Bug 629773

Summary: HVM guest w/ UP and PV driver hangs after live migration or suspend/resume
Product: Red Hat Enterprise Linux 5 Reporter: Bill Braswell <bbraswel>
Component: kernel-xenAssignee: Miroslav Rezanina <mrezanin>
Status: CLOSED ERRATA QA Contact: Virtualization Bugs <virt-bugs>
Severity: medium Docs Contact:
Priority: urgent    
Version: 5.5CC: dhoward, drjones, jpirko, jwest, mjenner, mrezanin, plyons, tao, xen-maint, yuzhang
Target Milestone: rcKeywords: ZStream
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Previously, migrating a hardware virtual machine (HVM) guest with both, UP and PV drivers, may have caused the guest to stop responding. With this update, HVM guest migration works as expected.
 Story Points: ---
Clone Of: Environment:
Last Closed: 2011-01-13 21:15:18 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:    
Bug Blocks: 630987, 630989    
Attachments:
Description Flags
Patch fixing save/restore with xen vnif device none

Description Bill Braswell 2010-09-02 22:29:21 UTC 
Description of problem:
The live migration of HVM guest w/ UP + PV driver causes its guest to hang approximately 50% of the time.  The customer does not  experience this problem w/o UP and w/o PV driver.  Live migration is similar to resume/restore.  If the customer does a restore on same machine, it causes domain to hang  100% of the time.

The dump trace is follows.
crash> bt -a
PID: 2595   TASK: ffff81001362f0c0  CPU: 0   COMMAND: 
"suspend"
#0 [ffff8100115abca0] schedule at ffffffff80063f96
#1 [ffff8100115abca8] thread_return at ffffffff80063ff8
#2 [ffff8100115abd78] read_reply at ffffffff880fc1fa
#3 [ffff8100115abe68] _spin_unlock_irqrestore at ffffffff80065b50
#4 [ffff8100115abe98] __xen_suspend at ffffffff880fb96a
#5 [ffff8100115abed8] xen_suspend at ffffffff880fb605
#6 [ffff8100115abee8] kthread at ffffffff80032bdc
#7 [ffff8100115abf48] kernel_thread at ffffffff8005efb1

Version-Release number of selected component (if applicable):
Red Hat Enterprise Linux Version Number:5.5
Release Number:
Architecture:x86, IA64
Kernel Version:2.6.18-194.el5xen
Related Package Version:none
Related Middleware / Application:none

How reproducible:
create HVM w/ UP w/ PV driver
do suspend/resume.
  
Actual results:
HVM guest hungs

Expected results:
Guest does not hang

Additional info:
I am seeing if we can get the dump
Comment 4 Miroslav Rezanina 2010-09-03 06:12:18 UTC 
This is UP variant of BZ #555910.
Comment 5 Andrew Jones 2010-09-05 14:05:57 UTC 
As Miroslav says, this is the UP variant of bug 555910, but we can take a fresh look at both cases, starting with the UP case this time. I've tried a couple experimental patches, but haven't had any luck keeping xenbus from jumping in on the suspend. Unfortunately upstream code is quite a bit different in this area, but we should still attempt this with an upstream 2.6.18-based kernel running on the full virt guest to see what happens.
Comment 8 Miroslav Rezanina 2010-09-07 09:10:56 UTC 
Created attachment 443458 [details]
Patch fixing save/restore with xen vnif device

This is a backport of c/s 15691 fixing this problem.
Comment 9 Miroslav Rezanina 2010-09-07 11:11:45 UTC 
*** Bug 573926 has been marked as a duplicate of this bug. ***
Comment 13 Miroslav Rezanina 2010-09-15 10:23:46 UTC 
Test packages containing fix can be downloaded from people.redhat.com/mrezanin/bz629773.
Comment 16 Jarod Wilson 2010-09-17 14:03:19 UTC 
in kernel-2.6.18-222.el5
You can download this test kernel from http://people.redhat.com/jwilson/el5

Detailed testing feedback is always welcomed.
Comment 19 Jaromir Hradilek 2010-10-12 22:42:27 UTC 
    Technical note added. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    New Contents:
Previously, migrating a hardware virtual machine (HVM) guest with both UP and PV drivers may have caused the guest to stop responding. With this update, HVM guest migration works as expected.
Comment 20 Martin Prpič 2010-11-11 13:56:55 UTC 
    Technical note updated. If any revisions are required, please edit the "Technical Notes" field
    accordingly. All revisions will be proofread by the Engineering Content Services team.
    
    Diffed Contents:
@@ -1 +1 @@
-Previously, migrating a hardware virtual machine (HVM) guest with both UP and PV drivers may have caused the guest to stop responding. With this update, HVM guest migration works as expected.+Previously, migrating a hardware virtual machine (HVM) guest with both, UP and PV drivers, may have caused the guest to stop responding. With this update, HVM guest migration works as expected.
Comment 21 Yufang Zhang 2010-11-18 05:40:59 UTC 
QA verified this bug with kernel-xen-2.6.18-232.el5:

1. Start a RHEL-5.4 HVM guest with vcpus=1 and memory=1024, also using netfront as the network device type.

2. save and restore the guest

For kernel-xen package(kernel-xen-2.6.18-194.8.1.el5.x86_64.rpm) without the patch, the guest would hang there after migration. But for kernel-xen-2.6.18-232.el5, the guest runs well after restore.


So change this bug to VERIFIED.
Comment 23 errata-xmlrpc 2011-01-13 21:15:18 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-2011-0017.html