[dm-devel] Re: dm-ioctl on amd64 with 32bit userspace

[Alasdair G Kergon]

On Wed, Sep 19, 2007 at 05:26:50PM -0700, Andrew Morton wrote:
> I don't understand why people aren't running around with their hair on fire
> over this bug.    Is everyone running 64-bit dmsetup, or what?
 
1) There probably aren't many users in a mixed 32/64 environment;
2) The operations triggering the problem are fairly uncommon.

It's still a surprise nobody noticed this before (with lvrename) as it looks
like this has always been broken.

This particular patch looks inadequate though - fixes it for some people
but breaks it for others?  Other parts of this code call alignment
functions and store offsets explicitly and probably something similar
should be happening here - with userspace libdevmapper changes too.
Let me consider the alternatives and their consequences.

> This looks like 2.6.22 and 2.6.23 material to me.  Alasdair?

When we have a complete fix, yes.

Alasdair
-- 
agk at redhat.com