Re: [Qemu-discuss] Kernel panic when booting from SCSI disk

[Mike Lovell]

On 07/30/2012 12:12 AM, Thomas Oberhammer wrote:
> I tried different things, but the situation is unchanged.
>
> Conversion of the disks:
> ------------------------
>
> I started with the vmdk files that were contained in the ova.
> I was not able to boot them, neither with if=ide, nor with if=scsi.
> (The error message was: no bootable devices found)
>
> After that, I converted the disks:
> vmware-vdiskmanager -r disk1.vmdk -t 0 disk1_t0.vmdk
>
> Now, qemu found a bootable device, but the error was the same as 
> described in the original post.
>
> The next step was to convert the disk to qcow2 format:
> qemu-img convert disk1_t0.vmdk -O qcow2 disk1.qcow2
>
> But also after this, the situation was still the same.
>
>
> Boot loader parameters:
> -----------------------
>
> The current boot loader parameters are:
>
> root (hd0,1)
> kernel /vmlinuz root=LABEL=ROOT1
> initrd /initrd.img
>
>
> I tried root=/dev/... with sda, sda1, sda5, hda, hda1, hda5, disk0p5
> in combination with if=ide and if=scsi
>
> The only combination that did not create a kernel panic was
> if=ide and root=/dev/hda5
>
>
> I also enabled the debugging option, giving a little more insights 
> what actually caused the kernel panic:
> (as you said, it cannot find the root file system)
>
> Setting up fail make_request
> Freeing unused kernel memory: 200k freed
> Mounted /proc filesystem
> Mounting sysfs
> Creating /dev
> Starting udev
> Waiting for root device
> Waiting for ROOT filesystem to become available [ROOT1]
> Waiting for ROOT filesystem to become available [ROOT1]
> [...]
> ERROR: Unable to find root device ROOT1
> Creating root device
> Mounting root filesystem
> mount: Mounting /dev/root on /sysroot failed: No such file or directory
> mount: Mounting /dev on /sysroot/dev failed: No such file or directory
> mount: Mounting /proc on /sysroot/proc failed: No such file or directory
> mount: Mounting /dev/root on /sysroot failed: Invalid argument
> Switching to new root
> switch_root: bad newroot /sysroot
> Kernel panic - not syncing: Attempted to kill init!
>
>
> I wonder what the right path would be to access a disk that is 
> attached via
> -drive file=diskname,if=scsi

sorry for the delay in a response. the email got lost in the inbox.

if you use 'if=scsi' on the command line, the disk should show up to the 
guest as /dev/sd*. if the system is still throwing a kernel panic during 
boot it is possible that the guest doesn't have drivers for the proper 
scsi controller. i don't remember what scsi controller vmware emulates 
but i just checked on qemu and the scsi controller it emulates is a 
LSI/Symbios 53c895a. it looks like the linux 3.2 kernel driver is 
sym53c8xx. i don't know what distribution you're using or if the 2.6.9 
kernel compiles this by default. checking to make sure the guest can see 
this kind of controller would be the next place that i would look.

mike