Bug 2118519

Summary:	veth can't be created on s390x kernel
Product:	[Fedora] Fedora	Reporter:	Jianlin Shi <jishi>
Component:	kernel	Assignee:	Kernel Maintainer List <kernel-maint>
Status:	CLOSED CURRENTRELEASE	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	medium	Docs Contact:
Priority:	unspecified
Version:	rawhide	CC:	acaringi, adscvr, airlied, alciregi, bskeggs, dvlasenk, hdegoede, hpa, jarodwilson, jglisse, jonathan, josef, kernel-maint, lgoncalv, linville, masami256, mchehab, ptalbert, scweaver, steved
Target Milestone:	---	Keywords:	TestBlocker
Target Release:	---
Hardware:	s390x
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2023-02-03 17:10:35 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 Jianlin Shi 2022-08-16 03:05:48 UTC

1. Please describe the problem:
veth can't be created on s390x kernel

2. What is the Version-Release number of the kernel:
5.20.0-0.rc0.3bc1bc0b59d0.9.test.fc37.s390x

3. Did it work previously in Fedora? If so, what kernel version did the issue
   *first* appear?  Old kernels are available for download at
   https://koji.fedoraproject.org/koji/packageinfo?packageID=8 :


4. Can you reproduce this issue? If so, please provide the steps to reproduce
   the issue below:

ip link add veth0 type veth

5. Does this problem occur with the latest Rawhide kernel? To install the
   Rawhide kernel, run ``sudo dnf install fedora-repos-rawhide`` followed by
   ``sudo dnf update --enablerepo=rawhide kernel``:


6. Are you running any modules that not shipped with directly Fedora's kernel?:


7. Please attach the kernel logs. You can get the complete kernel log
   for a boot with ``journalctl --no-hostname -k > dmesg.txt``. If the
   issue occurred on a previous boot, use the journalctl ``-b`` flag.


[root@ibm-z-521 ~]# uname -a
Linux ibm-z-521.lab.eng.rdu2.redhat.com 5.20.0-0.rc0.3bc1bc0b59d0.9.test.fc37.s390x #1 SMP Fri Aug 12 11:56:35 UTC 2022 s390x s390x s390x GNU/Linux
[root@ibm-z-521 ~]# ip link add veth0 type veth
Error: Invalid number of transmit queues.

it happened in the job: https://gitlab.com/redhat/centos-stream/tests/kernel/kernel-tests/-/issues/1346#note_1065491803

Comment 1 Denys Vlasenko 2022-12-07 14:31:32 UTC

Works on 6.0.11-300.fc37.s390x kernel.

(In fact, "ip link add veth0 type veth" command is not going to work anywhere, you need to supply peer name:
# ip link add veth0 type veth
RTNETLINK answers: File exists
).

I see this command running successfully:

# ip link add veth0 type veth peer name veth0p
# ip l
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: enc8000: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP mode DEFAULT group default qlen 1000
    link/ether 02:de:ad:be:ef:87 brd ff:ff:ff:ff:ff:ff
4: veth0p@veth0: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether de:21:7c:c5:36:2a brd ff:ff:ff:ff:ff:ff
5: veth0@veth0p: <BROADCAST,MULTICAST,M-DOWN> mtu 1500 qdisc noop state DOWN mode DEFAULT group default qlen 1000
    link/ether d2:59:c8:bb:76:34 brd ff:ff:ff:ff:ff:ff

Comment 2 Denys Vlasenko 2022-12-07 14:36:18 UTC

works on 5.19.16-301.fc37.s390x as well (tested on the same machine)

Comment 3 Scott Weaver 2023-02-03 17:10:35 UTC

Hi Jianlin

I'm closing this based on the comments in [1] which is now closed.
If you see this issue again feel free to re-open this BZ.

[1] https://gitlab.com/redhat/centos-stream/tests/kernel/kernel-tests/-/issues/1346#note_1065491803