linux-kernel - Re: [PATCH] use tmpfs for rootfs v3

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-ID: <8bd0f97a0810221203k1adaeec8xe4c47295dc823264@mail.gmail.com>
Date:	Wed, 22 Oct 2008 15:03:35 -0400
From:	"Mike Frysinger" <vapier.adi@...il.com>
To:	"Bodo Eggert" <7eggert@....de>
Cc:	jeffschroeder@...puter.org,
	"Geert Uytterhoeven" <geert@...ux-m68k.org>,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH] use tmpfs for rootfs v3

On Mon, Oct 20, 2008 at 14:13, Bodo Eggert wrote:
> On Sun, 19 Oct 2008, Mike Frysinger wrote:
>> On Fri, Oct 17, 2008 at 07:16, Bodo Eggert wrote:
>> > --- linux-2.6.27.2-numlock/fs/Kconfig   2008-10-10 13:18:34.000000000 +0200
>> > +++ linux-2.6.27.3-tmpfs/fs/Kconfig     2008-10-11 15:42:21.000000000 +0200
>> > @@ -953,6 +953,27 @@ config TMPFS_POSIX_ACL
>> >
>> >          If you don't know what Access Control Lists are, say N.
>> >
>> > +config TMPFS_ROOT
>> > +       bool "Use tmpfs instrad of ramfs for initramfs"
>> > +       depends on TMPFS && SHMEM
>> > +       default n
>> > +       help
>> > +         This replaces the ramfs used for unpacking the cpio images
>> > +         with tmpfs.
>> > +
>> > +         If unsure, say N
>>
>> this should be init/Kconfig and depend on BLK_DEV_INITRD i think.  and
>> then update the comment to talk about the initial filesystem rather
>> than cpio images.
>
> Maybe, but then you'd have to go to filesystems->pseudo-fs to enable tmpfs,
> then to i-don't-remember to set it as the rootfs, and then back to
> fs->pseudo-fs to unselect ramfs.
>
> Thinking of it as a tmpfs option makes it much easier to use.

i guess that works

>> > +config RAMFS
>> > +       bool "Ramfs file system support" if TMPFS_ROOT
>>
>> if you have initramfs support disabled, then you should be able to
>> disable RAMFS as well.  so perhaps the depend should read like:
>> if BLK_DEV_INITRD && TMPFS_ROOT || !BLK_DEV_INITRD
>
> No, since a kernel not having initcpio support will mount rootfs anyway,

we should get that fixed then

> create some directories and special files and use them to open the console
> and to mount the real root into.

erm, i dont recall seeing any init code create any directories or
files.  opening /dev/console doesnt require the fake rootfs, nor does
mounting the real root on top of it.  where exactly do you see this
logic ?
-mike
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/