[Qemu-ppc] VFS: Cannot open root device "hda" or unknown-block(2, 0)

[Elvis Dowson]

Hi,

      I managed to get the qemu-system-ppc emulator to boot with the xilinx xps_ethlite MAC. 

I'm just stuck with the kernel not being able to find the rootfs. I have specified -hda as follows, in my qemu-run.sh script:

MACH="-M virtex-ml507"

QEMU=/project/qemu/ppc-softmmu/qemu-system-ppc

KERNEL="-kernel uImage"

ROOTFS="-hda core-image-minimal-virtex5.ext3"

$QEMU $MACH $BOOTROM $NIC0 $KERNEL $ROOTFS -m 256 -append "root=/dev/hda rw console=ttyS0 console=ttyS0 mem=256M" -nographic $*

This is the output of the kernel boot process for the Xilinx ML507 machine is shown below, it gets stuck with the message VFS: Cannot open root device "hda" or unknown-block(2,0) :

address@hidden:/project/qemu-system-ppc-virtex5-ml507-yocto$ ./qemu-run.shUsing Xilinx Virtex440 machine description

Linux version 3.0.0-14.1-build3 (address@hidden) (gcc version 4.7.1 20120421 (prerelease) (GCC) ) #1 PREEMPT Thu Jun 7 23:29:16 CEST 2012

Zone PFN ranges:

  DMA      0x00000000 -> 0x00010000

  Normal   empty

Movable zone start PFN for each node

early_node_map[1] active PFN ranges

    0: 0x00000000 -> 0x00010000

MMU: Allocated 1088 bytes of context maps for 255 contexts

Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 65024

Kernel command line: root=/dev/hda rw console=ttyS0 mem=256M

PID hash table entries: 1024 (order: 0, 4096 bytes)

Dentry cache hash table entries: 32768 (order: 5, 131072 bytes)

Inode-cache hash table entries: 16384 (order: 4, 65536 bytes)

Memory: 254540k/262144k available (3940k kernel code, 7604k reserved, 132k data, 1139k bss, 168k init)

Kernel virtual memory layout:

  * 0xfffdf000..0xfffff000  : fixmap

  * 0xfde00000..0xfe000000  : consistent mem

  * 0xfde00000..0xfde00000  : early ioremap

  * 0xd1000000..0xfde00000  : vmalloc & ioremap

Preemptible hierarchical RCU implementation.

NR_IRQS:512 nr_irqs:512 16

clocksource: timebase mult[a00000] shift[22] registered

Console: colour dummy device 80x25

pid_max: default: 32768 minimum: 301

Mount-cache hash table entries: 512

devtmpfs: initialized

NET: Registered protocol family 16

PCI: Probing PCI hardware

bio: create slab <bio-0> at 0

XGpio: /address@hidden/address@hidden: registered

XGpio: /address@hidden/address@hidden: registered

XGpio: /address@hidden/address@hidden: registered

XGpio: /address@hidden/address@hidden: registered

vgaarb: loaded

Switching to clocksource timebase

NET: Registered protocol family 2

IP route cache hash table entries: 2048 (order: 1, 8192 bytes)

TCP established hash table entries: 8192 (order: 4, 65536 bytes)

TCP bind hash table entries: 8192 (order: 3, 32768 bytes)

TCP: Hash tables configured (established 8192 bind 8192)

TCP reno registered

UDP hash table entries: 256 (order: 0, 4096 bytes)

UDP-Lite hash table entries: 256 (order: 0, 4096 bytes)

NET: Registered protocol family 1

RPC: Registered named UNIX socket transport module.

RPC: Registered udp transport module.

RPC: Registered tcp transport module.

RPC: Registered tcp NFSv4.1 backchannel transport module.

ROMFS MTD (C) 2007 Red Hat, Inc.

JFS: nTxBlock = 1996, nTxLock = 15972

msgmni has been set to 499

Block layer SCSI generic (bsg) driver version 0.4 loaded (major 254)

io scheduler noop registered

io scheduler deadline registered

io scheduler cfq registered (default)

Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled

83e00000.serial: ttyS0 at MMIO 0x83e01003 (irq = 20) is a 16550

console [ttyS0] enabled

brd: module loaded

loop: module loaded

xsysace 83600000.sysace: xsysace: error initializing device at 0x83600000

xsysace 83600000.sysace: could not initialize device, err=-12

xsysace: probe of 83600000.sysace failed with error -12

Xilinx SystemACE device driver, major=254

pflash_write: Unimplemented flash cmd sequence (offset 00000000, wcycle 0x0 cmd 0x0 value 0xf0f0)

of-flash fc000000.flash: do_map_probe() failed

xilinx_emaclite 81000000.ethernet: Device Tree Probing

xilinx_emaclite 81000000.ethernet: error registering MDIO bus

xilinx_emaclite 81000000.ethernet: MAC address is now 00:0a:35:22:b2:00

xilinx_emaclite 81000000.ethernet: Xilinx EmacLite at 0x81000000 mapped to 0xD11C0000, irq=17

mousedev: PS/2 mouse device common for all mice

TCP cubic registered

NET: Registered protocol family 17

Root-NFS: no NFS server address

VFS: Unable to mount root fs via NFS, trying floppy.

VFS: Cannot open root device "hda" or unknown-block(2,0)

Please append a correct "root=" boot option; here are the available partitions:

Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(2,0)

Call Trace:

[cf82dec0] [c0006790] show_stack+0x48/0x150 (unreliable)

[cf82df00] [c0304b1c] panic+0xac/0x1c4

[cf82df50] [c03afbb4] mount_block_root+0x190/0x23c

[cf82dfa0] [c03afe64] mount_root+0xcc/0xe0

[cf82dfc0] [c03b0014] prepare_namespace+0x19c/0x1e4

[cf82dfd0] [c03af85c] kernel_init+0x10c/0x110

[cf82dff0] [c000b79c] kernel_thread+0x4c/0x68

Rebooting in 180 seconds..

What could be causing this? An incorrect defconfig? 

Elvis DOwson