Bug 842999

Summary:	[virtio-win][netkvm] Package length with SSH protocol always <=1514 on WinXP when keeping netkvm parameters "TestOnly.Scatter-Gather" and "Offload Tx LSO" as default value "enable"
Product:	Red Hat Enterprise Linux 6	Reporter:	dawu
Component:	virtio-win	Assignee:	Yvugenfi <yvugenfi>
Status:	CLOSED WONTFIX	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	low	Docs Contact:
Priority:	low
Version:	6.4	CC:	acathrow, bcao, bsarathy, dyasny, michen, rhod, yvugenfi
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2012-07-29 11:03:48 UTC	Type:	Bug
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:

Description dawu 2012-07-25 09:13:40 UTC

Description of problem:
 Package length with SSH protocol always <=1514 on WinXP when keeping netkvm parameters "TestOnly.Scatter-Gather" and "Offload Tx LSO" as default value "enable", for other platforms, can find packages with length >=1514.

Version-Release number of selected component (if applicable):
kernel-2.6.32-279.el6.x86_64
qemu-kvm-0.12.1.2-2.295.el6.x86_64
virtio-win-1.5.3


How reproducible:
always

Steps to Reproduce:
1. Start guest with CLI:
   /usr/libexec/qemu-kvm -m 2G -smp 2 -cpu cpu64-rhel6,+x2apic,family=0xf -usb -device usb-tablet -drive file=winxp.qcow2,format=qcow2,if=none,id=drive-ide0-0-0,werror=stop,rerror=stop,cache=none -device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0,bootindex=1 -netdev tap,sndbuf=0,id=hostnet0,script=/etc/qemu-ifup,downscript=no -device virtio-net-pci,netdev=hostnet0,mac=90:10:1a:75:50:03,bus=pci.0,addr=0x4,id=virtio-net-pci0 -uuid a732b192-db0f-4130-9fb7-5317e4c98c7e -rtc base=localtime -no-kvm-pit-reinjection -chardev socket,id=111a,path=/tmp/winxp,server,nowait -mon chardev=111a,mode=readline -name xp-rhel63 -vnc :1 -monitor stdio

2. Set  "TestOnly.Scatter-Gather" and "Offload Tx LSO" to enable, and keep MTU size as default 1500

3. in guest, use winscp to scp file from guest to host ,at the same time ,open wireshark to listenning the package.

Actually result:
   Can not find any package with SSH protocol which length is >= 1514 on winxp
 
Expect Result:
   Length of some package wih SSH protocol should be >=1514
 
Additional info:
 1.This issue only reproduce on winxp, can not hit this issue on other guests (win2k8/win2k8-R2/win7/win2k3)
 2.Also tried with netperf, this issue also exist on winxp, the package length with TCP protocol still always <= 1514, but for other guest like win2k8-64, can found package with TCP protocol >=1514.
   CLI with netperf: netperf -H 10.66.9.242 -t TCP_STREAM -- -m 4096

Comment 2 Ronen Hod 2012-07-25 09:27:32 UTC

Closing.
We decided to freeze the XP drivers at their current phase as much as we can, so this non-critical bug is here in case we will decide to fix XP bugs.

Thanks, Ronen.

Comment 3 Yvugenfi@redhat.com 2012-07-29 11:03:48 UTC

Closing according to comment #2.