In order to avoid problematic special linking of the Launcher, we give
the Host an offset: this means we can use any memory region in the
Launcher as Guest memory rather than insisting on mmap() at 0.
The result is quite pleasing: a number of casts are replaced with
simple additions.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
lguest_launcher.h uses "u32" not "__u32", which sets a bad example. Fix that,
and include <linux/types.h>.
This means we need to use -I on the Launcher build line so types.h is found.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Some versions of ld.so mmap the shared libraries right in over guest
memory, so compile lguest statically by default.
[ FC7 maps shared libraries very low, where the launcher maps guest's
physical memory. Quick fix is to link Launcher static, real fix is
for 2.6.24. ]
-static is a simple fix. I expect this problem will be more common than we
like, as different distro's make different "improvements" to ld.so
Signed-off-by: Ronald G. Minnich <rminnich@gmail.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
S.Caglar Onur points out that many distributions don't ship a static
zlib. Unfortunately the launcher currently maps virtual device memory
where shared libraries want to go.
The solution is to pre-scan the args to figure out how much memory we
have, then allocate devices above that, rather than down from the top
possible address. This also turns out to be simpler.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A brief document describing how to use lguest. Because lguest doesn't have an
ABI we also include an example launcher in the Documentation directory.
[jmorris@namei.org: Fix up nat example in documentation]
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Andi Kleen <ak@suse.de>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Matias Zabaljauregui <matias.zabaljauregui@cern.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Rusty Russell
Ronald G. Minnich