* Re: [PATCH V2 1/2] Drivers: hv: balloon: Fix a bug in the hot-add code
2013-07-15 5:38 ` [PATCH V2 1/2] Drivers: hv: balloon: Fix a bug in the hot-add code K. Y. Srinivasan
@ 2013-07-15 5:05 ` Jason Wang
2013-07-15 5:38 ` [PATCH V2 2/2] Drivers: hv: balloon: Do not post pressure status if interrupted K. Y. Srinivasan
1 sibling, 0 replies; 3+ messages in thread
From: Jason Wang @ 2013-07-15 5:05 UTC (permalink / raw)
To: K. Y. Srinivasan; +Cc: gregkh, linux-kernel, devel, olaf, apw, Stable
On 07/15/2013 01:38 PM, K. Y. Srinivasan wrote:
> As we hot-add 128 MB chunks of memory, we wait to ensure that the memory
> is onlined before attempting to hot-add the next chunk. If the udev rule for
> memory hot-add is not executed within the allowed time, we would rollback the
> state and abort further hot-add. Since the hot-add has succeeded and the only
> failure is that the memory is not onlined within the allowed time, we should not
> be rolling back the state. Fix this bug.
>
> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
> Cc: Stable <stable@vger.kernel.org>
> ---
> drivers/hv/hv_balloon.c | 13 +++++--------
> 1 files changed, 5 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
> index 4c605c7..61b7351 100644
> --- a/drivers/hv/hv_balloon.c
> +++ b/drivers/hv/hv_balloon.c
> @@ -562,7 +562,7 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size,
> struct hv_hotadd_state *has)
> {
> int ret = 0;
> - int i, nid, t;
> + int i, nid;
> unsigned long start_pfn;
> unsigned long processed_pfn;
> unsigned long total_pfn = pfn_count;
> @@ -607,14 +607,11 @@ static void hv_mem_hot_add(unsigned long start, unsigned long size,
>
> /*
> * Wait for the memory block to be onlined.
> + * Since the hot add has succeeded, it is ok to
> + * proceed even if the pages in the hot added region
> + * have not been "onlined" within the allowed time.
> */
> - t = wait_for_completion_timeout(&dm_device.ol_waitevent, 5*HZ);
> - if (t == 0) {
> - pr_info("hot_add memory timedout\n");
> - has->ha_end_pfn -= HA_CHUNK;
> - has->covered_end_pfn -= processed_pfn;
> - break;
> - }
> + wait_for_completion_timeout(&dm_device.ol_waitevent, 5*HZ);
>
> }
>
Acked-by: Jason Wang <jasowang@redhat.com>
Thanks
^ permalink raw reply [flat|nested] 3+ messages in thread* [PATCH V2 2/2] Drivers: hv: balloon: Do not post pressure status if interrupted
2013-07-15 5:38 ` [PATCH V2 1/2] Drivers: hv: balloon: Fix a bug in the hot-add code K. Y. Srinivasan
2013-07-15 5:05 ` Jason Wang
@ 2013-07-15 5:38 ` K. Y. Srinivasan
1 sibling, 0 replies; 3+ messages in thread
From: K. Y. Srinivasan @ 2013-07-15 5:38 UTC (permalink / raw)
To: gregkh, linux-kernel, devel, olaf, apw, jasowang; +Cc: K. Y. Srinivasan, Stable
When we are posting pressure status, we may get interrupted and handle
the un-balloon operation. In this case just don't post the status as we
know the pressure status is stale.
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Cc: Stable <stable@vger.kernel.org>
---
drivers/hv/hv_balloon.c | 8 ++++++++
1 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/drivers/hv/hv_balloon.c b/drivers/hv/hv_balloon.c
index 61b7351..deb5c25 100644
--- a/drivers/hv/hv_balloon.c
+++ b/drivers/hv/hv_balloon.c
@@ -975,6 +975,14 @@ static void post_status(struct hv_dynmem_device *dm)
dm->num_pages_ballooned +
compute_balloon_floor();
+ /*
+ * If our transaction ID is no longer current, just don't
+ * send the status. This can happen if we were interrupted
+ * after we picked our transaction ID.
+ */
+ if (status.hdr.trans_id != atomic_read(&trans_id))
+ return;
+
vmbus_sendpacket(dm->dev->channel, &status,
sizeof(struct dm_status),
(unsigned long)NULL,
--
1.7.4.1
^ permalink raw reply related [flat|nested] 3+ messages in thread