From this morning the boot process on my laptop is no longer working. The only relevant change from yesterday (when all was working fine) has been a kernel update (from 3.2.0-39-generic to 3.2.0-40-generic).
When grub tries to boot the 3.2.0-40-generic kernel, I get only a black screen (the screen seems powered off).
After many tries and googling around, I found the following: if I change the CMDLINE_LINUX_DEFAULT grub parameter (inside /etc/default/grub) from the default value "quiet splash" to "nomodeset" the boot process works but the screen has a lower resolution than before (from 1600x900 to 800x600).
This is not happening with the previous kernel version (3.2.0-39-generic). Even with "quiet splash" enabled, all is working fine with the correct resolution.
An important note: my disk is fully encrypted (actually the setup is LVM + encryption). So when the boot works fine, after the grub selection screen I am asked to insert the passphrase for decrypting the whole file system.
Is there a way to fix this misbehaviour? I would like to avoid workarounds like using always an old kernel or using "nomodeset" as a default parameter.
Thank you in advance