kernel-packages team mailing list archive

["Christopher M. Penalver" <christopher.m.penalver@xxxxxxxxx>]

** Tags added: needs-kernel-logs needs-upstream-testing

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https://bugs.launchpad.net/bugs/1057532

Title:
  Monitor goes black ("no signal") after Grub, comes back to life when X
  starts

Status in “linux” package in Ubuntu:
  Confirmed

Bug description:
  After selecting an entry from the Grub menu and booting starts, the screen goes blank, and the monitor displays "no signal". When booting ends and X starts up, the screen comes back to life, and the LightDM login screen appears.
  I'm using a Radeon HD 6850 with the opensource driver.

  Kernel version: 3.5.0-15.23-generic 3.5.4

  This is a regression, as the issue wasn't present with an earlier 3.5 kernel.
  When I updated recently, I updated to kernel version 15.22, which exposed the issue. Updating to a newer version (.23) did nothing to fix the issue.

  Update: Installing the kernels did not fix the issue either:
  3.5.0-16.24, 3.5.0-16.25

  ProblemType: Bug
  DistroRelease: Ubuntu 12.10
  Package: linux-image-3.5.0-13-generic 3.5.0-13.14
                                        3.5.0-14.15, 16, 17, 18, 19
                                        3.5.0-15.20, 21, 22, 23, 24
                                        3.5.0-16.25
  ProcVersionSignature: Ubuntu 3.5.0-15.23-generic 3.5.4
  Uname: Linux 3.5.0-15-generic x86_64
  ApportVersion: 2.5.2-0ubuntu4
  Architecture: amd64
  Date: Thu Sep 27 15:25:08 2012
  InstallationMedia: Kubuntu 12.10 "Quantal Quetzal" - Beta amd64 (20120913)
  ProcFB: 0 radeondrmfb
  SourcePackage: linux

  Update: Apparently the Ubuntu kernels can't handle the "vt.handoff=7" option properly, which causes the black screen.
  See my comment below for how to fix it:
  https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1057532/comments/38

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