Merge branch 'stable/bug.fixes' of git://oss.oracle.com/git/kwilk/xen

* 'stable/bug.fixes' of git://oss.oracle.com/git/kwilk/xen:
  xen/smp: Warn user why they keel over - nosmp or noapic and what to use instead.
  xen: x86_32: do not enable iterrupts when returning from exception in interrupt context
  xen: use maximum reservation to limit amount of usable RAM

1 files changed, 19 insertions, 0 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index df118a8..c3b8d44 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -184,6 +184,19 @@ static unsigned long __init xen_set_identity(const struct e820entry *list,
 					PFN_UP(start_pci), PFN_DOWN(last));
 	return identity;
 }
+
+static unsigned long __init xen_get_max_pages(void)
+{
+	unsigned long max_pages = MAX_DOMAIN_PAGES;
+	domid_t domid = DOMID_SELF;
+	int ret;
+
+	ret = HYPERVISOR_memory_op(XENMEM_maximum_reservation, &domid);
+	if (ret > 0)
+		max_pages = ret;
+	return min(max_pages, MAX_DOMAIN_PAGES);
+}
+
 /**
  * machine_specific_memory_setup - Hook for machine specific memory setup.
  **/
@@ -292,6 +305,12 @@ char * __init xen_memory_setup(void)
 
 	sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 
+	extra_limit = xen_get_max_pages();
+	if (extra_limit >= max_pfn)
+		extra_pages = extra_limit - max_pfn;
+	else
+		extra_pages = 0;
+
 	extra_pages += xen_return_unused_memory(xen_start_info->nr_pages, &e820);
 
 	/*