[elbe-users] Problem with ubifs

[Manuel Traut]

On Mon, Feb 26, 2018 at 07:49:13PM +0100, Ralf Schlatterbeck wrote:
> I have a project where I create an UBIFS.
> This used to run on Debian oldstable (jessie) with elbe-testing and
> generated an image for oldstable.
> I'm now trying to port this to debian stable using elbe (without
> -testing). I'm getting a corrupt ubifs which gets me a kernel panic.
> (kernel messages below)
> 
> Trying to unpack that image with the python project ubi-reader
> https://github.com/jrspruitt/ubi_reader
> I'm getting "UBIFS Fatal: Super block error: Wrong node type."
> which leads me to believe the resulting ubi image is really corrupt.
> 
> The image got larger with debian stable, can it be that I'm silently
> creating an image that is too big to fit into the ubi data structures
> without an error message?
> The resulting image (uncompressed nand.img, elbe builds nand.img.gz) is
> now 35.9 MB while the old images (debian oldstable) were around 27.3 MB
> 
> In the elbe log.txt I have:
> running cmd +mkfs.ubifs -r /var/cache/elbe/c90792e3-2d82-4753-8e56-1ae61da056d2/filesystems/0 -o /var/cache/elbe/c90792e3-2d82-4753-8e56-1ae61da056d2/rootfs.ubifs -m 2048 -e 126976 -c 256 -x lzo+
> ------------------------------------------------------------------------------
> Error: max_leb_cnt too low (272 needed)
> ------------------------------------------------------------------------------
> 
> Command failed with errorcode 255
> 
> Looks like my number of logical erase blocks is too low for the
> generated image of around 35M.
> 
> If this is critical (and the reason for the failure): Shouldn't Elbe raise an
> error here instead of silently creating a corrupt image?

elbe just uses the output of the mtd-utils. If they produce an output you don't
expect i think it's more a mtd-utils issue than a elbe issue.

However we could check the return value of mkfs.ubifs, ubinize etc. and log
some 'critical' error as soon as we have this feature:

https://github.com/Linutronix/elbe/issues/146

> Elbe xml part of the ubi image:
> 
>     <images>
>       <mtd>
>         <name>nand.img</name>
>         <nr>0</nr>
>         <size>61184kB</size>
>         <ubivg>
>           <label>nand</label>
>           <miniosize>2048</miniosize>
>           <maxlogicaleraseblockcount>256</maxlogicaleraseblockcount>
>           <logicaleraseblocksize>126976</logicaleraseblocksize>
>           <physicaleraseblocksize>128KiB</physicaleraseblocksize>
>           <ubi>
>             <type>dynamic</type>
>             <label>rootfs</label>
>             <id>0</id>
>             <size>40MiB</size>
>           </ubi>
>         </ubivg>
>       </mtd>
>     </images>
> 
> Kernel messages when booting:
> ubi0: attaching mtd3
> ubi0: scanning is finished
> ubi0: attached mtd3 (name "rootfs1", size 59 MiB)
> ubi0: PEB size: 131072 bytes (128 KiB), LEB size: 126976 bytes
> ubi0: min./max. I/O unit sizes: 2048/2048, sub-page size 2048
> ubi0: VID header offset: 2048 (aligned 2048), data offset: 4096
> ubi0: good PEBs: 478, bad PEBs: 0, corrupted PEBs: 0
> ubi0: user volume: 1, internal volumes: 1, max. volumes count: 128
> ubi0: max/mean erase counter: 1/0, WL threshold: 4096, image sequence number: 1672873418
> ubi0: available PEBs: 123, total reserved PEBs: 355, PEBs reserved for bad PEB handling: 20
> ubi0: background thread "ubi_bgt0d" started, PID 742
> stmp3xxx-rtc 80056000.rtc: setting system clock to 1970-01-01 00:20:53 UTC (1253)
> uart-pl011 80074000.serial: no DMA platform data
> List of all partitions:
> 0100           16384 ram0 
>  (driver?)
> 0101           16384 ram1 
>  (driver?)
> 0102           16384 ram2 
>  (driver?)
> 0103           16384 ram3 
>  (driver?)
> 1f00            1024 mtdblock0 
>  (driver?)
> 1f01             384 mtdblock1 
>  (driver?)
> 1f02            6144 mtdblock2 
>  (driver?)
> 1f03           61184 mtdblock3 
>  (driver?)
> 1f04           61184 mtdblock4 
>  (driver?)
> 1f05             512 mtdblock5 
>  (driver?)
> 1f06             512 mtdblock6 
>  (driver?)
> 1f07            4096 mtdblock7 
>  (driver?)
> No filesystem could mount root, tried: 
>  ubifs
> 
> Kernel panic - not syncing: VFS: Unable to mount root fs on unknown-block(0,0)
> CPU: 0 PID: 1 Comm: swapper Not tainted 4.14.21-karo+ #1
> Hardware name: Freescale MXS (Device Tree)
> ...
> 
> Ralf
> -- 
> Dr. Ralf Schlatterbeck                  Tel:   +43/2243/26465-16
> Open Source Consulting                  www:   http://www.runtux.com
> Reichergasse 131, A-3411 Weidling       email: office at runtux.com
> 
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