block2mtd driver won't take kernel command-line parameters

block2mtd driver won't take kernel command-line parameters

[Ryan B. Lynch]

(I mentioned this to Jorn directly on Friday, but he seems to be busy
with some other stuff at the moment, so I thought I'd send it to the
list in general.)

When the "block2mtd" driver is built into the kernel, it's possible to
add new block devices as emulated MTDs with a command like:

    echo "/dev/hda2" > /sys/module/block2mtd/parameters/block2mtd

(which would create new /dev/mtd* and /dev/mtdblock* devices).  In order
to make the device appear at boot time, Jorn has told me that you can
provide the same parameter to the kernel on the boot command line, like so:

    block2mtd.block2mtd=/dev/hda2

I'm using the line

    append="block2mtd.block2mtd=/dev/hda2"

in the file "/etc/lilo.conf" in to try to pass that parameter.

BUT... it doesn't seem to work.  I can set the block2mtd device up after
booting, using the "echo..." method above, without any errors or other
problems.  Adding the kernel command-line parameter seems to have no
effect at all--there are no error messages in 'dmesg', or anything like
that.  'cat /proc/cmdline' shows the parameter as it should be, so I
know that parameter is getting passed to the kernel.

I tried passing a few SCSI- and USB-related parameters at the command
line, too, just to make sure that parameter handling in general was
working properly.  Everything worked fine, just like it's supposed to.

Has anyone else encountered similar issues making block2mtd work with
command-line parameters?  Am I doing something stupid in my LILO config
line, or what?  Any ideas or help are appreciated, because I'm at a dead
end, not knowing enough about the kernel code to go much further on my own.

For the record, I'm using kernel version 2.6.12, with the MTD patches
from CVS of 2005.08.14.  I can provide configs on request.

-Ryan

Re: block2mtd driver won't take kernel command-line parameters

[Jörn Engel]

On Mon, 22 August 2005 20:03:42 +0000, Ryan B. Lynch wrote:
> 
> (I mentioned this to Jorn directly on Friday, but he seems to be busy
> with some other stuff at the moment, so I thought I'd send it to the
> list in general.)

Yup.  I started the removal stuff over the weekend, btw.  It quickly
turned out that a full mtd class in sysfs is needed and I will do that
first, then add the block2mtd bits.  Quite a bit of work, I'm afraid.

> When the "block2mtd" driver is built into the kernel, it's possible to
> add new block devices as emulated MTDs with a command like:
> 
>     echo "/dev/hda2" > /sys/module/block2mtd/parameters/block2mtd
> 
> (which would create new /dev/mtd* and /dev/mtdblock* devices).  In order
> to make the device appear at boot time, Jorn has told me that you can
> provide the same parameter to the kernel on the boot command line, like so:
> 
>     block2mtd.block2mtd=/dev/hda2
> 
> I'm using the line
> 
>     append="block2mtd.block2mtd=/dev/hda2"
> 
> in the file "/etc/lilo.conf" in to try to pass that parameter.
> 
> BUT... it doesn't seem to work.  I can set the block2mtd device up after
> booting, using the "echo..." method above, without any errors or other
> problems.  Adding the kernel command-line parameter seems to have no
> effect at all--there are no error messages in 'dmesg', or anything like
> that.  'cat /proc/cmdline' shows the parameter as it should be, so I
> know that parameter is getting passed to the kernel.
> 
> I tried passing a few SCSI- and USB-related parameters at the command
> line, too, just to make sure that parameter handling in general was
> working properly.  Everything worked fine, just like it's supposed to.
> 
> Has anyone else encountered similar issues making block2mtd work with
> command-line parameters?  Am I doing something stupid in my LILO config
> line, or what?  Any ideas or help are appreciated, because I'm at a dead
> end, not knowing enough about the kernel code to go much further on my own.
> 
> For the record, I'm using kernel version 2.6.12, with the MTD patches
> from CVS of 2005.08.14.  I can provide configs on request.

Would be nice if someone else takes a look.  I won't find time before
the weekend, I'm afraid.  And even then, it could be less than I would
like.

Jörn

-- 
To my face you have the audacity to advise me to become a thief - the worst
kind of thief that is conceivable, a thief of spiritual things, a thief of
ideas! It is insufferable, intolerable!
-- M. Binet in Scarabouche