[Yaffs] Re: [YAFFS1] Some bits are changed - systematically

[Martin Egholm Nielsen]

Hello again,

 > I'm sure Charles will ask for this when he wakes up in New
 > Zealand... and you go to sleep... can you post the complete
 > output from /proc/yaffs and say which platform (eg, PPC, ARM)
 > which kernel, which MTD. Your problem looks intriguing.

 >>Compare error at OFFSET 132010 (-132013)
 >>Correct: 00 00 03 A4
 >>Altered: 0F F8 4F D4
 >>
 >>Compare error at OFFSET 132048 (-13204B)
 >>Correct: 00 00 08 A4
 >>Altered: 0F F8 54 D4
 >>
 >>Compare error at OFFSET 13206C (-13206D)
 >>Correct: 00 00
 >>Altered: 0F F8

Sure... But I f*cked up, because I "overwrote" the "faulty" libc with a 
new version to solve the problem! I thought we really needed a working 
device to get further, but we settled without, so it's still here on my 
desk, with the bad libc in the flash but with old "inodes" (I guess)...

If it comes to it, I guess it is possible to create a special kernel and 
yaffs-fs implementation, that removes the newly written libc-file, to 
restore the old state. Although I reckon this requires quite the works ;-(

Specs and info:
---------------
* PPC405EP.

* 32 Megs SAMSUNG NAND device.

* Linux 2.4.20 patched with:

* MTD from CVS head 2005-07-22 - manually patched in using last 
officially working MTD for 2.4 as reference.

* "Many" (20-100) big (~8megs) flash writes (causing crossing of 
flash-end boundary a couple of times, I guess) before problem occurred.

* /proc/yaffs given below - but of course this is for the fs after 
overwriting the faulty libc (stupid me!). But as I recalled it, it was 
similar - but what do I know!

# cat /proc/yaffs
YAFFS built:Aug  1 2005 10:37:33
$Id: yaffs_fs.c,v 1.40 2005/06/25 03:22:23 charles Exp $
$Id: yaffs_guts.c,v 1.42 2005/06/25 03:22:23 charles Exp $

Device yaffs
startBlock......... 0
endBlock........... 2047
chunkGroupBits..... 1
chunkGroupSize..... 2
nErasedBlocks...... 395
nTnodesCreated..... 4100
nFreeTnodes........ 39
nObjectsCreated.... 1200
nFreeObjects....... 97
nFreeChunks........ 16493
nPageWrites........ 147
nPageReads......... 71678
nBlockErasures..... 3
nGCCopies.......... 2
garbageCollections. 2
passiveGCs......... 2
nRetriedWrites..... 0
nRetireBlocks...... 0
eccFixed........... 0
eccUnfixed......... 0
tagsEccFixed....... 0
tagsEccUnfixed..... 395
cacheHits.......... 114
nDeletedFiles...... 84
nUnlinkedFiles..... 84
nBackgroudDeletions 0
useNANDECC......... 1
nShortOpCaches..... 10


BR,
  Martin Egholm