Fedora 17 warning: kernel panic after upgrade (part 2)

I have already warned about broken kernel after upgrade to Fedora 17. The issue is worse than we expected. We thought it would hit only users using development version of Fedora and it would work OK after Fedora 17 is officially released. It’s not the case, the details are in bugs 820351, 826537 and 820340. I hope the fix will be ready soon, in the meantime:

1. The current recommended order of upgrade methods is following: using Network install CD, using Install DVD, using preupgrade.
2. If  you use Network install CD, you should not encounter any kernel problems after upgrade, Fedora 17 kernel should be installed and booted by default.
3. If you use Install DVD, your kernel will not be updated to Fedora 17 version, so you will get kernel panic on every shutdown. Just run as root

   $ yum update

   to fix the issue.

4. If you use preupgrade, the new Fedora 17 kernel will be installed, but it won’t be listed in GRUB boot menu and you’ll boot the old Fedora 16 version instead. This is hardest to fix. As root you have to run

   $ grub2-install /dev/sda
   $ grub2-mkconfig -o /boot/grub2/grub.cfg

   You should replace /dev/sda with your disk you want to install bootloader on. Usually it is /dev/sda, but in some cases it might be different.

   EDIT 2012-06-04: This problem seems to be fixed now.

I hope the preupgrade issue will be fixed in the near future and the extra step won’t be necessary. DVD upgrades can’t be fixed, but in their case the problem is not that crucial as the preupgrade issue.

Fedora 17 warning: You might see a kernel panic on shutdown after upgrade

If you upgrade your Fedora 15/16 to Fedora 17 before it is officially released, there is a high probability that you encounter a bug, where your computer receives a kernel panic when you try to shut down/reboot. This is documented in bug 820351. The problem is that since Fedora 17 updates repository is still not open, your system might still have an older kernel installed. To fix this issue, just install the latest kernel from Fedora 17 updates-testing repository, like this:

$ yum update kernel\* --enablerepo=updates-testing

After one more reboot, your system should be fixed.

Please note: This bug should not appear once we officially release Fedora 17 (a.k.a GOLD), so that extra step won’t be necessary.

EDIT: The problem persists even in final release and different steps are required.

Fedora 17: Your data on USB devices are now safe(r)

There was a nasty bug in Fedora 17 related to USB devices which I blogged about recently. Rejoice, because your data is safe(r) now. GNOME developers did an outstanding job in fixing this issue. If you try to eject your USB device now, and all the data hasn’t been written to it yet, you’ll see a notification instructing you to wait. After the data operations are finished, you’ll see another notification saying that you can unplug the device now. The device will also disappear from Nautilus side pane.

There are still some less-than-optimal corner cases, e.g. you can click on that notification and hide it, but then it’s not really obvious when you can unplug the device (a second notification will pop up, just wait for it). These issues will hopefully be dealt with in a future GNOME release.

Fedora 15, 16 & 17 warning: automated system updates may break your system

Recently we have discovered a serious bug in Fedora 17, that is also present in Fedora 15 and 16 (I’m not sure about earlier releases). If you have your system updates applied automatically (which is enabled by default), you might break your system when shutting down/rebooting the computer. There is no safeguard that would tell you “please don’t turn off your computer now, system is just being updated”. No, we simply abort the update process in the middle. Horrible things may happen. Fortunately that doesn’t occur too often, but the possibility is there.

I can heartily recommend everyone to disable automatic updates until we have a proper fix ready. In GNOME just open a tool called Software settings and switch Automatically install to Nothing.

KDE guys can be happier, because they have disabled it by default. But again, I recommend to check the setting. You can find it in System settings -> Software management.

It is highly unlikely that a proper fix will land in Fedora 17 Final. We will probably just flip the option in GNOME to have nothing installed automatically by default. That is not a fix, just a way to minimize damage. A proper solution might be available no sooner than in Fedora 18. Until that time… I don’t recommend to enable this option.

Fedora 17 warning: USB devices are not unmounted correctly

 There is currently a nasty bug in Fedora 17 related to USB devices. If you copy some data to your USB flash drive/harddisk and try to eject it (either in Nautilus or using Gnome Shell tray icon), there is no indicator of progress saying whether you need to wait until all the data are written or whether you can already remove the drive. Instead you’ll get the notion that you can remove the drive immediately. But if you do this, your data might be corrupted (in case some of them haven’t been transferred yet).

There are two possible workarounds for this:

1. (easier) After you eject the device using Nautilus or Gnome Shell dialog, run a terminal and write sync. Wait until that finishes and only after that unplug the device from the computer.

2. (harder) Don’t use Nautilus or Gnome Shell to eject the device, but use umount in terminal instead. You have to be root to do this. The mount point is in /run/media/.

As you can see, none of these approaches is suitable for inexperienced users. I’ll try to make sure we won’t release Fedora 17 Final with this bug included. Until that time, please be aware of this so that you don’t lose your data.

EDIT: Follow-up post: Fedora 17: Your data on USB devices are now safe(r)