1 files changed, 13 insertions, 3 deletions

diff --git a/drivers/xen/balloon.c b/drivers/xen/balloon.c
index 37a36c6b9f93..4e11de6cde81 100644
--- a/drivers/xen/balloon.c
+++ b/drivers/xen/balloon.c
@@ -535,8 +535,15 @@ static void balloon_process(struct work_struct *work)
                                 state = reserve_additional_memory();
                 }
 
-                if (credit < 0)
-                        state = decrease_reservation(-credit, GFP_BALLOON);
+                if (credit < 0) {
+                        long n_pages;
+
+                        n_pages = min(-credit, si_mem_available());
+                        state = decrease_reservation(n_pages, GFP_BALLOON);
+                        if (state == BP_DONE && n_pages != -credit &&
+                            n_pages < totalreserve_pages)
+                                state = BP_EAGAIN;
+                }
 
                 state = update_schedule(state);
 
@@ -575,6 +582,9 @@ static int add_ballooned_pages(int nr_pages)
                 }
         }
 
+        if (si_mem_available() < nr_pages)
+                return -ENOMEM;
+
         st = decrease_reservation(nr_pages, GFP_USER);
         if (st != BP_DONE)
                 return -ENOMEM;
@@ -707,7 +717,7 @@ static int __init balloon_init(void)
         balloon_stats.schedule_delay = 1;
         balloon_stats.max_schedule_delay = 32;
         balloon_stats.retry_count = 1;
-        balloon_stats.max_retry_count = RETRY_UNLIMITED;
+        balloon_stats.max_retry_count = 4;
 
 #ifdef CONFIG_XEN_BALLOON_MEMORY_HOTPLUG
         set_online_page_callback(&xen_online_page);