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After I updated my kernel I restarted my computer (as it always requests) and now I can't log in (I can't get past the login screen). The resolution of the screen at login has also changed, leaving me to believe that the video driver I normally used was changed.

As I boot up the computer the screen at one point is momentarily black and displays the following messages:

[ 7.635692] nvidia: version magic '4.4.0-113-generic SMP mod_unload modversions 686 ' should be '4.4.0-113-generic SMP mod_unload modversions 686 retpoline '

[ 7.788685] nvidia: version magic '4.4.0-113-generic SMP mod_unload modversions 686 ' should be '4.4.0-113-generic SMP mod_unload modversions 686 retpoline '

Any suggestions as to what I can do to fix this issue? I am a novice when it comes to Ubuntu, so any help is greatly appreciated!

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KJFS
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1 Answers1

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I solved the problem by following this post from the bugs launchpad. In summary:

Run the following command and look for the vermagic line:

modinfo nvidia-384 -k 4.4.0-116-generic

It will probably say: vermagic: 4.4.0-116-generic SMP mod_unload modversions. Here the retpoline string is missing. You can fix this by removing and re-building the module with DKMS

sudo dkms remove nvidia-384/384.111 -k 4.4.0-116-generic
sudo dkms install nvidia-384/384.111 -k 4.4.0-116-generic

After that the modinfo command will show vermagic: 4.4.0-116-generic SMP mod_unload modversions retpoline

If you are using custom version of gcc this post is also relevant:

If you are using a Ubuntu version of gcc, then gcc probably updated when you got the newer kernel. The changes to gcc necessary to support retpoline should have been backported to most active versions of gcc. However if you have installed a custom version of gcc then your kernel module probably will not build correctly.

So if the above procedure does not work you may have to check which gcc version you are using.

bluenote10
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