Bug 808114

Summary:	streaming with no backing file should not do anything
Product:	Red Hat Enterprise Linux 6	Reporter:	Paolo Bonzini <pbonzini>
Component:	qemu-kvm	Assignee:	Paolo Bonzini <pbonzini>
Status:	CLOSED DEFERRED	QA Contact:	Virtualization Bugs <virt-bugs>
Severity:	unspecified	Docs Contact:
Priority:	unspecified
Version:	6.3	CC:	acathrow, areis, bsarathy, dyasny, juzhang, mkenneth, pbonzini, shu, virt-maint
Target Milestone:	rc
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:		Story Points:	---
Clone Of:
Clones:	965636 (view as bug list)		Environment:
Last Closed:	2013-05-21 13:00:42 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:	806280, 965636

Description Paolo Bonzini 2012-03-29 15:47:31 UTC

Description of problem:
Streaming an image with no backing file wastes time copying the whole image onto itself.

Version-Release number of selected component (if applicable):
qemu-kvm 267rhev

How reproducible:
100%

Steps to Reproduce:
1. install to qcow2
2. start QEMU
3. do block_stream virtio0
  
Actual results:
Streaming job runs

Expected results:
Streaming job ends immediately

Additional info:
Also related, streaming should not even start if the image format does not support bdrv_change_backing_file.

Comment 1 juzhang 2012-03-31 03:05:27 UTC

Can reproduce with qemu-kvm-267.el6ev.

1.boot guest with qcow2
2.block_stream virtio0
3.info block-jobs

Resutls
(qemu) info block-jobs 
Streaming device virtio0: Completed 12817137664 of 21474836480 bytes, speed limit 0 bytes/s

Comment 4 Paolo Bonzini 2013-05-21 13:00:42 UTC

Deferred to 7.0 (bug 965636).