From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mimi Zohar Subject: Re: [RFC PATCH] rootfs: force mounting rootfs as tmpfs Date: Thu, 01 Feb 2018 16:51:52 -0500 Message-ID: <1517521912.3619.0.camel@linux.vnet.ibm.com> References: <1517348777.3469.5.camel@linux.vnet.ibm.com> <1814af5c-170d-39c0-58fd-02eb7216e008@landley.net> <1517436423.3469.237.camel@linux.vnet.ibm.com> <20180201020331.GA3774@rani.riverdale> <1517458921.3329.2.camel@linux.vnet.ibm.com> <1517500500.3974.45.camel@linux.vnet.ibm.com> <875e5d2d-9ffe-14ab-090a-4a9632af0f35@landley.net> Mime-Version: 1.0 Content-Transfer-Encoding: quoted-printable Return-path: In-Reply-To: <875e5d2d-9ffe-14ab-090a-4a9632af0f35-VoJi6FS/r0vR7s880joybQ@public.gmane.org> Sender: initramfs-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="iso-8859-1" To: Rob Landley , Arvind Sankar Cc: initramfs , Taras Kondratiuk , Victor Kamensky , linux-security-module , Al Viro , linux-kernel On Thu, 2018-02-01 at 11:09 -0600, Rob Landley wrote: > On 02/01/2018 09:55 AM, Mimi Zohar wrote: > > On Thu, 2018-02-01 at 09:20 -0600, Rob Landley wrote: > >=20 > >>> With your patch and specifying "root=3Dtmpfs", dracut is complaining: > >>> > >>> dracut: FATAL: Don't know how to handle 'root=3Dtmpfs' > >>> dracut: refusing to continue > >> > >> [googles]... I do not understand why this package exists. > >> > >> If you're switching to another root filesystem, using a tool that > >> wikipedia[citation needed] says has no purpose but to switch to another > >> root filesystem, (so let's reproduce the kernel infrastructure in > >> userspace while leaving it the kernel too)... why do you need initramfs > >> to be tmpfs? You're using it for half a second, then discarding it, > >> what's the point of it being tmpfs? > >=20 > > Unlike the kernel image which is signed by the distros, the initramfs > > doesn't come signed, because it is built on the target system. =C2=A0Ev= en > > if the initramfs did come signed, it is beneficial to measure and > > appraise the individual files in the initramfs. >=20 > You can still shoot yourself in the foot with tmpfs. People mount a /run > and a /tmp and then as a normal user you can go > https://twitter.com/landley/status/959103235305951233 and maybe the > default should be a little more clever there... >=20 > I'll throw it on the todo heap. :) >=20 > >> Sigh. If people are ok with having rootfs just be tmpfs whenever tmpfs > >> is configured in, even when you're then going to overmount it with > >> something else like you're doing, let's just _remove_ the test. If it > >> can be tmpfs, have it be tmpfs. > >=20 > > Very much appreciated! >=20 > Not yet tested, but something like the attached? (Sorry for the > half-finished doc changes in there, I'm at work and have a 5 minute > break. I can test properly this evening if you don't get to it...) Yes, rootfs is being mounted as tmpfs. Mimi