Booting from /dev/mtdblock/0

Booting from /dev/mtdblock/0

[Murtada Shah]

Hi,

I'm trying to boot from /dev/mtdblock/0 (root=/dev/mtdblock/0 in cmdline 
options)

When I boot from nfs, I can mount /dev/mtdblock/0 no problem from 
command line & unmount etc.

But if I pass it as the root= option, while booting it gets stuck.

With mtd debug level to 3 I see that it tries mtdblock_open twice... 
which it shouldnt..

"mtdblock_open
ok
mtdblock_open
mtdblock_release"

Then it hangs here for a long time.
What could be the cause?

Murtada

Re: Booting from /dev/mtdblock/0

[John Weston]

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G'day,

Have not got to the bottom of this yet, but having the same problem. We had
a development board which worked fine using kernel version 2.4.3 but since
updating to 2.4.18 we are now seeing the same problem.

Does anyone know of any required patches for this?

Thanks

John Weston



Mutada Shah wrote:

> Hi,
>
> I'm trying to boot from /dev/mtdblock/0 (root=/dev/mtdblock/0 in cmdline
> options)
>
> When I boot from nfs, I can mount /dev/mtdblock/0 no problem from
> command line & unmount etc.
>
> But if I pass it as the root= option, while booting it gets stuck.
>
> With mtd debug level to 3 I see that it tries mtdblock_open twice...
> which it shouldnt..
>
> "mtdblock_open
> ok
> mtdblock_open
> mtdblock_release"
>
> Then it hangs here for a long time.
> What could be the cause?
>
> Murtada
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/

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Re: Booting from /dev/mtdblock/0

[John Weston]

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Hi again,

Pardon my last message. Having looked up the mail archive found the solution
there. Seems to be a problem calling the invalidate_device function call in
the mtdblock.c code.

Seems like I had better look harder next time.

Thanks anyway.

John Weston


John Weston wrote:

> G'day,
>
> Have not got to the bottom of this yet, but having the same problem. We had
> a development board which worked fine using kernel version 2.4.3 but since
> updating to 2.4.18 we are now seeing the same problem.
>
> Does anyone know of any required patches for this?
>
> Thanks
>
> John Weston
>
> Mutada Shah wrote:
>
> > Hi,
> >
> > I'm trying to boot from /dev/mtdblock/0 (root=/dev/mtdblock/0 in cmdline
> > options)
> >
> > When I boot from nfs, I can mount /dev/mtdblock/0 no problem from
> > command line & unmount etc.
> >
> > But if I pass it as the root= option, while booting it gets stuck.
> >
> > With mtd debug level to 3 I see that it tries mtdblock_open twice...
> > which it shouldnt..
> >
> > "mtdblock_open
> > ok
> > mtdblock_open
> > mtdblock_release"
> >
> > Then it hangs here for a long time.
> > What could be the cause?
> >
> > Murtada
> >
> > ______________________________________________________
> > Linux MTD discussion mailing list
> > http://lists.infradead.org/mailman/listinfo/linux-mtd/

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Re: Booting from /dev/mtdblock/0

[Jim Thompson]

Its a one-line fix.

    static release_t mtdblock_release(struct inode *inode, struct file *file)
    {
	    int dev;
	    struct mtdblk_dev *mtdblk;
	    DEBUG(MTD_DEBUG_LEVEL1, "mtdblock_release\n", inode);

	    if (inode == NULL)
		    release_return(-ENODEV);

    #if 0
	    invalidate_device(inode->i_rdev, 1);
    #endif



John Weston writes:
> G'day,
> 
> Have not got to the bottom of this yet, but having the same problem. We had
> a development board which worked fine using kernel version 2.4.3 but since
> updating to 2.4.18 we are now seeing the same problem.
> 
> Does anyone know of any required patches for this?
> 
> Thanks
> 
> John Weston
> 
> 
> 
> Mutada Shah wrote:
> 
> > Hi,
> >
> > I'm trying to boot from /dev/mtdblock/0 (root=/dev/mtdblock/0 in cmdline
> > options)
> >
> > When I boot from nfs, I can mount /dev/mtdblock/0 no problem from
> > command line & unmount etc.
> >
> > But if I pass it as the root= option, while booting it gets stuck.
> >
> > With mtd debug level to 3 I see that it tries mtdblock_open twice...
> > which it shouldnt..
> >
> > "mtdblock_open
> > ok
> > mtdblock_open
> > mtdblock_release"
> >
> > Then it hangs here for a long time.
> > What could be the cause?
> >
> > Murtada
> >
> > ______________________________________________________
> > Linux MTD discussion mailing list
> > http://lists.infradead.org/mailman/listinfo/linux-mtd/

-- 
"Life begins when you can spend your spare time programming
instead of watching television."  -- Cal Keegan