Re: A patch to loop.c for better cryption support

From: Andi Kleen (
Date: Fri Oct 13 2000 - 12:37:59 EST

On Fri, Oct 13, 2000 at 05:04:08PM +0000, Marc Mutz wrote:
> Andi Kleen wrote:
> >
> <snip>
> > 2.4 has already broken backwards compatibility to 2.2 (IV changed
> > from disk absolute to relative). When you change it now (before 2.4.0)
> > it is relatively painless. I think the change is a good idea.
> <snip>
> You're wrong. All kernels from int- onwards can be configured to
> use relative block numbers as IV's. Both the FAQ in Documentation/crypto
> and my HOWTO suggest to set CONFIG_BLK_DEV_LOOP_USE_REL_BLOCK to 'y'.

That is not a standard kernel option. I'm not talking about any unofficial
patchkits like the i* patches, just about what the standard loop device does.
An encryption module can be backwards compatible itself by mapping the blocks
itself, but without changes it will have an incompatible on disk format.


To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
Please read the FAQ at

This archive was generated by hypermail 2b29 : Sun Oct 15 2000 - 21:00:25 EST