Bug 2070066

Summary: VMs hang when trying to access virtiofs mounts in the guest VM
Product: [Fedora] Fedora Reporter: Neal Gompa <ngompa13>
Component: qemuAssignee: Fedora Virtualization Maintainers <virt-maint>
Status: CLOSED ERRATA QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: unspecified Docs Contact:
Priority: unspecified    
Version: 36CC: awilliam, bcotton, berrange, cfergeau, crobinso, fzatlouk, gmarr, ondrejj, pbonzini, philmd, prkumar, rjones, robatino, virt-maint
Target Milestone: ---   
Target Release: ---   
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: RejectedBlocker AcceptedFreezeException
Fixed In Version: qemu-6.2.0-6.fc36 Doc Type: If docs needed, set a value
Doc Text:
Story Points: ---
Clone Of: Environment:
Last Closed: 2022-04-08 02:56:52 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:
Bug Depends On:    
Bug Blocks: 1953786    

Description Neal Gompa 2022-03-30 12:03:11 UTC
Description of problem:
When trying to use virtiofs mounts between guest and host, the VM hangs and needs to be killed.

Version-Release number of selected component (if applicable):
6.2.0-5.fc36

How reproducible:
Always

Steps to Reproduce:
1. Set up a mount following the instructions here: https://libvirt.org/kbase/virtiofs.html

Actual results:
VM hangs

Expected results:
virtiofs mount succeeds and transparent access to host filesystem resources works.

Additional info:
The journal indicates that what's happening in the background is that virtiofsd on the host is crashing when the mount request is made.

Comment 1 Neal Gompa 2022-03-30 12:07:06 UTC
I have pull requests open to fix the problem:

- Rawhide: https://src.fedoraproject.org/rpms/qemu/pull-request/21
- F36: https://src.fedoraproject.org/rpms/qemu/pull-request/22

Comment 2 Neal Gompa 2022-03-30 12:42:36 UTC
I believe this qualifies as final blocker because it violates the following criteria: "The release must be able host virtual guest instances of the same release [using QEMU+KVM on libvirt]."

Being able to share files between host and guest is a critical path for things like Vagrant and is often used in developer virtualization scenarios, so we should make sure it works.

Comment 3 Adam Williamson 2022-04-01 21:45:39 UTC
Neal, could you address my comment on the pull request? I posted it on the F37 one, but it applies to the F36 one also.

Comment 4 Neal Gompa 2022-04-01 22:24:12 UTC
(In reply to Adam Williamson from comment #3)
> Neal, could you address my comment on the pull request? I posted it on the
> F37 one, but it applies to the F36 one also.

This is now done for both of them.

Comment 5 Adam Williamson 2022-04-01 22:40:27 UTC
Well, you added a link to this bug report, but not to anything upstream. There is no indication of the source of the patches. Mystery patches in spec files aren't a great idea. It's much better with a link to an upstream issue, PR, or commit log.

Comment 6 Ben Cotton 2022-04-04 13:02:38 UTC
Nominating for freeze exception, since the blocker vote is trending negative.

Comment 7 FrantiĊĦek Zatloukal 2022-04-04 14:33:48 UTC
Discussed in ticket: https://pagure.io/fedora-qa/blocker-review/issue/698

The decision to classify this bug as an RejectedBlocker was made:

"We don't have release criterion that covers this issue."

Comment 8 Geoffrey Marr 2022-04-04 15:50:40 UTC
Discussed using the asynchronous bug tracking platform: [0]

The decision to classify this bug as an "AcceptedFreezeException (Final)" was made as it is a noticeable issue that cannot be fixed with an update.

[0] https://qa.fedoraproject.org/blockerbugs/

Comment 9 Fedora Update System 2022-04-04 18:00:39 UTC
FEDORA-2022-ce985654bc has been submitted as an update to Fedora 36. https://bodhi.fedoraproject.org/updates/FEDORA-2022-ce985654bc

Comment 10 Fedora Update System 2022-04-05 12:41:11 UTC
FEDORA-2022-ce985654bc has been pushed to the Fedora 36 testing repository.
Soon you'll be able to install the update with the following command:
`sudo dnf upgrade --enablerepo=updates-testing --advisory=FEDORA-2022-ce985654bc`
You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2022-ce985654bc

See also https://fedoraproject.org/wiki/QA:Updates_Testing for more information on how to test updates.

Comment 11 Fedora Update System 2022-04-08 02:56:52 UTC
FEDORA-2022-ce985654bc has been pushed to the Fedora 36 stable repository.
If problem still persists, please make note of it in this bug report.