https://bugzilla.novell.com/show_bug.cgi?id=823376 https://bugzilla.novell.com/show_bug.cgi?id=823376#c0 Summary: SUSE Xen Server does not appear to forward packets properly when the GRO is enabled. Classification: openSUSE Product: openSUSE 11.4 Version: Factory Platform: x86-64 OS/Version: openSUSE 11.2 Status: NEW Severity: Normal Priority: P5 - None Component: Xen AssignedTo: jdouglas@suse.com ReportedBy: rcnagara@brocade.com QAContact: qa-bugs@suse.de Found By: --- Blocker: --- User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/27.0.1453.94 Safari/537.36 SUSE Xen Server is not forwarding packets properly when the GRO is enabled. Configuration: Create a bridge on physical interface which does GRO, from xen server. Add a virtual network interface on to this bridge to a VM running linux. # uname -r 3.0.13-0.27-xen # rpm -qa | grep xen xen-tools-4.1.2_14-0.5.5 kernel-xen-3.0.13-0.27.1 kernel-xen-base-3.0.13-0.27.1 kernel-xen-devel-3.0.13-0.27.1 xen-4.1.2_14-0.5.5 xen-libs-4.1.2_14-0.5.5 # brctl show bridge name bridge id STP enabled interfaces br0 8000.6cae8b223762 no eth0 vif10.0 br1 8000.6eae8b223761 no usb0 br2 8000.8c7cff352002 no eth4 << Physical interface with GRO enabled. vif10.1 << VM's interface. vif10.2 Run ping from VM to an external host. It will result in 95% packet loss. Looking at the tcpdump, eth4 sends out ICMP requests & receives the ICMP reponse. But the 'br2' interface does not 95% of those packets. With GRO enabled the driver is properly handing over packets to the kernel via napi_gro_frags(). But 'br2' is not receiving it. If the IP address is configured on eth4 directly and is removed from bridge 'br2', there won't be any packet drops with GRO enabled. The problem disappears if the GRO disabled on the physical interface. In that case, the driver uses netif_receive_skb() to handover packets to the kernel. The VM receives all packets and there will be no packet loss. Question: Is there a known issue with SUSE Xen server bridging when the GRO is enabled OR does it need any configuration to enable proper bridging ? Reproducible: Always Steps to Reproduce: Provided in 'Details' section above. Actual Results: 95% of the packets are dropped. Expected Results: There should not be any packet drops. This may not be issue, if there is only related to configuration. In such a case, please consider this as a query and suggest. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.