# ahci driver not

## cgmoller

Hello

I recently swapped out one motherboard and CPU for another.  To do so I backed up rootfs, booted off a live CD repartitioned the drive (rootfs is ext4 and boot is ext2) and restored the system and then rebuilt the kernel.  The motherboard is set to AHCI mode and the controller driver is built into the kernel.

```
(CHROOT) livecd linux # lspci -vs 00:11

00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD/ATI] SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] (rev 40) (prog-if 01 [AHCI 1.0])

        Subsystem: Micro-Star International Co., Ltd. [MSI] SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode]

...

        Kernel driver in use: ahci
```

```
(CHROOT) livecd linux # grep -i ahci .config

CONFIG_SATA_AHCI=y

CONFIG_SATA_AHCI_PLATFORM=y

# CONFIG_SATA_ACARD_AHCI is not set
```

This all worked nicely and was back in business (successful reboot followed by other system updates) but suddenly I am getting a kernel panic:

not syncing: VFS: unable to mount root fs on unknown-block(0,0)

I have rebuilt this drive a couple of times since and tried UEFI - all to no avail.  I suspect that the drive is just failing ... annoyingly gracefully.

If it worked once before, should I just replace the drive?

----------

## Logicien

Hello,

have-you adapt well your Linux kernel configuration to the new motherboard, the Cpu and boot mode (Bios, Uefi)? What type of partitions table do you sue for each (Dos/Mbr, Gpt)? Recompile the kernel with the new material is one thing. All the rest stay compile with the previous material.

For example, your processor type may be different now than before. If set, the Gcc -march -mcpu and -mtune parameters may have to be change in /etc/portage/make.conf. Recompile all packages with emerge --emptytree may make a difference.

In a case like this I try to use several Linux distributions (on live) to see if things work in a way. If not I start to think that Linux do not support the material and/or the material is buggy.

If the problem persist reinstall Gentoo from scratch would be my last try.

----------

## cgmoller

Logicien

To answer your questions, I use mbr, though I briefly experimented with GPT.  I had also updated the processor architecture in make.conf.

I will try your suggestions when I get a chance.  Probably over the weekend.  

Thank you.

----------

## Roman_Gruber

 *Quote:*   

> not syncing: VFS: unable to mount root fs on unknown-block(0,0) 

 

Just impllies that your knerel is unable to find your root.

Means

No build in (Y not module) support for your disc controller in the kernel. No file system support in your kernel.

Please boot up a liveced, check out lspci -kk, write down the kernel modules in use, and build them in your kernel.

you may try genkernel and see if it works out of the box.

VEry often the kernel options needed are well hidden in STAGING / EXPERIMENTAL branch of the kernel.

----------

