Charles Manning <manningc2@actrix.gen.nz> writes:

> On Monday 09 August 2010 19:31:10 Henrik Grindal Bakken wrote:
>
>> I'm bringing this up again.
>>
>> I'm using yaffs (2) on a NAND flash, and on the yaffs fs, I have
>> among other files some file system images (ext2), which are
>> loopback-mounted.  If I touch a file on the loopback-mounted image,
>> sync, then poweroff, the file is lost when the box comes up again.
>>
>> I notice that yaffs_sync_fs is no longer a nop, but it apparently
>> doesn't quite do what I need it to.
>>
>> Does anyone have any idea how one could go about attacking this
>> problem?
>
> Hello Hendrik
>
> Have you tried enabling tracing to see what is happening?
>
> #echo +os >/proc/yaffs
>
> I wonder if perhaps the file system syncing order does something like this:
>
> # sync:
> 	sync yaffs yaffs is now sync'ed
> 	sync ext2 yaffs is now dirty again
>
> What happens if you sync twice?
>
> # sync; sleep 2; sync
>
> -- Charles

Hi Charles, and thanks for a quick reply.

Here's a paste of dmesg following these commands:
$ echo "+os" > /proc/yaffs
$ touch /config/3
$ sync
<a few seconds of waiting>
$ sync
<poweroff>

   http://fpaste.org/uumk/

When it comes back up, the file does not exist.  I also tried sync;
sleep 4; sync, with the same result.


-- 
Henrik Grindal Bakken <hgb@ifi.uio.no>
PGP ID: 8D436E52
Fingerprint: 131D 9590 F0CF 47EF 7963  02AF 9236 D25A 8D43 6E52