files getting corrupted ?

[Josh Boyer]

On 11/21/05, alfred hitch <alfred.hitch at gmail.com> wrote:
> Hi,
>
> Need suggestions on a problem we are facing after a lot of usage and reboots.

NEEDINFO.  kernel version, MTD version, flash chip type, etc.

>
> ( Very basic questions )
>
> On the jffs2 (rw) partition, with MTD layer used to acceess it.
> We are observing executable file corruptions.
> If we jtag again, things are ok:
>  -> Meaning flash isn't corrupted (?)
>
>  -> It's an executable, so will adding sync anyways make a difference
> to reboot we have (not normal reboot command), but will it make any
> difference as it's to clear file i/o buffer s ?

Depends on the flash chip type.  Anything that uses the write buffer
will benefit from sync before reboot.  Even better, remount the fs as
read-only before reboot.

>
>  Read on an article on net that in basics of embedded design:
> ( http://www.linuxdevices.com/articles/AT2055943458.html )
>
>  -> Wear levelling should always been considered, wont MTD serve purpose here ?

No, MTD doesn't do wear leveling.  JFFS2 does.

>
>  -> What will be a good strategy for read / write of
> /var/log/messages, if writting in delayed / buffer forms isnt
> acceptable ?

One that writes as infrequently as possible to flash.

>
> -> jffs rw partition can affect due to frequent  write's
> executables(read only) in partition also
>  Executable in question happened to be sh(shell) !  a diff shows
> certain from middle of file were lost !

If you really want a section of flash to be read-only, partition it that way.

josh