cgroups here just yet. They're an optional LSM
> security measure while your change is more fundamental which is the
> right thing to do imho.

Yes.  That last thing we need is hiding fundamentally security tradeoffs
in weird optional corners of the kernel.