Ubuntu 12.04 capricious behaviour and why only USB/CF loader

[softwarefailure]

I've just installed Ubuntu 12.04 from AmigaKit's Remix DVD and it doesn't always boot straight through, but quite often shows a kernel panic claiming

Unable to mount root fs on unknown-block(0,0)

I do have 2 GB RAM and the specified device name (/dev/sda4) is also correct. Whenever the error happens, the screen showing the two penguins stays there for a longer time and the Ubuntu boot screen doesn't show up at all. During a sane boot procedure the penguin screen is shown only for a fraction of a second before switching to the Ubuntu boot screen. If we're on the way to a kernel panic, however, the penguin screen is shown for about 30 seconds or so before the kernel panic appears.

I first thought it only happened when ethernet is plugged in but that's apparently not the case. However, unplugging the ethernet cable from the ethernet PCI card seems to improve the situation somewhat but that might also have been a coincidence. Does anyone else have these problems? It seems odd because I'm really using a stock X1000 with 2 GB RAM, 1 TB HD and a Radeon HD... nothing exotic really. Still Ubuntu 12.04 seems highly capricious to me... even the Live DVD doesn't always boot through but likes to fail with a

Unable to find a medium containing a live file system

error message

What's really annoying is that once it fails there is no way to reboot the machine so I have to power it off, wait 30 seconds, and power it on again. This can be really annoying if you have to try like 5 times just to get into Ubuntu and it's also not so healthy for the hardware. And it really does happen quite often.

=================================================

Another thing that is bothering me: Why does the kernel have to be on USB or CF? Why can't I just copy it to my Amiga partition and then do something like

Code: Select all

boot -elf -noints –fs=amigafs ide0.0:vmlinux3.10.15-ubuntu

The problem with using "usbdisk0:" is that it doesn't work from the CFE menu because the USB stick is not initialized yet at that time. So isn't it possible to fling the boot loader onto some HD drive? It doesn't seem to work with the Amiga partition but maybe it works with an extfs partition or something? Is that possible?

[Christopher Follett]

I've just installed Ubuntu 12.04 from AmigaKit's Remix DVD and it doesn't always boot straight through, but quite often shows a kernel panic claiming

Unable to mount root fs on unknown-block(0,0)

I do have 2 GB RAM and the specified device name (/dev/sda4) is also correct. Whenever the error happens, the screen showing the two penguins stays there for a longer time and the Ubuntu boot screen doesn't show up at all. During a sane boot procedure the penguin screen is shown only for a fraction of a second before switching to the Ubuntu boot screen. If we're on the way to a kernel panic, however, the penguin screen is shown for about 30 seconds or so before the kernel panic appears.

I first thought it only happened when ethernet is plugged in but that's apparently not the case. However, unplugging the ethernet cable from the ethernet PCI card seems to improve the situation somewhat but that might also have been a coincidence. Does anyone else have these problems? It seems odd because I'm really using a stock X1000 with 2 GB RAM, 1 TB HD and a Radeon HD... nothing exotic really. Still Ubuntu 12.04 seems highly capricious to me... even the Live DVD doesn't always boot through but likes to fail with a

Unable to find a medium containing a live file system

error message

What's really annoying is that once it fails there is no way to reboot the machine so I have to power it off, wait 30 seconds, and power it on again. This can be really annoying if you have to try like 5 times just to get into Ubuntu and it's also not so healthy for the hardware. And it really does happen quite often.

=================================================

Another thing that is bothering me: Why does the kernel have to be on USB or CF? Why can't I just copy it to my Amiga partition and then do something like

Code: Select all

boot -elf -noints –fs=amigafs ide0.0:vmlinux3.10.15-ubuntu

The problem with using "usbdisk0:" is that it doesn't work from the CFE menu because the USB stick is not initialized yet at that time. So isn't it possible to fling the boot loader onto some HD drive? It doesn't seem to work with the Amiga partition but maybe it works with an extfs partition or something? Is that possible?

Hi,

Could be you only have 2 GB RAM, it does state you need atleast 4GB.
I have tried many times booting from HDD, however the bootloader wont see the linux partition, but does see USB / CF.

[daz]

I've just installed Ubuntu 12.04 from AmigaKit's Remix DVD and it doesn't always boot straight through, but quite often shows a kernel panic claiming

Unable to mount root fs on unknown-block(0,0)

I do have 2 GB RAM and the specified device name (/dev/sda4) is also correct. Whenever the error happens, the screen showing the two penguins stays there for a longer time and the Ubuntu boot screen doesn't show up at all. During a sane boot procedure the penguin screen is shown only for a fraction of a second before switching to the Ubuntu boot screen. If we're on the way to a kernel panic, however, the penguin screen is shown for about 30 seconds or so before the kernel panic appears.

