Due to a bug in the Hyper-V host verion 2008R2, we need to use a slightly smaller receive buffer size, otherwise the buffer will not be accepted by the legacy hosts. Without this fix, the network driver will not load while hosting Trusty on Server 2008R2. The following patch addresses the problem:
[PATCH net-next] hyperv: Change the receive buffer size for legacy hosts
Due to a bug in the Hyper-V host verion 2008R2, we need to use a slightly smaller
receive buffer size, otherwise the buffer will not be accepted by the legacy hosts.
Signed-off-by: Haiyang Zhang <email address hidden>
---
drivers/net/hyperv/hyperv_net.h | 1 +
drivers/net/hyperv/netvsc.c | 6 +++++-
2 files changed, 6 insertions(+), 1 deletions(-)
diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 39fc230..ea5f182 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -516,6 +516,7 @@ struct nvsp_message {
#define NETVSC_MTU 65536
#define NETVSC_RECEIVE_BUFFER_SIZE (1024*1024*16) /* 16MB */
+#define NETVSC_RECEIVE_BUFFER_SIZE_LEGACY (1024*1024*15) /* 15MB */
#define NETVSC_RECEIVE_BUFFER_ID 0xcafe
diff --git a/drivers/net/hyperv/netvsc.c b/drivers/net/hyperv/netvsc.c
index 1a0280d..daddea2 100644
--- a/drivers/net/hyperv/netvsc.c
+++ b/drivers/net/hyperv/netvsc.c
@@ -365,6 +365,11 @@ static int netvsc_connect_vsp(struct hv_device *device)
goto cleanup;
/* Post the big receive buffer to NetVSP */
+ if (net_device->nvsp_version <= NVSP_PROTOCOL_VERSION_2)
+ net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE_LEGACY;
+ else
+ net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
+
ret = netvsc_init_recv_buf(device);
cleanup:
@@ -898,7 +903,6 @@ int netvsc_device_add(struct hv_device *device, void *additional_info)
ndev = net_device->ndev;
/* Initialize the NetVSC channel extension */
- net_device->recv_buf_size = NETVSC_RECEIVE_BUFFER_SIZE;
spin_lock_init(&net_device->recv_pkt_list_lock);
INIT_LIST_HEAD(&net_device->recv_pkt_list);
--
1.7.4.1
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1290151
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.