If num_ballooned is not 0, we shouldn't neglect the
already-partially-allocated 2MB memory block(s).
Cc: Jason Wang <[email protected]>
Cc: K. Y. Srinivasan <[email protected]>
Signed-off-by: Dexuan Cui <[email protected]>
---
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
On 11/25/2014 12:32 PM, Dexuan Cui wrote:
> If num_ballooned is not 0, we shouldn't neglect the
> already-partially-allocated 2MB memory block(s).
>
> Cc: Jason Wang <[email protected]>
> Cc: K. Y. Srinivasan <[email protected]>
> Signed-off-by: Dexuan Cui <[email protected]>
> ---
>
> 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;
Acked-by: Jason Wang <[email protected]>
Thanks
> -----Original Message-----
> From: Dexuan Cui [mailto:[email protected]]
> Sent: Monday, November 24, 2014 8:33 PM
> To: [email protected]; [email protected]; driverdev-
> [email protected]; [email protected]; [email protected];
> [email protected]; KY Srinivasan
> Cc: Haiyang Zhang
> Subject: [PATCH v2] hv: hv_balloon: avoid memory leak on alloc_error of
> 2MB memory block
>
> If num_ballooned is not 0, we shouldn't neglect the already-partially-
> allocated 2MB memory block(s).
>
> Cc: Jason Wang <[email protected]>
> Cc: K. Y. Srinivasan <[email protected]>
> Signed-off-by: Dexuan Cui <[email protected]>
Signed-off-by: K. Y. Srinivasan <[email protected]>
> ---
>
> 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