Re: [PATCH] x86: fix memory cut-off when using PFN compression

[Keir Fraser <keir.xen@gmail.com>]

On 11/09/2013 05:48, "Jan Beulich" <JBeulich@suse.com> wrote:

> For one setup_max_pdx(), when invoked a second time (after SRAT got
> parsed), needs to start from the original max_page value again (using
> the already adjusted one from the first invocation would not allow the
> cut-off boundary to be moved up).
> 
> Second, _if_ we need to cut off some part of memory, we must not allow
> this to also propagate into the NUMA accounting. Otherwise
> cutoff_node() results in nodes_cover_memory() to find some parts of
> memory apparently not having a PXM association, causing all SRAT info
> to be ignored.
> 
> The only possibly problematic consumer of node_spanned_pages (the
> meaning of which gets altered here in that it now also includes memory
> Xen can't actively make use of) is XEN_SYSCTL_numainfo: At a first
> glance the potentially larger reported memory size shouldn't confuse
> tool stacks.
> 
> And finally we must not put our boot time modules at addresses which
> (at that time) can't be guaranteed to be accessible later. This applies
> to both the EFI boot loader and the module relocation code.
> 
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Acked-by: Keir Fraser <keir@xen.org>