Re: UBIFS mount failure upon power off

[Mark <xiaoming1981.zhang@gmail.com>]

On 04/22/2012 09:15 PM, Artem Bityutskiy wrote:
> Hi,
>
> On Wed, 2012-04-11 at 20:17 +0800, Mark wrote:
>>  brcmnand_read_page: 3: brcmnand_posted_read_cache failed at
>>  offset=3c81c00, ret=-77
>>  UBI error: ubi_io_read: error -77 while reading 126976 bytes from PEB
>>  21:4096, read 2048 bytes
>>  UBIFS error (pid 484): ubifs_start_scan: cannot read 126976 bytes from
>>  LEB 18:0, error -5
>>  mount: mounting ubi13_0 on /usr/local/appdata failed: Input/output
>>  error
>>
> Please fix your NAND driver and why it returns strange error code
> -EBADFD (-77). Uncorrectable ECC errors should be reported as -EBADMSG
> instead. Bit-flips as -EUCLEAN.
>

Thank you very much, I still have some questions:

1. I'm using mips platform so I think "-77" is "-EBADMSG":
       ./arch/mips/include/asm/errno.h:51:#define      EBADMSG 
77      /* Not a data message */

2. I found these comments in ubi_io_read():
	        /* 
 

                  * The driver should never return -EBADMSG if it failed 
to read 

                  * all the requested data. But some buggy drivers might 
do 

                  * this, so we change it to -EIO. 
 

                  */

    but seems my nand driver do_read_ops() function returns immediately
    on an ecc error. Why the driver must continue reading the left data?

3. I fixed this problem, in most situations the ubifs can recover 
successfully,
    but I still get this error (though difficult to reproduce):

        UBI error: ubi_io_read: error -77 while reading 126976 bytes 
from PEB 2:4096, read 126976 bytes
        UBIFS error (pid 481): insert_node: duplicate sqnum in replay
        mount: mounting ubi13_0 on /usr/local/hmt/appdata failed: 
Invalid argument

    What could be the reason?

4. The problem mentioned in #2 and #3 never happens with yaffs2.

Thank you very much.

-- 
Have fun,
Mark Zhang