BBRv2 v2alpha installation issue

[Yuanlai]

Hi All,

     I followed the the recipe in the BBR v2alpha README. The installation process looks good and no error was generated. I checked 'uname -a ', it only showed my current kernel version(linux-image-5.15.0.72), and I didn't see the branch name SHA1 hash. In addition, only 'reno cubic' was shown after I checked the  'sysctl net.ipv4.tcp_available_congestion_control'

     When I checked the 'Advanced options for ubuntu', I found my current kernel version(linux-image-5.15.0.72) and also the bbrv2 v2alpha kernel(linux-image-5.13.12-v2alpha). 

     I tired to load the bbrv2 v2alpha kernel, but the screen stuck at login in state and the keyboard and mouse stopped working. So, I can't login into the bbrv2 v2alpha kernel.

    So, do you know what's my problem? thank you for your help!

Thanks,

Yuanlai