# VFS: Cannot open root device Mushkin MKNSSDCL SSD [solved]

## oneself

Hi,

I have a working configuration using genkernel on my Thinkpad X200s.  All the hardware works.  I'm currently trying to get a leaner kernel working using "make localmodconfig".  The first problem I am encountering is that my SSD is not working with the new kernel.

I am using a Mushkin SSD:

```
# lshw -class disk -class storage

  *-storage               

       description: SATA controller

       product: 82801IBM/IEM (ICH9M/ICH9M-E) 4 port SATA Controller [AHCI mode]

       vendor: Intel Corporation

       physical id: 1f.2

       bus info: pci@0000:00:1f.2

       logical name: scsi0

       version: 03

       width: 32 bits

       clock: 66MHz

       capabilities: storage msi pm ahci_1.0 bus_master cap_list emulated

       configuration: driver=ahci latency=0

       resources: irq:44 ioport:1c48(size=8) ioport:183c(size=4) ioport:1c40(size=8) ioport:1838(size=4) ioport:1c20(size=32) memory:f2826000-f28267ff

     *-disk

          description: ATA Disk

          product: Mushkin MKNSSDCL

          physical id: 0.0.0

          bus info: scsi@0:0.0.0

          logical name: /dev/sda

          version: 343A

          serial: MKN11100000012948

          size: 223GiB (240GB)

          capabilities: partitioned partitioned:dos

          configuration: ansiversion=5 signature=02990dd9

```

When I boot up I get the following:

```
VFS: Cannot open root device "sda2" or unknown-block(0,0)
```

I'm fairly certain that my kernel is misconfigured in some way, but I'm not sure what I need to add to make this HD work.

Thank you

----------

## NeddySeagoon

oneself,

Start with one of the seed kernels from kernel-seeds.org. Pappy has a sticky support thread in Unsupported Software.

make localmodconfig makes a fully modular kernel, which means you will need an initrd to load the kernel modues you need for booting.

You can avoid an initrd while you learn about the kernel.

The key line in your post is 

```
       description: SATA controller 

       product: 82801IBM/IEM (ICH9M/ICH9M-E) 4 port SATA Controller [AHCI mode]
```

This tells that you need SCSI Disk support built into your kernel, and the AHCI SATA driver.

In addition your will need the driver for your root filesystem configured as <*>.  We don't know what this is.

Your unknown-block(0,0) error gives the kernel major,minor numbers of the device the kernel is trying to access.  (0,0) does not exist. It means the kernel cannot talk to you hard drive at all.

The numbers here are key to the diagnoses of further errors.

----------

## oneself

Thank you,

Setting the following options in my .config file from "m" to "y" solved the problem:

```
CONFIG_SATA_AHCI=y

CONFIG_SATA_AHCI_PLATFORM=y

CONFIG_SATA_ACARD_AHCI=y

```

----------

