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Date: Wed, 30 May 2001 17:41:21 -0700
From: Jun Sun <jsun@mvista.com>
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To: Ian Thompson <iant@palmchip.com>
CC: linux-mips@oss.sgi.com
Subject: Re: ramdisk funkiness
References: <3B157A53.5728029@palmchip.com>
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Ian Thompson wrote:
> 
> Hi,
> 
> I'm porting the 2.4 kernel to a custom board, and I'm running into some
> trouble while trying to mount the root filesystem.  There is no media
> (hard drives, cdrom drives, etc) attached to the system, but of course
> the kernel needs a root filesystem to boot.  So, I'm trying to create an
> empty ramdisk and have the kernel mount that as the root fs.  The kernel
> installs the ramdisk driver fine, but when it tries to open the ramdisk,
> I get this error message:
> 
> RAMDISK driver initialized: 16 RAM disks of 128K size 1024 blocksize
> VFS: Cannot open root device "ram0" or 01:00
> Please append a correct "root=" boot option
> Kernel panic: VFS: Unable to mount root fs on 01:00
>

You don't need to supply "root=/dev/ram0" argument as long as you give the
configure in the following option:

 Initial RAM disk (initrd) support (CONFIG_BLK_DEV_INITRD)

Jun