udevadm trigger will fail when trying to add /sys/devices/vio/

[Thadeu Lima de Souza Cascardo]

[Impact]
This will cause the installer to exit early, causing a kernel panic before any prompt to the user. This is restricted to some Power systems.

[Test case]
A build vmlinux was used to boot the installer, and a prompt was available.
'add' was written to /sys/devices/vio/uevent was written to, and no error was found.
'add' was written to /sys/devices/vio/*/uevent, and modalias information was found when 'udevadm monitor -p' was run in the background.

A complete install was completed with a fixed kernel.

[Regression potential]
Events may be missing and coldplug/hotplug of vio devices may fail. That was tested in the test case and not found to be the case.

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1845572

[Paride Legovini (paride)]

I added a reference to this bug to the ISO tracker, however I currently can't reproduce it. Booting the installer ISO on a POWER8 machine with:

  qemu-img create -f raw disk2.img 8G
  kvm -m 1024 -boot d -cdrom eoan-server-ppc64el.iso -drive file=disk.img,if=virtio

or with:

  kvm -m 1024 -boot d -cdrom eoan-server-ppc64el.iso -drive file=disk.img

just works. The boot with if=virtio briefly shows this kernel message before the d-i actually starts:

  vio vio: uevent: failed to send synthetic uevent

but after a short while I get to the installer, and I'm able to install. This is tested with:

  $ bsdtar -x -f eoan-server-ppc64el.iso -O .disk/info
  Ubuntu-Server 19.10 "Eoan Ermine" - Beta ppc64el (20190926)

but 20190926.1 does not seem to behave differently. I'm very willing to expand the tests cases to catch this issue, however I first need to be able to reproduce it. Do you already have a reproducer?

[Thadeu Lima de Souza Cascardo (cascardo)]

This has been reproduced with http://ports.ubuntu.com/ubuntu-ports/dists/eoan-proposed/main/installer-ppc64el/current/images/netboot/mini.iso. Also with vmlinux and initrd.gz from http://ports.ubuntu.com/ubuntu-ports/dists/eoan-proposed/main/installer-ppc64el/current/images/cdrom/.

Where should I get the same image as yours?

Thanks.
Cascardo.

[Paride Legovini (paride)]

Here:

http://cdimage.ubuntu.com/ubuntu-server/daily/20190926/

$ md5sum eoan-server-ppc64el.iso
c35ce11dae512a6e4c480bc783c3a035 eoan-server-ppc64el.iso

Let me try the mini image and report back.

[Paride Legovini (paride)]

I could immediately reproduce with the mini image. The Disco mini image [0] works fine.

[0] http://ports.ubuntu.com/ubuntu-ports/dists/disco/main/installer-ppc64el/current/images/netboot/mini.iso

[Launchpad Janitor (janitor)]

This bug was fixed in the package linux - 5.3.0-17.18

---------------
linux (5.3.0-17.18) eoan; urgency=medium

  * eoan/linux: 5.3.0-17.18 -proposed tracker (LP: #1846641)

  * CVE-2019-17056
    - nfc: enforce CAP_NET_RAW for raw sockets

  * CVE-2019-17055
    - mISDN: enforce CAP_NET_RAW for raw sockets

  * CVE-2019-17054
    - appletalk: enforce CAP_NET_RAW for raw sockets

  * CVE-2019-17053
    - ieee802154: enforce CAP_NET_RAW for raw sockets

  * CVE-2019-17052
    - ax25: enforce CAP_NET_RAW for raw sockets

  * CVE-2019-15098
    - ath6kl: fix a NULL-ptr-deref bug in ath6kl_usb_alloc_urb_from_pipe()

  * xHCI on AMD Stoney Ridge cannot detect USB 2.0 or 1.1 devices.
    (LP: #1846470)
    - x86/PCI: Avoid AMD FCH XHCI USB PME# from D0 defect

  * Re-enable linux-libc-dev build on i386 (LP: #1846508)
    - [Packaging] Build only linux-libc-dev for i386
    - [Debian] final-checks -- ignore archtictures with no binaries

  * arm64: loop on boot after installing linux-generic-hwe-18.04-edge/bionic-
    proposed (LP: #1845820)
    - [Config] Disable CONFIG_ARM_SMMU_DISABLE_BYPASS_BY_DEFAULT

  * Revert ESE DASD discard support (LP: #1846219)
    - SAUCE: Revert "s390/dasd: Add discard support for ESE volumes"

  * Miscellaneous Ubuntu changes
    - update dkms package versions

linux (5.3.0-16.17) eoan; urgency=medium

  * eoan/linux: 5.3.0-16.17 -proposed tracker (LP: #1846204)

  * zfs fails to build on s390x with debug symbols enabled (LP: #1846143)
    - SAUCE: s390: Mark atomic const ops always inline

linux (5.3.0-15.16) eoan; urgency=medium

  * eoan/linux: 5.3.0-15.16 -proposed tracker (LP: #1845987)

  * Drop i386 build for 19.10 (LP: #1845714)
    - [Packaging] Remove x32 arch references from control files
    - [Debian] final-checks -- Get arch list from debian/control

  * ZFS kernel modules lack debug symbols (LP: #1840704)
    - [Debian] Fix conditional for setting zfs debug package path

  * Use pyhon3-sphinx instead of python-sphinx for building html docs
    (LP: #1845808)
    - [Packaging] Update sphinx build dependencies to python3 packages

  * Kernel panic with 19.10 beta image (LP: #1845454)
    - efi/tpm: Don't access event->count when it isn't mapped.
    - efi/tpm: don't traverse an event log with no events
    - efi/tpm: only set efi_tpm_final_log_size after successful event log parsing

linux (5.3.0-14.15) eoan; urgency=medium

  * eoan/linux: 5.3.0-14.15 -proposed tracker (LP: #1845728)

  * Drop i386 build for 19.10 (LP: #1845714)
    - [Debian] Remove support for producing i386 kernels
    - [Debian] Don't use CROSS_COMPILE for i386 configs

  * udevadm trigger will fail when trying to add /sys/devices/vio/
    (LP: #1845572)
    - SAUCE: powerpc/vio: drop bus_type from parent device

  * Trying to online dasd drive results in invalid input/output from the kernel
    on z/VM (LP: #1845323)
    - SAUCE: s390/dasd: Fix error handling during online processing

  * intel-lpss driver conflicts with write-combining MTRR region (LP: #1845584)
    - SAUCE: mfd: intel-lpss: add quirk for Dell XPS 13 7390 2-in-1

  * Support Hi1620 zip hw accelerator (LP: #1845355)
    - [Config] Enable HiSilicon QM/ZIP as module...

[Ubuntu SRU Bot (ubuntu-sru-bot)]

All autopkgtests for the newly accepted linux-gcp-5.3 (5.3.0-1008.9~18.04.1) for bionic have finished running.
The following regressions have been reported in tests triggered by the package:

linux-gcp-5.3/unknown (amd64)

Please visit the excuses page listed below and investigate the failures, proceeding afterwards as per the StableReleaseUpdates policy regarding autopkgtest regressions [1].

https://people.canonical.com/~ubuntu-archive/proposed-migration/bionic/update_excuses.html#linux-gcp-5.3

[1] https://wiki.ubuntu.com/StableReleaseUpdates#Autopkgtest_Regressions

Thank you!