2 files changed, 31 insertions, 2 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 056d11faef21..8f3eea6b80c5 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -313,6 +313,17 @@ static void xen_align_and_add_e820_region(u64 start, u64 size, int type)
         e820_add_region(start, end - start, type);
 }
 
+void xen_ignore_unusable(struct e820entry *list, size_t map_size)
+{
+        struct e820entry *entry;
+        unsigned int i;
+
+        for (i = 0, entry = list; i < map_size; i++, entry++) {
+                if (entry->type == E820_UNUSABLE)
+                        entry->type = E820_RAM;
+        }
+}
+
 /**
  * machine_specific_memory_setup - Hook for machine specific memory setup.
  **/
@@ -353,6 +364,17 @@ char * __init xen_memory_setup(void)
         }
         BUG_ON(rc);
 
+        /*
+         * Xen won't allow a 1:1 mapping to be created to UNUSABLE
+         * regions, so if we're using the machine memory map leave the
+         * region as RAM as it is in the pseudo-physical map.
+         *
+         * UNUSABLE regions in domUs are not handled and will need
+         * a patch in the future.
+         */
+        if (xen_initial_domain())
+                xen_ignore_unusable(map, memmap.nr_entries);
+
         /* Make sure the Xen-supplied memory map is well-ordered. */
         sanitize_e820_map(map, memmap.nr_entries, &memmap.nr_entries);
 
diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c
index ca92754eb846..b81c88e51daa 100644
--- a/arch/x86/xen/smp.c
+++ b/arch/x86/xen/smp.c
@@ -694,8 +694,15 @@ static void __init xen_hvm_smp_prepare_cpus(unsigned int max_cpus)
 static int xen_hvm_cpu_up(unsigned int cpu, struct task_struct *tidle)
 {
         int rc;
-        rc = native_cpu_up(cpu, tidle);
-        WARN_ON (xen_smp_intr_init(cpu));
+        /*
+         * xen_smp_intr_init() needs to run before native_cpu_up()
+         * so that IPI vectors are set up on the booting CPU before
+         * it is marked online in native_cpu_up().
+        */
+        rc = xen_smp_intr_init(cpu);
+        WARN_ON(rc);
+        if (!rc)
+                rc =  native_cpu_up(cpu, tidle);
         return rc;
 }