Erreur Mount RootFS: VFS: Impossible d'ouvrir le périphérique racine "mtdblock4" ou le bloc inconnu (0,0)

Question

 
My MTD partition is: 
Creating 5 MTD partitions on "Physically mapped flash": 
0x00000000-0x00040000 : "UBoot" 
0x00040000-0x00060000 : "BDINFO" 
0x00060000-0x00100000 : "JFFS2" 
0x00100000-0x00380000 : "Kernel" 
0x00380000-0x00800000 : "Rootfs" 

Kernel command line is: 
Kernel command line: console=ttyS0,115200 mem=32M noinitrd root=/dev/mtdblock4 rw rootfstype=squashfs 

Now, error occurs when mount the root file system, kernel boot information as follows: 

## Checking Image at 81000000 ... 
    Image Name: Linux Kernel Image 
    Created:  2009-12-22 2:10:46 UTC 
    Image Type: MIPS Linux Kernel Image (gzip compressed) 
    Data Size: 874176 Bytes = 853.7 kB 
    Load Address: 80000000 
    Entry Point: 801fa000 
    Verifying Checksum ... OK 
RTL8389 # cp.b 0x80f60000 0xbd060000 401000 
Copy to Flash... done 
RTL8389 # ' 
RTL8389 # reset 

U-Boot 1.3.0 (Oct 2 2009 - 15:21:34) 

CPU: MIPS 4KEc 300 MHz, id: 0x90, rev: 0x6c 
Peripheral: 200 MHz 
DRAM: 32 MB 
Flash: 8 MB 
In: serial 
Out: serial 
Err: serial 
Chip configuration - $Revision: 5971 $ 
Switch Model: GS-2228 (Port Count: 28) 
Switch Chip: RTL8389M 
Net: rtl8389#0 
Press space to abort autoboot in 1 second 
## Booting image at bd100000 ... 
    Image Name: Linux Kernel Image 
    Created:  2009-12-22 2:10:46 UTC 
    Image Type: MIPS Linux Kernel Image (gzip compressed) 
    Data Size: 874176 Bytes = 853.7 kB 
    Load Address: 80000000 
    Entry Point: 801fa000 
    Verifying Checksum ... OK 
    Uncompressing Kernel Image ... OK 

Starting kernel ... 

Linux version 2.6.19 (root@localhost.localdomain) (gcc version 3.4.4 mipssde-6.03.00-20051020) #79 PREEMPT Mon Dec 21 21:10:37 EST 2009 
CPU revision is: 0001906c 
Determined physical RAM map: 
memory: 02000000 @ 00000000 (usable) 
User-defined physical RAM map: 
memory: 02000000 @ 00000000 (usable) 
Built 1 zonelists. Total pages: 8128 
Kernel command line: console=ttyS0,115200 mem=32M noinitrd root=/dev/mtdblock4 rw rootfstype=squashfs 
Primary instruction cache 16kB, physically tagged, 4-way, linesize 16 bytes. 
Primary data cache 16kB, 4-way, linesize 16 bytes. 
Synthesized TLB refill handler (20 instructions). 
Synthesized TLB load handler fastpath (32 instructions). 
Synthesized TLB store handler fastpath (32 instructions). 
Synthesized TLB modify handler fastpath (31 instructions). 
PID hash table entries: 128 (order: 7, 512 bytes) 
Dentry cache hash table entries: 4096 (order: 2, 16384 bytes) 
Inode-cache hash table entries: 2048 (order: 1, 8192 bytes) 
Memory: 30252k/32768k available (1668k kernel code, 2516k reserved, 351k data, 100k init, 0k highmem) 
Mount-cache hash table entries: 512 
Checking for 'wait' instruction... available. 
NET: Registered protocol family 16 
NET: Registered protocol family 2 
IP route cache hash table entries: 256 (order: -2, 1024 bytes) 
TCP established hash table entries: 1024 (order: 0, 4096 bytes) 
TCP bind hash table entries: 512 (order: -1, 2048 bytes) 
TCP: Hash tables configured (established 1024 bind 512) 
TCP reno registered 
JFFS2 version 2.2. (NAND) (C) 2001-2006 Red Hat, Inc. 
io scheduler noop registered 
io scheduler anticipatory registered 
io scheduler deadline registered 
io scheduler cfq registered (default) 
Serial: 8250/16550 driver $Revision: 1.90 $ 1 ports, IRQ sharing disabled 
serial8250: ttyS0 at MMIO 0x0 (irq = 31) is a 16550A 
flash device: 2000000 at bd000000 
Physically mapped flash: Found 1 x16 devices at 0x0 in 16-bit bank 
Amd/Fujitsu Extended Query Table at 0x0040 
number of CFI chips: 1 
cfi_cmdset_0002: Disabling erase-suspend-program due to code brokenness. 
Creating 5 MTD partitions on "Physically mapped flash": 
0x00000000-0x00040000 : "UBoot" 
0x00040000-0x00060000 : "BDINFO" 
0x00060000-0x00100000 : "JFFS2" 
0x00100000-0x00380000 : "Kernel" 
0x00380000-0x00800000 : "Rootfs" 
TCP cubic registered 
NET: Registered protocol family 1 
NET: Registered protocol family 17 
VFS: Cannot open root device "mtdblock4" or unknown-block(0,0) 
Please append a correct "root=" boot option 
Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0) 

Quelle est la cause?

Answer 1

Ce problème a été résolu.
la résolution est ouvrir l'élément de configuration CONFIG_SYSFS.