seeking help on JFFS2

[Junping Zhang]

I specified CONFIG_MTD_CFI_INTELEXT only. Here is that section in .config
-----------------------------------------------------------
# CONFIG_MTD_CFI is not set
CONFIG_MTD_JEDECPROBE=y
CONFIG_MTD_GEN_PROBE=y
CONFIG_MTD_CFI_ADV_OPTIONS=y
CONFIG_MTD_CFI_NOSWAP=y
# CONFIG_MTD_CFI_BE_BYTE_SWAP is not set
# CONFIG_MTD_CFI_LE_BYTE_SWAP is not set
CONFIG_MTD_CFI_GEOMETRY=y
# CONFIG_MTD_CFI_B1 is not set
# CONFIG_MTD_CFI_B2 is not set
CONFIG_MTD_CFI_B4=y
# CONFIG_MTD_CFI_B8 is not set
# CONFIG_MTD_CFI_I1 is not set
# CONFIG_MTD_CFI_I2 is not set
CONFIG_MTD_CFI_I4=y
# CONFIG_MTD_CFI_I8 is not set
CONFIG_MTD_CFI_INTELEXT=y
# CONFIG_MTD_CFI_AMDSTD is not set
# CONFIG_MTD_CFI_STAA is not set
# CONFIG_MTD_RAM is not set
CONFIG_MTD_ROM=y
# CONFIG_MTD_ABSENT is not set
# CONFIG_MTD_OBSOLETE_CHIPS is not set
--------------------------------------

Since in xconfig, it has Intel/Sharp in the option together and my chips
have Sharp printed on it, I guess
it's right. Also, I referenced the .config file from Christian, who made
JFFS2 work for 2.4.4 (from denx) and
some older version of mtd, so I think the setup is ok.

Before I chase the source of the crashed trace, I want to look at something
I had to change to make it
compile, now seems to co-relate with my crash. I had to change mtdpart.c's
part_unpoint() to make
unpoint() only pass two parameters because mtd_info structure dictates it,
but in cfi_cmdset_0001.c,
the do_unpoint, which has four params, is assigned to unpoint func ptr
(warning in compile). It looks wrong
to me, and all those files are sym-linked from mtd-20021022 snapshot, can
you guys verify it's really
an inconsistancy, not my mistake?

When I stress test JFFS2 subsystem from 2.4.19 kernel, it seems to me it
always crashs at the beginning
of the 2nd cycle. I have a 7M JFFS2, and I copy 3M stuff on it, remove it,
and do it again, it always fails at
the 4th time, which, onsidering zlib compression on binary files, seems to
be the next cycle.

I will later provide the oops with the source lines.

Thanks a lot

- Junping

> -----Original Message-----
> From:	Jörn Engel [SMTP:joern at wohnheim.fh-wedel.de]
> Sent:	Tuesday, November 05, 2002 4:09 PM
> To:	Junping Zhang
> Cc:	linux-mtd at lists.infradead.org
> Subject:	Re: seeking help on JFFS2
> 
> On Tue, 5 November 2002 14:56:56 -0500, Junping Zhang wrote:
> > 
> >    I just tested 2.4.19 with shared-zlib patch, same behavior. I could
> use
> > the JFFS2 system,
> > but it will eventually crash after a while.
> > 
> >    The flash chip is original from Motorola: 8M, 80 pin SIMM, SM73228. I
> > used Christian's
> > map file. Since JFFS works on it without any problem, should I safely
> assume
> > the MTD layer
> > is correct?
> 
> Ok, glancing at the spec, it said something about being compatible to
> Am29F040 chips, which use the amd command set. And looking back at the
> trace, we see
>     Trace; c00df668 <cfi_intelext_read+b4/100>
>                          ^^^^^
> This is strange.
> 
> Have you configured only CONFIG_MTD_CFI_AMDSTD, only
> CONFIG_MTD_CFI_INTELEXT or both?
> 
> Jörn
> 
> -- 
> The competent programmer is fully aware of the strictly limited size of
> his own skull; therefore he approaches the programming task in full
> humility, and among other things he avoids clever tricks like the plague. 
> -- Edsger W. Dijkstra