Note: This bug is displayed in read-only format because the product is no longer active in Red Hat Bugzilla.
RHEL Engineering is moving the tracking of its product development work on RHEL 6 through RHEL 9 to Red Hat Jira (issues.redhat.com). If you're a Red Hat customer, please continue to file support cases via the Red Hat customer portal. If you're not, please head to the "RHEL project" in Red Hat Jira and file new tickets here. Individual Bugzilla bugs in the statuses "NEW", "ASSIGNED", and "POST" are being migrated throughout September 2023. Bugs of Red Hat partners with an assigned Engineering Partner Manager (EPM) are migrated in late September as per pre-agreed dates. Bugs against components "kernel", "kernel-rt", and "kpatch" are only migrated if still in "NEW" or "ASSIGNED". If you cannot log in to RH Jira, please consult article #7032570. That failing, please send an e-mail to the RH Jira admins at rh-issues@redhat.com to troubleshoot your issue as a user management inquiry. The email creates a ServiceNow ticket with Red Hat. Individual Bugzilla bugs that are migrated will be moved to status "CLOSED", resolution "MIGRATED", and set with "MigratedToJIRA" in "Keywords". The link to the successor Jira issue will be found under "Links", have a little "two-footprint" icon next to it, and direct you to the "RHEL project" in Red Hat Jira (issue links are of type "https://issues.redhat.com/browse/RHEL-XXXX", where "X" is a digit). This same link will be available in a blue banner at the top of the page informing you that that bug has been migrated.

Bug 1294419

Summary: qemu promt "processing error - resetting ehci HC " after send "ctrl-alt-delete" to guest
Product: Red Hat Enterprise Linux 6 Reporter: Qianqian Zhu <qizhu>
Component: qemu-kvmAssignee: Gerd Hoffmann <kraxel>
Status: CLOSED NEXTRELEASE QA Contact: Virtualization Bugs <virt-bugs>
Severity: low Docs Contact:
Priority: low    
Version: 6.8CC: ailan, mkenneth, qizhu, rbalakri, virt-maint
Target Milestone: rc   
Target Release: ---   
Hardware: x86_64   
OS: Linux   
Whiteboard:
Fixed In Version: Doc Type: Bug Fix
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2016-01-15 11:37:19 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 Qianqian Zhu 2015-12-28 07:13:23 UTC 
Description of problem:
boot a guest with usb device, boot failed from usb device, then send "ctrl-alt-delete" to guest via remote-viewer, qemu promt "Request for more bytes than allowed, processing error - resetting ehci HC "

Version-Release number of selected component (if applicable):
kernel-2.6.32-590.el6.x86_64
qemu-kvm-rhev-0.12.1.2-2.482.el6.x86_64

How reproducible:
100%

Steps to Reproduce:
1.launch guest with: 
/usr/libexec/qemu-kvm -name virtio -m 1024 -cpu Westmere,check -realtime mlock=off -smp 2 -global PIIX4_PM.disable_s4=1 -boot order=c,menu=on -device virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x6 -drive file=/home/sn1_rhel6.7_virtio.qcow2,format=qcow2,if=none,id=block-virtio,cache=none,werror=stop,rerror=stop -device virtio-blk-pci,bus=pci.0,addr=0x8,drive=block-virtio,id=block-virtio -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x7 -monitor stdio -vnc :4 -vga cirrus -device usb-ehci,id=ehci -drive file=/home/usb.qcow2,if=none,id=drive-usb-2-0,media=disk,format=raw,cache=none -device usb-storage,drive=drive-usb-2-0,id=usb-0-0,removable=on,bus=ehci.0,port=1 -device e1000,netdev=hostnet0,id=net0,mac=D4:AE:52:E9:57:36 -netdev tap,id=hostnet0,vhost=on

2.send "ctrl-alt-delete" after boot failed.
3.

Actual results:
(qemu) Request for more bytes than allowed
processing error - resetting ehci HC

Expected results:
no error prompt

Additional info:
Comment 2 Gerd Hoffmann 2016-01-04 12:39:26 UTC 
It's probably ehci data structures being overwritten, therefore ehci going to read and trying to process gibberish.  Happens because we do a soft reset on ctrl-alt-del in RHEL-6.  Should be fixed in RHEL-7 because we do a hard reset there.

It should have no side effects other than printing this debug message, i.e. the guest should re-initialize ehci and should be able to continue using it.

Is that correct?
Comment 3 Qianqian Zhu 2016-01-05 01:13:47 UTC 
(In reply to Gerd Hoffmann from comment #2)
> It's probably ehci data structures being overwritten, therefore ehci going
> to read and trying to process gibberish.  Happens because we do a soft reset
> on ctrl-alt-del in RHEL-6.  Should be fixed in RHEL-7 because we do a hard
> reset there.
> 
> It should have no side effects other than printing this debug message, i.e.
> the guest should re-initialize ehci and should be able to continue using it.
> 
> Is that correct?

Yes, guest was able to continue using it, it could not be noticed by user if there is no debug message.
Comment 4 Ademar Reis 2016-01-15 11:37:19 UTC 
Cornercase, harmless, fixed in rhel7/upstream already.