kernel crashes on boot (ubuntu as a Hyper-V guest)

[Nils Schmidt]

My Ubuntu 14.04 VM (Hyper-V / Windows Server 2008 R2) crashes directly after the grub boot loader screen. Kernel packages linux-image-3.13.0-62-generic and linux-image-3.13.0-63-generic are affected while linux-image-3.13.0-61-generic works like all previous versions did. Unfortunatly no /var/log/kern.log is written at all with the affected kernels.

[Brad Figg (brad-figg)]

This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:

apport-collect 1492331

and then change the status of the bug to 'Confirmed'.

If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.

This change has been made by an automated script, maintained by the Ubuntu Kernel Team.

[Nils Schmidt (nils-p-schmidt)]

As stated in the desciption and shown in my screenshots I am not able to run apport-collect. Please feel free to request further data.

[Joseph Salisbury (jsalisbury)]

I started a kernel bisect between 3.113.0-61 and v3.13.0-62. The kernel bisect will require testing of about 7 test kernels.

I built the first test kernel, up to the following commit:
c9e258e9b4b1ffd3e83c7c3a1510965c43657ba6

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

Thank you very much for your help! Unfortunately the VM is installed as i386. I can't remember why, but maybe I hoped it whould use less RAM with this arch.

[Joseph Salisbury (jsalisbury)]

Sorry about that. I built a 32 bit kernel now.

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

Thanks again!

The Kernel you build does not work. The screen is nealy the same.

[Joseph Salisbury (jsalisbury)]

I built the next test kernel up to the following commit:
9d7f5772c60ddae92aa8078519e3ad98097d3d51

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

This one does not work too. It's nearly the same except for the recovery mode crashing exactly like the standard mode.

[Joseph Salisbury (jsalisbury)]

I built the next test kernel up to the following commit:
059657a34c9db62086f57e6b5b1be5d5adb00a3a

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

The newest one is affected aswell.

Can you exclude that the problem is toolchain related?

[Joseph Salisbury (jsalisbury)]

I don't think this is toolchain related due to the kernel crash.

I built the next test kernel up to the following commit:
97b2591fbecaa0366939bb5fdfecd79fe914de22

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

The newest one is affected aswell.

[Joseph Salisbury (jsalisbury)]

I don't think this is toolchain related due to the kernel crash.

I built the next test kernel up to the following commit:
c66bbb56d0b3e4846959a0b96be21ea837f5f9e0

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

This is the first working one.

[Joseph Salisbury (jsalisbury)]

I built the next test kernel up to the following commit:
0ed946728a5f31c7720e910579ef39317450cc07

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

This one is working fine.

[Joseph Salisbury (jsalisbury)]

I built the next test kernel up to the following commit:
426701e6cc8a34ba6a48e5e8f312d32e09b398cc

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

This one is working.

[Joseph Salisbury (jsalisbury)]

I built the next test kernel up to the following commit:
20c22866a08980b2e2065d6c61161542e53c7346

The test kernel can be downloaded from:
http://kernel.ubuntu.com/~jsalisbury/lp1492331

Can you test that kernel and report back if it has the bug or not? I will build the next test kernel based on your test results.

Thanks in advance

[Nils Schmidt (nils-p-schmidt)]

This one is working aswell.

[Joseph Salisbury (jsalisbury)]

It appears this is the first bad commit:

97b2591fbecaa0366939bb5fdfecd79fe914de22

I built a test kernel with this commit reverted. Can you test this kernel and see if it resolves this bug? It can be downloaded from:

http://kernel.ubuntu.com/~jsalisbury/lp1492331

[Nils Schmidt (nils-p-schmidt)]

Yes, that kernel works!

[Joseph Salisbury (jsalisbury)]

This bug appears to be a duplicate of bug 1495983 , which was reported to affect Wily and Vivid. Reverting the same commit also resolves that bug, so I'll mark this as a duplicate bug and add a Trusty bug task to that bug.