[Yaffs] Files gone after power cycle.

Hi,

I have a device with kernel 2.6.36.
I am able to mount a yaffs file system and it appears to work.
However, the files are gone after power cycle.
What is the best way to diagnose this problem?
Any hints are greatly appreciated.

--pawel

# grep YAFFS .config
CONFIG_YAFFS_FS=y
CONFIG_YAFFS_YAFFS1=y
# CONFIG_YAFFS_9BYTE_TAGS is not set
# CONFIG_YAFFS_DOES_ECC is not set
CONFIG_YAFFS_YAFFS2=y
CONFIG_YAFFS_AUTO_YAFFS2=y
# CONFIG_YAFFS_DISABLE_TAGS_ECC is not set
# CONFIG_YAFFS_DISABLE_WIDE_TNODES is not set
# CONFIG_YAFFS_ALWAYS_CHECK_CHUNK_ERASED is not set
CONFIG_YAFFS_SHORT_NAMES_IN_RAM=y
# CONFIG_YAFFS_EMPTY_LOST_AND_FOUND is not set
# CONFIG_YAFFS_DISABLE_BLOCK_REFRESHING is not set
# CONFIG_YAFFS_DISABLE_BACKGROUND is not set
CONFIG_YAFFS_XATTR=y

# ps | grep yaffs
94 0            0 SW   [yaffs-bg-1]

# dmesgs
...
yaffs: dev is 32505862 name is "mtdblock6" rw
yaffs: passed flags ""
yaffs: Attempting MTD mount of 31.6,"mtdblock6"
yaffs_read_super: is_checkpointed 0

# cat /proc/yaffs
Multi-version YAFFS built:Jun 8 2015 09:08:54


Device 0 "Overlay"
start_block.......... 0
end_block............ 665
total_bytes_per_chunk 2048
use_nand_ecc......... 1
no_tags_ecc.......... 0
is_yaffs2............ 1
inband_tags.......... 0
empty_lost_n_found... 0
disable_lazy_load.... 0
refresh_period....... 500
n_caches............. 10
n_reserved_blocks.... 5
always_check_erased.. 0

data_bytes_per_chunk. 2048
chunk_grp_bits....... 0
chunk_grp_size....... 1
n_erased_blocks...... 623
blocks_in_checkpt.... 0

n_tnodes............. 199
n_obj................ 69
n_free_chunks........ 39969

n_page_writes........ 4220
n_page_reads......... 1757
n_erasures........... 24
n_gc_copies.......... 1466
all_gcs.............. 301
passive_gc_count..... 301
oldest_dirty_gc_count 0
n_gc_blocks.......... 24
bg_gcs............... 24
n_retired_writes..... 0
nRetireBlocks........ 0
n_ecc_fixed.......... 0
n_ecc_unfixed........ 0
n_tags_ecc_fixed..... 0
n_tags_ecc_unfixed... 0
cache_hits........... 0
n_deleted_files...... 0
n_unlinked_files..... 0
refresh_count........ 1
n_bg_deletions....... 0