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    SubjectRe: No /dev/root with devtmpfs?
    On Mon, Feb 13, 2012 at 19:48, H. Peter Anvin <> wrote:
    > On 02/13/2012 12:25 AM, Kirill Smelkov wrote:
    >>> The bootloader might pass the root partition to the kernel via the
    >>> "root=" kernel parameter; these can be read at /proc/cmdline.
    >>> For example, on an HP iPAQ hx4700: root=/dev/mtdblock2
    >> This does not work universally either, for example for
    >>     root=PARTUUID=00112233-4455-6677-8899-AABBCCDDEEFF
    >> the kernel scans partitions and finds one for root by partition uuid
    >> (see name_to_dev_t() in init/do_mounts.c).
    >> That's exactly my situation - I have universal flash image which can
    >> bee booted via CF slot (on several boards, thus will have different
    >> /dev/hd? or /dev/sd?) and via usb/cardreader (again different /dev/
    >> entry), and root is mounted by partition id.
    >> The kernel has no problem finding root partition and mounting it. I just
    >> needed a sane and robust way to know its choice.
    > In this case it's not the kernel, but the initramfs which does this
    > lookup.

    root=PARTUUID= is in-kernel mount GTP support, which works without an initramfs.

    > In that case the initramfs could/should create /dev/root.

    We dropped all that in initramfs for the earlier in this thread
    mentioned reasons.

    /dev/root is not what we want, or what tools should expect to be there
    today; it will not work with modern filesystems, which have no
    single-device relationship.

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      Last update: 2012-02-13 20:33    [W:0.024 / U:75.964 seconds]
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