When the issue happens (it looks due to the layout of the struct somehow...), can you try the small workaround patch at https://patchwork.ozlabs.org/patch/518469/?
I paste it below: diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index 88a0069..7233790 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -132,7 +132,9 @@ static inline bool dev_xmit_complete(int rc) * used. */ -#if defined(CONFIG_WLAN) || IS_ENABLED(CONFIG_AX25) +#if IS_ENABLED(CONFIG_HYPERV_NET) +# define LL_MAX_HEADER 224 +#elif defined(CONFIG_WLAN) || IS_ENABLED(CONFIG_AX25) # if defined(CONFIG_MAC80211_MESH) # define LL_MAX_HEADER 128 # else If this can work, please use the formal fixes from KY, which have been in linux-next: https://git.kernel.org/cgit/linux/kernel/git/next/linux-next.git/log/?qt=grep&q=hv_netvsc (please check the patches of the past week) -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1521053 Title: Network Performance dropping between vms on different location in Azure Status in linux package in Ubuntu: Invalid Status in linux source package in Vivid: In Progress Bug description: [Impact] Ubuntu VMs between different location in Azure , especially North Europe and East Europe in this case, have network performance issue. It should be around 100MB/s speed between them. but it's around 0.3MB/s when dropping happens. [Fix] Upstream development 0d158852a8089099a6959ae235b20f230871982f ("hv_netvsc: Clean up two unused variables") It's affected over 3.19.0-28-generic (ubuntu-vivid) [Testcase] Make 2 VMs on North Europe, West Europe each. Then run below test script NE VM - netcat & nload while true; do netcat -l 8080 < /dev/zero; done; nload -u M eth0 ( need nload pkg ) - iperf iperf -s -f M WE VM - netcat for i in {1..1000} do timeout 30s nc NE_HOST 8080 > /dev/null done - iperf iperf -c HOST -f M Network performance dropping can be seen frequently. More Tests http://pastebin.ubuntu.com/13657083/ To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1521053/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
