kernel-packages team mailing list archive

[Dimitri John Ledkov <launchpad@xxxxxxxxxxxx>]

For LPAR -> it's a valid test to verity max speed and actual speeds
For z/VM -> the cards are virtualised on the host, thus any test of max & actual speeds is bogus
For z/KVM -> the cards are virtualised on the host, thus any test of max & actual speeds is bogus
Comparing z/VM and z/KVM with other architectures is also bogus, as completely different kernel drivers are used to implement the cards (qeth driver on a CCW bus and CCW-virtio bus, CCW buses are entirely s390x specific)

At best this is a wishlist bug report against upstream z/VM & upstream
qemu to expose something more realistic in the guest, which kernel then
can pick up and display. What kernel is showing to you, is as much as it
knows, and there is no bug there as far as I can tell.

-- 
You received this bug notification because you are a member of Kernel
Packages, which is subscribed to linux in Ubuntu.
https://bugs.launchpad.net/bugs/1572347

Title:
  problems with network speed reporting in sysfs on s390

Status in linux package in Ubuntu:
  Confirmed

Bug description:
  On an amd64 system with a 1Gb NIC, I can examine
  /sys/class/net/<DEVICE> for various bits of data.  In this case, we
  need link speed.

  For example:

  bladernr@galactica:~/Datacenters/Home$ cat /sys/class/net/enp2s0/speed 
  1000

  However, on my z/VM instance of Xenial on s390, the reported speed is WAY below what it actually is:
  hwe@hwe-zvm1:/sys/class/net/enc600$ cat speed
  10

  iperf confirms that this virtual device is actually functioning at 1Gb
  speeds.  This is causing failures in the cert networking tests that
  probe for reported link speed and then compare that to reported
  maximum speed.

  On a zKVM instance of Xenial, this is even worse as I am completely
  unable to examine /sys/class/net/<DEVICE>/speed at all:

  hwe@s1lp9g003:~$ cat /sys/class/net/eth0/speed 
  cat: /sys/class/net/eth0/speed: Invalid argument
  hwe@s1lp9g003:/sys/class/net/eth0$ ll
  total 0
  drwxr-xr-x 5 root root    0 Apr 19 20:02 ./
  drwxr-xr-x 3 root root    0 Apr 19 20:02 ../
  -r--r--r-- 1 root root 4096 Apr 19 20:02 addr_assign_type
  -r--r--r-- 1 root root 4096 Apr 19 20:02 addr_len
  -r--r--r-- 1 root root 4096 Apr 19 20:02 address
  -r--r--r-- 1 root root 4096 Apr 19 20:02 broadcast
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 carrier
  -r--r--r-- 1 root root 4096 Apr 19 20:02 carrier_changes
  -r--r--r-- 1 root root 4096 Apr 19 20:02 dev_id
  -r--r--r-- 1 root root 4096 Apr 19 20:02 dev_port
  lrwxrwxrwx 1 root root    0 Apr 19 20:02 device -> ../../../virtio1/
  -r--r--r-- 1 root root 4096 Apr 19 20:02 dormant
  -r--r--r-- 1 root root 4096 Apr 19 20:02 duplex
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 flags
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 gro_flush_timeout
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 ifalias
  -r--r--r-- 1 root root 4096 Apr 19 20:02 ifindex
  -r--r--r-- 1 root root 4096 Apr 19 20:02 iflink
  -r--r--r-- 1 root root 4096 Apr 19 20:02 link_mode
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 mtu
  -r--r--r-- 1 root root 4096 Apr 19 20:02 name_assign_type
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 netdev_group
  -r--r--r-- 1 root root 4096 Apr 19 20:02 operstate
  -r--r--r-- 1 root root 4096 Apr 19 20:02 phys_port_id
  -r--r--r-- 1 root root 4096 Apr 19 20:02 phys_port_name
  -r--r--r-- 1 root root 4096 Apr 19 20:02 phys_switch_id
  drwxr-xr-x 2 root root    0 Apr 19 20:02 power/
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 proto_down
  drwxr-xr-x 4 root root    0 Apr 19 20:02 queues/
  -r--r--r-- 1 root root 4096 Apr 19 20:02 speed
  drwxr-xr-x 2 root root    0 Apr 19 20:02 statistics/
  lrwxrwxrwx 1 root root    0 Apr 19 20:02 subsystem -> ../../../../../../../class/net/
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 tx_queue_len
  -r--r--r-- 1 root root 4096 Apr 19 20:02 type
  -rw-r--r-- 1 root root 4096 Apr 19 20:02 uevent
  hwe@s1lp9g003:/sys/class/net/eth0$ sudo cat speed
  cat: speed: Invalid argument
  hwe@s1lp9g003:/sys/class/net/eth0$ sudo su
  root@s1lp9g003:/sys/devices/css0/0.0.0001/0.0.0001/virtio1/net/eth0# cat speed
  cat: speed: Invalid argument

