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Anyone know what happens when UBI uses up all its reserved PEBs that are reserved for bad block management? For example say I have a UBI volume that has 14 PEBs reserved

# ubinfo -d 1  
Volumes count:                           1
Logical eraseblock size:                 126976 bytes, 124.0 KiB
Total amount of logical eraseblocks:     1466 (186146816 bytes, 177.5 MiB)
Amount of available logical eraseblocks: 787 (99930112 bytes, 95.3 MiB)
Maximum count of volumes                 128
Count of bad physical eraseblocks:       0
Count of reserved physical eraseblocks:  14
Current maximum erase counter value:     9
Minimum input/output unit size:          2048 bytes
Character device major/minor:            249:0
Present volumes:                         0

What happens when UBI finds bad block number 15? Does it not allow the volumes to be used?

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up vote 1 down vote accepted

I've tested it on armv5tel GNU/Linux 2.6.39+ by marking physical eraseblocks (PEB) as bad using the U-Boot command line:

When the bad PEB count is higher than the amount of reserved PEBs, the volume will still be usable. As long as free blocks are available they are used to replace the bad ones. Problems will occur when all PEBs are used up and a new bad block is discovered.

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