[Bug 1560545] Re: Some or all OSA devices may be unavailable after boot if too many are visible

[Dimitri John Ledkov]

hwup is racy, when compared with chzdev udev-rules.
specifically since the wait_for_sysfs key has been removed from udev, the current hwup doesn't wait for the complete group to be available before attempting to activate it. And it doesn't attempt to do so again.

I would like to do following
1) change installer to generate chzdev based configs only
2) upgrade existing users of hwup configs to chzdev configs, on best effort basis
3) drop sysconfig-hardware package (install time runtime) from the archive and default installations

** Also affects: s390-sysconfig-writer (Ubuntu)
   Importance: Undecided
       Status: New

** Also affects: s390-tools (Ubuntu)
   Importance: Undecided
       Status: New

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Title:
  Some or all OSA devices may be unavailable after boot if too many are
  visible

Status in s390-sysconfig-writer package in Ubuntu:
  New
Status in s390-tools package in Ubuntu:
  New
Status in sysconfig package in Ubuntu:
  New
Status in systemd package in Ubuntu:
  New

Bug description:
  -- Problem Description --
  Ubuntu 16.04 kernel 4.4.0-13 is installed on LPAR without cio_ignore in kernel command line, so a lot of devices are visible:

  root at s83lp41:~# ls -1U /sys/bus/ccw/drivers/qeth | wc -l
  154
  (50 OSA triplets + 4 non-devices)

  With so many devices the system may boot (initial or reboot) with only
  some or no interfaces brought up. A network is configured only on some
  of the triplets; the issue is well reproduced with two interfaces.

  lsqeth shows only active interfaces
  Inactive cannot be brought up with ifup:

  root at s83lp41:~# ifup encb080
  Cannot find device "encb080"
  Failed to bring up encb080.

  However, they become available after manually issuing hwup:

  root at s83lp41:~# hwup -A -D /devices/css0/0.0.1c67/0.0.b080 ccw 0.0.b080
  Configuring device 0.0.b080: ok. (portname OSAPORT) (portno 0) ok.

  After hwup interfaces are configured automatically and are listed in
  lsqeth.

  root at s83lp41:~# ifup encb080
  ifup: waiting for lock on /run/network/ifstate.encb080
  ifup: interface encb080 already configured

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