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Date:   Wed, 14 Jun 2023 07:31:21 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Christian Brauner <brauner@kernel.org>
Cc:     Christoph Hellwig <hch@infradead.org>,
        Dmitry Vyukov <dvyukov@google.com>, Jan Kara <jack@suse.cz>,
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        linux-fsdevel@vger.kernel.org,
        syzkaller <syzkaller@googlegroups.com>
Subject: Re: [PATCH] block: Add config option to not allow writing to mounted
 devices
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On Wed, Jun 14, 2023 at 10:18:16AM +0200, Christian Brauner wrote:
> > I'm fine with a config option enforcing write blocking for any
> > BLK_OPEN_EXCL open.  Maybe the way to it is to:
> > 
> >  a) have an option to prevent any writes to exclusive openers, including
> >     a run-time version to enable it
> 
> I really would wish we don't make this runtime configurable. Build time
> and boot time yes but toggling it at runtime makes this already a lot
> less interesting.

With run time I really mean not compile time aka boot time.  Sorry for
not being precise.