Re: Some thoughts about providing data block checksumming for ext4

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




> > Recovery after a power fail
> > ---------------------------
> > 
> > If the dm-protected device was not cleanly shut down, then we need to
> > examine all of the checksum blocks in the Active Area.  For each
> > checksum block in the AA, the checksums for all of their data blocks
> > should machine either the checksum found in the AA, or the checksum
> > found in the checksum block in the checksum group.
> 
> ... and if the checksum of the block matches BOTH the checksum in the AA 
> and the checksum in the checksum group (because of checksum function 
> collision), you don't know which 4-bit nibble belongs to the data in the 
> block.

Though, I realize that you could avoid this problem by selecting the 
appropriate checksum function - that never results in collision if the 
4-bit nibble differs.

Mikulas

--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel




[Index of Archives]     [DM Crypt]     [Fedora Desktop]     [ATA RAID]     [Fedora Marketing]     [Fedora Packaging]     [Fedora SELinux]     [Yosemite Discussion]     [KDE Users]     [Fedora Docs]

  Powered by Linux