Bug#797131: udev kernel check during Wheezy->Jessie upgrade should happen earlier

[Andy Valencia]

Package: udev
Version: 175-7.2
Severity: serious
Justification: Policy 7.2

Dear Maintainer,

   * What led up to the situation?

Upgrading my armhf system Wheezy->Jessie.  Did the usual searches for
dependencies and what-not.  Did a pre-download, then ran the upgrade.
About half the packages were churned, and then udev declares:

    Since release 198, udev requires support for the following features in
    the running kernel:

    - inotify(2)            (CONFIG_INOTIFY_USER)
    - signalfd(2)           (CONFIG_SIGNALFD)
    - accept4(2)
    - open_by_handle_at(2)  (CONFIG_FHANDLE)
    - timerfd_create(2)     (CONFIG_TIMERFD)
    - epoll_create(2)       (CONFIG_EPOLL)

    Please upgrade your kernel before or while upgrading udev.

and the upgrade fails.  I'd be happy to reconfigure my kernel, but with
half my files upgraded and the other half not, my system was not well
enough to do anything.

   * What exactly did you do (or not do) that was effective (or
     ineffective)?

I'm not an idiot; I had a full backup and restored my system.

   * What was the outcome of this action?

Failed upgrade.  New required kernel features (it'd be nice if that
was listed somewhere).

   * What outcome did you expect instead?

If the kernel is not acceptable for the upgrade, it should be detected
before the upgrade starts.  The kernel check should not happen after the
filesystem has been modified with some upgraded content.  An upgrade
should never start if it can be determined that it can't complete
successfully.



-- System Information:
Debian Release: 7.8
  APT prefers oldstable
  APT policy: (500, 'oldstable')
Architecture: armhf (armv7l)

Kernel: Linux 3.4.75+ (SMP w/2 CPU cores; PREEMPT)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=ANSI_X3.4-1968) (ignored: LC_ALL set to C)
Shell: /bin/sh linked to /bin/dash

Versions of packages udev depends on:
ii  debconf [debconf-2.0]  1.5.49
ii  libc6                  2.13-38+deb7u8
ii  libgcc1                1:4.7.2-5
ii  libselinux1            2.1.9-5
ii  libudev0               175-7.2
ii  lsb-base               4.1+Debian8+deb7u1
ii  procps                 1:3.3.3-3
ii  util-linux             2.20.1-5.3

Versions of packages udev recommends:
ii  pciutils  1:3.1.9-6
ii  usbutils  1:005-3

udev suggests no packages.

-- debconf information:
  udev/new_kernel_needed: false
  udev/title/upgrade:
  udev/reboot_needed:
  udev/sysfs_deprecated_incompatibility: