If memory hot-add fails with the error -EEXIST, then this is a permanent
failure. Notify the host this information, so the host will not attempt
hot-add again. If the failure were a transient failure, host will attempt
a hot-add after some delay.
Signed-off-by: K. Y. Srinivasan <k...@microsoft.com>
---
drivers/hv/hv_balloon.c | 17 +++++++++++++++--
1 files changed, 15 insertions(+), 2 deletions(-)
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 71655b4..d2ed673 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -583,6 +583,16 @@ static void hv_mem_hot_add(unsigned long start, unsigned
long size,
if (ret) {
pr_info("hot_add memory failed error is %d\n", ret);
+ if (ret == -EEXIST) {
+ /*
+ * This error indicates that the error
+ * is not a transient failure. This is the
+ * case where the guest's physical address map
+ * precludes hot adding memory. Stop all further
+ * memory hot-add.
+ */
+ do_hot_add = false;
+ }
has->ha_end_pfn -= HA_CHUNK;
has->covered_end_pfn -= processed_pfn;
break;
@@ -842,11 +852,14 @@ static void hot_add_req(struct work_struct *dummy)
rg_sz = region_size;
}
- resp.page_count = process_hot_add(pg_start, pfn_cnt,
- rg_start, rg_sz);
+ if (do_hot_add)
+ resp.page_count = process_hot_add(pg_start, pfn_cnt,
+ rg_start, rg_sz);
#endif
if (resp.page_count > 0)
resp.result = 1;
+ else if (!do_hot_add)
+ resp.result = 1;
else
resp.result = 0;
--
1.7.4.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
