[2.6.24-rc5-mm1] Why CONFIG_BLK_DEV_RAM=m makes \"#ifdef CONFIG_BLK_DEV_RAM\" false?

[2.6.24-rc5-mm1] Why CONFIG_BLK_DEV_RAM=m makes \"#ifdef CONFIG_BLK_DEV_RAM\" false?

[Tetsuo Handa]

Hello.

I found that

 CONFIG_BLK_DEV_RAM=m

in my .config makes

 #ifdef CONFIG_BLK_DEV_RAM

false.

I guess something is wrong with .config parsing.

Regards.

Re: [2.6.24-rc5-mm1] Why CONFIG_BLK_DEV_RAM=m makes \"#ifdef CONFIG_BLK_DEV_RAM\" false?

[Randy Dunlap]

On Fri, 14 Dec 2007 14:04:19 +0900 Tetsuo Handa wrote:

> Hello.
> 
> I found that
> 
>  CONFIG_BLK_DEV_RAM=m
> 
> in my .config makes
> 
>  #ifdef CONFIG_BLK_DEV_RAM
> 
> false.
> 
> I guess something is wrong with .config parsing.

Look at include/linux/autoconf.h.  You should see a line like:

#define CONFIG_BLK_DEV_RAM_MODULE 1

if CONFIG_BLK_DEV_RAM=m

or like:

#define CONFIG_BLK_DEV_RAM 1

if CONFIG_BLK_DEV_RAM=y.


I don't think that this is a change from the recent past.

---
~Randy

Re: [2.6.24-rc5-mm1] Why CONFIG_BLK_DEV_RAM=m makes \\\"#ifdef CONFIG_BLK_DEV_RAM\\\" false?

[Tetsuo Handa]

Hello.

Randy Dunlap <randy.dunlap@oracle.com> wrote:
> I don't think that this is a change from the recent past.

Oh, it is my mistake.

I found that choosing CONFIG_BLK_DEV_RAM=m makes
impossible to pass an initrd image since
populate_rootfs() in init/initramfs.c omits
code for checking whether the image is an initrd or not.
But I didn't know CONFIG_BLK_DEV_RAM is tristate.
So, I have to change to CONFIG_BLK_DEV_RAM=y when
I want to pass an initrd image after "make allmodconfig".

Thank you.

Re: [2.6.24-rc5-mm1] Why CONFIG_BLK_DEV_RAM=m makes \\\"#ifdef CONFIG_BLK_DEV_RAM\\\" false?

[Jan Engelhardt]

On Dec 14 2007 15:15, Tetsuo Handa wrote:
>Hello.
>
>Randy Dunlap <randy.dunlap@oracle.com> wrote:
>> I don't think that this is a change from the recent past.
>
>Oh, it is my mistake.
>
>I found that choosing CONFIG_BLK_DEV_RAM=m makes
>impossible to pass an initrd image since
>populate_rootfs() in init/initramfs.c omits
>code for checking whether the image is an initrd or not.

I believe it is (also?) due to /dev/ram0 not being available
where the initrd usually gets copied into.

initramfs continues to work, and that is what should I think
should be used for any new projects.

>But I didn't know CONFIG_BLK_DEV_RAM is tristate.
>So, I have to change to CONFIG_BLK_DEV_RAM=y when
>I want to pass an initrd image after "make allmodconfig".