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Subject: Re: [RFC PATCH] rootfs: force mounting rootfs as tmpfs
From:   Mimi Zohar <zohar@linux.vnet.ibm.com>
To:     Arvind Sankar <nivedita@alum.mit.edu>,
        Rob Landley <rob@landley.net>
Cc:     initramfs <initramfs@vger.kernel.org>,
        Taras Kondratiuk <takondra@cisco.com>,
        Victor Kamensky <kamensky@cisco.com>,
        linux-security-module <linux-security-module@vger.kernel.org>,
        Al Viro <viro@ZenIV.linux.org.uk>,
        linux-kernel <linux-kernel@vger.kernel.org>
Date:   Wed, 31 Jan 2018 23:22:01 -0500
In-Reply-To: <20180201020331.GA3774@rani.riverdale>
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         <1517436423.3469.237.camel@linux.vnet.ibm.com>
         <a538e55c-81ca-6d59-20cf-21b47387c3e2@landley.net>
         <20180201020331.GA3774@rani.riverdale>
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On Wed, 2018-01-31 at 21:03 -0500, Arvind Sankar wrote:
> On Wed, Jan 31, 2018 at 05:48:20PM -0600, Rob Landley wrote:
> > On 01/31/2018 04:07 PM, Mimi Zohar wrote:
> > > On Wed, 2018-01-31 at 13:32 -0600, Rob Landley wrote:>> (The old "I configured in tmpfs and am using rootfs but I want that
> > rootfs
> > >> to be ramfs, not tmpfs" code doesn't seem to be a real-world concern, does
> > >> it?)
> > > 
> > > I must be missing something.  Which systems don't specify "root=" on
> > > the boot command line.
> > 
> > Any system using initrd or initramfs?
> > 
> 
> Don't a lot of initramfs setups use root= to tell the initramfs which
> actual root file system to switch to after early boot?

With your patch and specifying "root=tmpfs", dracut is complaining:

dracut: FATAL: Don't know how to handle 'root=tmpfs'
dracut: refusing to continue

Mimi