Bug 607533

Summary: Vhost:Fail to transfer file between two guests in same vlan
Product: Red Hat Enterprise Linux 4 Reporter: Michael S. Tsirkin <mst>
Component: kernelAssignee: Michael S. Tsirkin <mst>
Status: CLOSED ERRATA QA Contact: Virtualization Bugs <virt-bugs>
Severity: high Docs Contact:
Priority: medium    
Version: 4.8CC: akong, coughlan, mjenner, mst
Target Milestone: rc   
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: 607177 Environment:
Last Closed: 2011-02-16 16:02:20 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 607177    
Bug Blocks: 580954    

Comment 1 Michael S. Tsirkin 2010-06-24 10:15:48 UTC
This is a bug in virtio-net driver.
This is fixed upstream e918085aaff34086e265f825dd469926b1aec4a4:

    virtio_net: Fix MAX_PACKET_LEN to support 802.1Q VLANs
    
    802.1Q expanded the maximum ethernet frame size by 4 bytes for the
    VLAN tag.  We're not taking this into account in virtio_net, which
    means the buffers we provide to the backend in the virtqueue RX ring
    aren't big enough to hold a full MTU VLAN packet.  For QEMU/KVM,
    this results in the backend exiting with a packet truncation error.
    
    Signed-off-by: Alex Williamson <alex.williamson>
    Acked-by: Mark McLoughlin <markmc>
    Signed-off-by: David S. Miller <davem>

Comment 3 Amos Kong 2010-06-24 11:43:32 UTC
Change the guest mtu to 1490 before testing, file transferred successfully.

I'll tested with this guest kernel.
https://brewweb.devel.redhat.com/taskinfo?taskID=2549179

Comment 4 Amos Kong 2010-06-24 12:07:24 UTC
(In reply to comment #3)
> Change the guest mtu to 1490 before testing, file transferred successfully.
> 
> I'll tested with this guest kernel.
> https://brewweb.devel.redhat.com/taskinfo?taskID=2549179    

After updated guest kernel, bug could not be reproduced.

Comment 7 RHEL Program Management 2010-08-19 17:28:49 UTC
This request was evaluated by Red Hat Product Management for inclusion in a Red
Hat Enterprise Linux maintenance release.  Product Management has requested
further review of this request by Red Hat Engineering, for potential
inclusion in a Red Hat Enterprise Linux Update release for currently deployed
products.  This request is not yet committed for inclusion in an Update
release.

Comment 8 Vivek Goyal 2010-09-23 13:03:19 UTC
Committed in 89.37.EL . RPMS are available at http://people.redhat.com/vgoyal/rhel4/

Comment 11 Mike Gahagan 2011-01-06 18:49:12 UTC
confirmed with the test case in comment #0. Host used was 6.0 (64-bit) both 4.9 guests were 32 bit.

Comment 13 errata-xmlrpc 2011-02-16 16:02:20 UTC
An advisory has been issued which should help the problem
described in this bug report. This report is therefore being
closed with a resolution of ERRATA. For more information
on therefore solution and/or where to find the updated files,
please follow the link below. You may reopen this bug report
if the solution does not work for you.

http://rhn.redhat.com/errata/RHSA-2011-0263.html