I first thought it only happened when ethernet is plugged in but that's apparently not the case. However, unplugging the ethernet cable from the ethernet PCI card seems to improve the situation somewhat but that might also have been a coincidence. Does anyone else have these problems? It seems odd because I'm really using a stock X1000 with 2 GB RAM, 1 TB HD and a Radeon HD... nothing exotic really. Still Ubuntu 12.04 seems highly capricious to me... even the Live DVD doesn't always boot through but likes to fail with a

Unable to find a medium containing a live file system

error message

What's really annoying is that once it fails there is no way to reboot the machine so I have to power it off, wait 30 seconds, and power it on again. This can be really annoying if you have to try like 5 times just to get into Ubuntu and it's also not so healthy for the hardware. And it really does happen quite often.

=================================================

Do you have a HD6870 graphics card by any chance? What you are describing is an obscure CFE bug that affects some systems with 2G ram, a Radeon card with a 256bit memory interface and an IOMMU enabled kernel.

For some reason, adding '-nousb' to the CFE bootargs seems to help.

so change your MENU_x_COMMAND end from:

; boot -elf -noints -fatfs cf0:vmlinux-3.10.15-ubuntu

; boot -elf -noints -nousb -fatfs cf0:vmlinux-3.10.15-ubuntu

and see if that helps.

Another thing that is bothering me: Why does the kernel have to be on USB or CF? Why can't I just copy it to my Amiga partition and then do something like

Code: Select all

boot -elf -noints –fs=amigafs ide0.0:vmlinux3.10.15-ubuntu

The problem with using "usbdisk0:" is that it doesn't work from the CFE menu because the USB stick is not initialized yet at that time. So isn't it possible to fling the boot loader onto some HD drive? It doesn't seem to work with the Amiga partition but maybe it works with an extfs partition or something? Is that possible?

There is a bug in CFE that means linux will only boot from an MBR partitioned disk. However this can be: a CF card, a USB disk, a SATA or IDE disk, and yes you could use a extfs2 partition if you wished. Most people use a CF card, and we recommend one as that is the best option.

Hope this helps
Regards
Darren

[softwarefailure]

Do you have a HD6870 graphics card by any chance? What you are describing is an obscure CFE bug that affects some systems with 2G ram, a Radeon card with a 256bit memory interface and an IOMMU enabled kernel.

No, I've a 5450.

For some reason, adding '-nousb' to the CFE bootargs seems to help.

I've tried -nousb and it seems to work a little better but once again, it could also be luck. Time will tell...

There is a bug in CFE that means linux will only boot from an MBR partitioned disk. However this can be: a CF card, a USB disk, a SATA or IDE disk, and yes you could use a extfs2 partition if you wished. Most people use a CF card, and we recommend one as that is the best option.

I've tried to use an extfs2 partition for it but it doesn't work. I've used GParted to create a 2 GB ext2 partition just for the bootloader. Trying to access this partitition from CFE, however, doesn't work. Here's what I get:

Code: Select all

CFE> dir -fs=ext2 ide0.6:
Could not init file system: File not found
*** command status = -18

CFE> boot -elf -noints -nousb -fs=ext2 ide0.6:vmlinux-3.10.15-ubuntu
Loader:elf Filesys:ext2 Dev:(null) File:ide0.6:vmlinux-3.10.15-ubuntu Options:(null)
Loading: Failed.
Could not load ide0.6:vmlinux-3.10.15-ubuntu: File not found
*** command status = -18

In GParted the partition appears as /dev/sda7 so I think "ide0.6" is the correct way to address it from CFE because partitions start at 0 here whereas /dev/sda starts at 1. Any idea why it doesn't work? One strange thing that I noticed: In GParted the partition is listed and formatted as "ext2" but once I mount it and select "Properties" it says "ext3/ext4" filesystem in Ubuntu... could this be the problem? Also, does the partition have to be bootable or require some other flags?

[mechanic]

Code: Select all

CFE> dir -fs=ext2 ide0.6:
Could not init file system: File not found
*** command status = -18

CFE> boot -elf -noints -nousb -fs=ext2 ide0.6:vmlinux-3.10.15-ubuntu
Loader:elf Filesys:ext2 Dev:(null) File:ide0.6:vmlinux-3.10.15-ubuntu Options:(null)
Loading: Failed.
Could not load ide0.6:vmlinux-3.10.15-ubuntu: File not found
*** command status = -18

The filesystem is probably allright, but it is on a RDB partition. You need a MBR partition.

[softwarefailure]

The filesystem is probably allright, but it is on a RDB partition. You need a MBR partition.

Is there a way to check if the HD uses RDB or MBR?

And if it's really RDB partitioned, is there a way to create an MBR as well? IIRC it is possible for RDB and MBR to co-exist somehow, isn't it?

[mechanic]

If it is formated for AmoigaOS it is RDB. That is to say, if you can add as many partitions as you want, or delete
partitions from the end it is RDB.

MBR can only have 4 true partitions, or 3 physical partitions and many logical partitions in the 4th physical
partition.

No, it is one or the other, RDB or MBR.

I have been running Linux since the early 90's . The best way to have two OS's on one computer is with 2 HDs.

[Christopher Follett]

Whats the bootargs in printenv?