JFFS2 file system slowly filling up for unknown reason ~20 seconds after mount

I'm currently working on a Linux project with a Philips LPC3180 based system. The Linux support for this board seems to be under development by Philips and is not yet in the main Linux tree (we received support as a patch). So this problem could very well be related to the drivers we received for this platform, but I wanted to check if anyone else has experienced similar behavior or have any pointers as to the cause.

Description of problem:

After mounting jffs2 file system it gradually goes from 45% full to 100% in the matter of ~20 seconds (as reported by df). Doing a du on the top directory of the file system shows the same amount of data as when it is first mounted. Unmounting and remounting still shows 100% usage, and no files can be written (device full). Rebooting and then remounting the file system, then goes through the 45% to 100% gradual fill up again. No kernel error messages are received when mounting or unmounting. The actual jffs2 image file which gets flashed is ~3MB and contains ~6MB of data (which gets zlib compressed as shown by mkfs.jffs2 -v). The flash partition is ~10MB.

I was able to successfully flash other parts of the flash memory (the first partition) with kernel, uboot, etc. So I'm pretty sure that is working correctly, and the files in the jffs2 file system are indeed there after mounting.

Details of system:

Linux kernel 2.6.10 with patch from Philips Cross compiler gcc 3.4.2 using scratchbox
Flash is an ST Micro NAND256R3A 32MB chip with 8 bit bus

MTD messages on boot, showing the 2 partitions I created. The erase block size is 0x4000 (16KiB), as reported by /proc/mtd.

NAND device: Manufacturer ID: 0x20, Chip ID: 0x35 (ST Micro NAND 32MiB 1,8V 8-bit) Scanning device for bad blocks
Creating 2 MTD partitions on "NAND 32MiB 1,8V 8-bit":
0x00008000-0x00c00000 : "rootfs-kernel-uboot"
0x00c00000-0x01640000 : "jffs2"

jffs2 file system created with the following command:
mkfs.jffs2 -n -e 16384 -o rootfs_jffs2.img -r target

Flashed with the following commands on the target:
flash_erase /dev/mtdchar1 0 656
nandwrite -p -s 0 /dev/mtdchar1 rootfs_jffs2.img

df immediately after mount and ~20 seconds later (going gradually upwards).

Filesystem 1k-blocks Used Available Use% Mounted on
/dev/mtdblock1 10496 4672 5824 45% /mnt/disk

Filesystem 1k-blocks Used Available Use% Mounted on
/dev/mtdblock1 10496 10496 0 100% /mnt/disk

If anyone has any helpful information they could share in regards to this problem, I would appreciate it. This could very well be a jffs2 specific problem, but the jffs list seems rather dead, and there is a lot related to jffs2 on this list. Please let me know if I'm posting to the wrong list though.

Best regards,
Josh Green

Hi,

I have never heard of such a really weird problem.

Ancient kernel, not a lot of people are interested in digging it.

It's the right list.

Best regards,
Artem Bityutskiy (Битюцкий Артём)

Absolutely, especially given the possible side effects of the "patch from Philips" no one here has actually seen ;-)
What I'd suggest is to try quickporting the board support and flash driver to the latest community kernel and reproducing the problem with this new setup.

Vitaly