From 81da4016bfeb5bde06b79004bf5df8738259b1a3 Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Wed, 12 Sep 2012 10:19:34 +0200 Subject: x86-64/EFI: allow chaining of config files Namely when making use the CONFIG_XEN_COMPAT_* options in the legacy Linux kernels, newer kernels may not be compatible with older hypervisors, so trying to boot such a combination makes little sense. Booting older kernels on newer hypervisors, however, has to always work. With the way xen.efi looks for its configuration file, allowing individual configuration files to refer only to compatible kernels, and referring from an older- to a newer-hypervisor one (the kernels of which will, as said, necessarily be compatible with the older hypervisor) allows to greatly reduce redundancy at least in development environments where one frequently wants multiple hypervisors and kernles to be installed in parallel. Signed-off-by: Jan Beulich Acked-by: Keir Fraser --- docs/misc/efi.markdown | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'docs/misc') diff --git a/docs/misc/efi.markdown b/docs/misc/efi.markdown index d697bc23c8..19b987a848 100644 --- a/docs/misc/efi.markdown +++ b/docs/misc/efi.markdown @@ -75,6 +75,13 @@ Specifies an XSM module to load. Specifies a CPU microcode blob to load. +###`chain=` + +Specifies an alternate configuration file to use in case the specified section +(and in particular its `kernel=` setting) can't be found in the default (or +specified) configuration file. This is only meaningful in the [global] section +and really not meant to be used together with the `-cfg=` command line option. + Filenames must be specified relative to the location of the EFI binary. Extra options to be passed to Xen can also be specified on the command line, -- cgit v1.2.3