UBI/UBIFS issue: corrupt empty space => switched to read-only mode

[Matteo Mattei]

Hi guys,

I am working hard on UBIFS to make it works on 2.6.32 and OMAP3530.

I already posted some requests to TI forum but I have no answers up to now:
http://e2e.ti.com/support/embedded/linux/f/354/t/171839.aspx#627875

The error I get is this:

UBI: attaching mtd6 to ubi0
UBI: physical eraseblock size: 131072 bytes (128 KiB)
UBI: logical eraseblock size: 126976 bytes
UBI: smallest flash I/O unit: 2048
UBI: VID header offset: 2048 (aligned 2048)
UBI: data offset: 4096
UBI: max. sequence number: 1621513
UBI: attached mtd6 to ubi0
UBI: MTD device name: "FileSystem"
UBI: MTD device size: 847 MiB
UBI: number of good PEBs: 6769
UBI: number of bad PEBs: 7
UBI: number of corrupted PEBs: 0
UBI: max. allowed volumes: 128
UBI: wear-leveling threshold: 4096
UBI: number of internal volumes: 1
UBI: number of user volumes: 1
UBI: available PEBs: 0
UBI: total number of reserved PEBs: 6769
UBI: number of PEBs reserved for bad PEB handling: 134
UBI: max/mean erase counter: 2417/239
UBI: image sequence number: 0
UBI: background thread "ubi_bgt0d" started, PID 587
UBIFS: recovery needed
UBIFS error (pid 590): ubifs_scan: corrupt empty space at LEB 997:116771
UBIFS error (pid 590): ubifs_scanned_corruption: corruption at LEB 997:116771
UBIFS error (pid 590): ubifs_scan: LEB 997 scanning failed
UBIFS error (pid 590): do_commit: commit failed, error -117
UBIFS warning (pid 590): ubifs_ro_mode: switched to read-only mode, error -117
UBIFS: recovery completed
UBIFS: mounted UBI device 0, volume 0, name "ROOTFS"
UBIFS: file system size: 839819264 bytes (820136 KiB, 800 MiB, 6614 LEBs)
UBIFS: journal size: 33521664 bytes (32736 KiB, 31 MiB, 264 LEBs)
UBIFS: media format: w4/r0 (latest is w4/r0)
UBIFS: default compressor: none
UBIFS: reserved for root: 4952683 bytes (4836 KiB)

I already saw that in kernel 3.2.x a similar problem has been reported.
Investigating I saw that the error occurred during the journal commit.

Do you have any hints where to investigate further or where to apply
some changes to the sources to fix this issue?
One more question, I saw that in scan.c of UBI driver the policy to
handle corrupted blocks is to distinguish between powercuts and other
reasons.
In the latter case the block is put in corrupted list and no more
recovered. A comment in the sources says that the block is left there
for manual inspection.
However my system is unattended... do you see anything bad to add also
this kind of blocks to the erase list?


Thanks,

Matteo