Comment 0 for bug 1776005

Hello,

As explained yesterday on #ubuntu-kernel, several laptop won't boot (kernel panic) with the latest kernel 4.4.0-127-generic (x86_64) and upper (proposed 4.4.0-128-generic), on Xenial 16.04 LTS

I have made many tests to verify that the bootloader (GRUB) is correctly configured (I have also reinstall it, but same result).

I have also verified the BTRFS system is clean and not corrupted (with a livecd).

The behavior is unpredictable, because often the kernel fall in "panic" during boot, but not all the time, if i do several consecutive reboot to test stability of the boot "process". I have no search behavior with previous kernels (like 4.4.0-127-generic).

I suspect (even if I'm quiet disturbed by this behavior, maybe I wrong) that something I changed on last kernel:
- on BTRFS subsystem, I have "aggregate" BTRFS partitions as rootfs (for a long time)
- something related with the last mitigation about the recent security processor breach

But my skills stop here, and I'm not able to find the origin of this behavior despite my efforts.
I can continue my investigation if I have some additional pointers.

Thanks for your time,

Sylvain