tree 647697838711f4d7c51cb59a5b942af288820c73
parent fb5a8792e6e4ee7de7ae3e06d193ea5beaaececc
author David Woodhouse <dwmw@amazon.co.uk> 1556448732 +0300
committer Simon Horman <horms@verge.net.au> 1557906011 +0200

xen: Avoid overlapping segments in low memory

Unlike Linux which creates a full identity mapping, Xen only maps those
segments which are explicitly requested. Therefore, xen_kexec_load()
silently adds in a segment from zero to 1MiB to ensure that VGA memory
and other things are accessible.

However, this doesn't work when there are already segments to be loaded
under 1MiB, because the overlap causes Xen to reject the kexec_load.

Be more careful and just infill the ranges which are required instead
of naïvely adding a full 0-1MiB segment at the end of the list.

Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Signed-off-by: Simon Horman <horms@verge.net.au>