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 <kys@xxxxxxxxxxxxx> --- 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 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/devel