  So on zKVM even root is not able to view the current link speed.

  ProblemType: Bug
  DistroRelease: Ubuntu 16.04
  Package: linux-image-4.4.0-18-generic 4.4.0-18.34
  ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
  Uname: Linux 4.4.0-18-generic s390x
  AlsaDevices: Error: command ['ls', '-l', '/dev/snd/'] failed with exit code 2: ls: cannot access '/dev/snd/': No such file or directory
  AplayDevices: Error: [Errno 2] No such file or directory: 'aplay'
  ApportVersion: 2.20.1-0ubuntu2
  Architecture: s390x
  ArecordDevices: Error: [Errno 2] No such file or directory: 'arecord'
  CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found.
  Date: Tue Apr 19 22:58:52 2016
  HibernationDevice: RESUME=UUID=7ddabd20-1d15-492c-bcd5-ec2dbb16b777
  IwConfig: Error: [Errno 2] No such file or directory: 'iwconfig'
  Lspci:
   
  Lsusb: Error: command ['lsusb'] failed with exit code 1:
  PciMultimedia:
   
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=en_US.UTF-8
   SHELL=/bin/bash
  ProcFB: Error: [Errno 2] No such file or directory: '/proc/fb'
  ProcKernelCmdLine: root=UUID=b732515f-dacf-4007-85af-a27b5bf48fdf crashkernel=196M BOOT_IMAGE=0
  RelatedPackageVersions:
   linux-restricted-modules-4.4.0-18-generic N/A
   linux-backports-modules-4.4.0-18-generic  N/A
   linux-firmware                            1.157
  RfKill: Error: [Errno 2] No such file or directory: 'rfkill'
  SourcePackage: linux
  UpgradeStatus: No upgrade log present (probably fresh install)
  --- 
  AlsaDevices: Error: command ['ls', '-l', '/dev/snd/'] failed with exit code 2: ls: cannot access '/dev/snd/': No such file or directory
  AplayDevices: Error: [Errno 2] No such file or directory
  ApportVersion: 2.20.1-0ubuntu2
  Architecture: s390x
  ArecordDevices: Error: [Errno 2] No such file or directory
  CRDA: Error: command ['iw', 'reg', 'get'] failed with exit code 1: nl80211 not found.
  DistroRelease: Ubuntu 16.04
  HibernationDevice: RESUME=UUID=7ddabd20-1d15-492c-bcd5-ec2dbb16b777
  IwConfig: Error: [Errno 2] No such file or directory
  Lspci:
   
  Lsusb: Error: command ['lsusb'] failed with exit code 1:
  Package: linux (not installed)
  PciMultimedia:
   
  ProcEnviron:
   TERM=xterm
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=en_US.UTF-8
   SHELL=/bin/bash
  ProcFB: Error: [Errno 2] No such file or directory: '/proc/fb'
  ProcKernelCmdLine: root=UUID=b732515f-dacf-4007-85af-a27b5bf48fdf crashkernel=196M BOOT_IMAGE=0
  ProcVersionSignature: Ubuntu 4.4.0-18.34-generic 4.4.6
  RelatedPackageVersions:
   linux-restricted-modules-4.4.0-18-generic N/A
   linux-backports-modules-4.4.0-18-generic  N/A
   linux-firmware                            1.157
  RfKill: Error: [Errno 2] No such file or directory
  Tags:  xenial
  Uname: Linux 4.4.0-18-generic s390x
  UpgradeStatus: No upgrade log present (probably fresh install)
  UserGroups: adm cdrom cpacfstats dip lpadmin lxd plugdev sambashare sudo
  _MarkForUpload: True

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1572347/+subscriptions