Find the answer to your Linux question:
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 14
Hello! I am trying to boot my freshly compiled linux kernel (2.6.35.5) but it boots to a certain point and then gives a kernel panic. It says that it cannot ...
Enjoy an ad free experience by logging in. Not a member yet? Register.
  1. #1
    Just Joined!
    Join Date
    Sep 2010
    Posts
    7

    Exclamation Kernel booting problem


    Hello!

    I am trying to boot my freshly compiled linux kernel (2.6.35.5) but it boots to a certain point and then gives a kernel panic. It says that it cannot mount the VFS so I passed on a root=/dev/sdb1 parameter to the kernel (grub) but then it says to me that /dev/sdb1 is not a valid mount point? I am trying to boot it of my bootable usb stick with grub.
    The kernel is compiled without initial ramdisk support. I also tried some other arguments like : root=/media/cdrom (when booting from a grub bootable cd) but this also gives the same error. However this time the kernels says that I should try passing a root parameter for the cd drive? possible arguments are : 0xb00 sr : sr0
    But passing these also does not work.

    Can someone please help me on how to boot the kernel from a usb stick?
    I tried the bzImage for booting and the vmlinuz one but both act the same.

    Thank you for reading

  2. #2
    Linux Engineer Segfault's Avatar
    Join Date
    Jun 2008
    Location
    Acadiana
    Posts
    877
    I've never played with bootable USB sticks myself, but common sense tells us following:
    There is a PC with this stick plugged in, it has all kind of devices, including unknown number of hard drives.
    USB stick is accessed thru SCSI layer, thus it is given node name sd as is given to hard drives.
    Obviously, when you plug it into a box which has one drive it will be sdb, this is not going to be the case if the PC has two or more drives.
    Thus, your best bet is to access it by UUID.

  3. #3
    Just Joined!
    Join Date
    Sep 2010
    Posts
    7
    Hello,

    Thank you for your fast reply I tried to root with the UUID, However this resulted in the same error. Is there any possible way to pass on a root fs with usb booting or cd booting?

    Can someone please point me into the right direction?

    Thank you for reading

  4. #4
    Linux Guru coopstah13's Avatar
    Join Date
    Nov 2007
    Location
    NH, USA
    Posts
    3,149
    if you aren't using initrd, then you need to make sure that the drivers required to see/mount the filesystem on the USB drive are compiled into the kernel

  5. #5
    Just Joined!
    Join Date
    Sep 2010
    Posts
    7
    Well I am creating a initrd now to not to grow the kernel to much in size hehe.

    Thanks for your help!

    EDIT:
    I still cannot seem to get it to work :/ (using virtualbox this time with an iso image)
    this is the output:

    Code:
    RAMDISK: cramfs filesystem found at block 0
    RAMDISK: image too big! (76889Kib/65536Kib)
    VFS: Cannot open root device "/initrd" or unknown block(0,0)
    Please append a correct "root=" boot option; here are the available partitions:
    0b00        1048575  sr0 driver: sr
    0800          249856 sda driver: sd
    Kernal panic - not syncing: VFS: unable to mount root fs on unknown block(0,0)
    as root="" I tried: cdrom , cd-rom , /dev/sdb1, 0b00, 0b800 ,
    And it still gives the same output error :/
    Does someone know how I can fix this?
    Last edited by zyvo; 09-25-2010 at 05:48 PM.

  6. #6
    Linux Engineer Segfault's Avatar
    Join Date
    Jun 2008
    Location
    Acadiana
    Posts
    877
    unknown block(0,0)
    This error implies your kernel is unable to access the drive. In your case, it means you have not enabled required USB and SCSI options.

  7. #7
    Just Joined!
    Join Date
    Sep 2010
    Posts
    7
    Ahh how dumb of me.. I thought that I compiled these drivers into the kernel but I accidently compiled them as modules hehe my mistake. Recompiling the kernel now and willpost if it worked or not

    [EDIT]
    I recompiled my kernel and I built in the scsi and usb drivers and it still give me the same error. I recompiled even with all the usb / scsi drivers and even made a new initrd but no working result :/
    Last edited by zyvo; 09-26-2010 at 09:04 AM.

  8. #8
    Linux Engineer Segfault's Avatar
    Join Date
    Jun 2008
    Location
    Acadiana
    Posts
    877
    unknown block(0,0)
    Is this the same error or are the numbers different now?

  9. #9
    Just Joined!
    Join Date
    Sep 2010
    Posts
    7
    Yep its the same :/

    Code:
     VFS: cannot open root device = "/initrd" or unknown-block(0,0)
    I also tried : /dev/sdb1 , sr, sd, sr0, cd-rom , cdrom , /media/cdrom
    Quite strange

    My environment is (not that it helps I dont know :/)
    -ubuntu 10.04 latest stable gcc, g++

  10. #10
    Linux Engineer Segfault's Avatar
    Join Date
    Jun 2008
    Location
    Acadiana
    Posts
    877
    What's the kernel command line in your bootloader?

Page 1 of 2 1 2 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •