I am attaching a screen shot of my problem because it looks so similar and I haven't had any luck in solving it. I can still boot with the Linux 3.19.0-21-generic kernel from the Grub menu. However the more recent versions (22 through 25) are not booting. I am not sure how to tell for certain but it looks more and more like the same kind of problem.
** Attachment added: "IMG_20150807_145055965_HDR.jpg" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1475941/+attachment/4441216/+files/IMG_20150807_145055965_HDR.jpg -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1475941 Title: Kernel panic - not syncing To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1475941/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs