Hi, forum. I have elementary OS (based on 14.04.1-Ubuntu) installed on a laptop. When unplugged, system crashes, and only a black screen appears. When launching in safe mode from Grub, the same log is seen: Code: [ 1336.668635] BUG: unable to handle kernel NULL pointer dereference at 0000000000000001 IP: [<ffffffff8143e7b4>] acpi_idle_enter_bm+0x48/0x23a [ 1336.668803] PGD 78083067 PUD 78084067 PMD 0 [ 1336.668848] Oops: 0000 [#1] SMP ... (similar lines with colons here) ... [ 1336.672569] drm_kms_helper: panic occured, switching back to text console . I tried boot-repair in reinstalling Grub: nah, it seems that the issue is with the kernel (3.160-46-generic), very specific though. I tried reporting a bug on Launchpad: seems that me alone I have this problem( Does anybody know, if there's a way it can be solved? Are there any other forums, users of which can catch the thing? Please help.