If num_ballooned is not 0, we shouldn't neglect the already-partially-allocated 2MB memory block(s). Cc: Jason Wang <jasowang@xxxxxxxxxx> Cc: K. Y. Srinivasan <kys@xxxxxxxxxxxxx> Signed-off-by: Dexuan Cui <decui@xxxxxxxxxxxxx> --- v2: I fixed the logic error in v1, pointed by Jason Wang: In v1: in the case of partially-allocated 2MB, alloc_error is true, so we'll run "done = true" and hence we won't proceed with the next iteration of trying 4K allocation. I also changed the WARN_ON to WARN_ON_ONCE in case the host behavior changes in the future. drivers/hv/hv_balloon.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c index 5e90c5d..b958ded 100644 --- a/drivers/hv/hv_balloon.c +++ b/drivers/hv/hv_balloon.c @@ -1087,10 +1087,12 @@ static void balloon_up(struct work_struct *dummy) struct dm_balloon_response *bl_resp; int alloc_unit; int ret; - bool alloc_error = false; + bool alloc_error; bool done = false; int i; + /* The host balloons pages in 2M granularity. */ + WARN_ON_ONCE(num_pages % PAGES_IN_2M != 0); /* * We will attempt 2M allocations. However, if we fail to @@ -1107,16 +1109,18 @@ static void balloon_up(struct work_struct *dummy) num_pages -= num_ballooned; + alloc_error = false; num_ballooned = alloc_balloon_pages(&dm_device, num_pages, bl_resp, alloc_unit, &alloc_error); - if ((alloc_error) && (alloc_unit != 1)) { + if (alloc_unit != 1 && num_ballooned == 0) { alloc_unit = 1; continue; } - if ((alloc_error) || (num_ballooned == num_pages)) { + if ((alloc_unit == 1 && alloc_error) || + (num_ballooned == num_pages)) { bl_resp->more_pages = 0; done = true; dm_device.state = DM_INITIALIZED; -- 1.9.1 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel