System Settings: Linux kernel version - 2.6.23.12 NAND FLASH chip - Samsung 2GiB MLC K9LAG08 The NAND FLASH is used as root file system with Debian Etch for AMR distribution. Error(warning) messages: The partial written block and set to retired message similar to the following always appear when reboot, Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement Partially written block 975 being set for retirement **>> Block 975 retired However do a cat /proc/yaffs shows no block is retired, YAFFS built:Dec 27 2007 08:12:30 $Id: yaffs_fs.c,v 1.65 2007-12-13 15:35:17 wookey Exp $ $Id: yaffs_guts.c,v 1.54 2007-12-13 15:35:17 wookey Exp $ Device 0 "GESBC NAND FLASH" startBlock......... 0 endBlock........... 8191 nDataBytesPerChunk. 2048 chunkGroupBits..... 0 chunkGroupSize..... 1 nErasedBlocks...... 6388 nReservedBlocks.... 5 blocksInCheckpoint. 0 nTnodesCreated..... 19100 nFreeTnodes........ 696 nObjectsCreated.... 15000 nFreeObjects....... 18 nFreeChunks........ 930337 nPageWrites........ 0 nPageReads......... 0 nBlockErasures..... 0 nGCCopies.......... 0 garbageCollections. 0 passiveGCs......... 0 nRetriedWrites..... 0 nShortOpCaches..... 10 nRetireBlocks...... 0 eccFixed........... 0 eccUnfixed......... 0 tagsEccFixed....... 0 tagsEccUnfixed..... 0 cacheHits.......... 389 nDeletedFiles...... 3130 nUnlinkedFiles..... 3176 nBackgroudDeletions 0 useNANDECC......... 1 isYaffs2........... 1 If the NAND FLASH is mounted as part of the file system but not the root, there doesn't seem to be any of these kinds of messages. The question is if those error (warning) messages serious. What would be cause of those messages? Thanks, zl