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    #76
    Those of you following along at home will find the following Phoronix thread highly entertaining:

    http://phoronix.com/forums/showthread.php?76314

    I seriously wonder if the folks vociferously arguing with "mjg59" realize just who they're debating. While I continue to disagree with Matthew Garrett's ranking of the risks that Secure Boot attempts to address, he obviously understands the technology, and has a pretty good mind about the motivations of various parties, too. The ignorance and stupidity expressed by most of the other contributors to that thread is astounding.

    Comment


      #77
      More experimentation.

      Remember how, in the old days, you could confuse the heck out of the installer by incorrectly choosing where to install GRUB? Usually, the correct choice was something like /dev/sda. Rarely, was the correct choice something like /dev/sda1. In other words, most of the time, GRUB wanted to be placed in the MBR (there's that term again) of the drive, not in a partition.

      I repeated the steps above for Windows. But after that, during the Kubuntu install, I chose "manual" at the partitioning stage. First step was to shrink the fourth partition from 118 GB to 60 GB. Then I created three partitions:

      5. 20 GB - ext4 - Linux /
      6. 30 GB - ext4 - Linux home
      7. 8 GB - swap - Linux swap

      Knowing that UEFI doesn't use an MBR, and that the UEFI system partition is /dev/sda2, it would have seemed natural to select that in the drop-down list that allows you to choose where to install the boot loader. However, I didn't do that -- instead. I allowed the choice to remain /dev/sda, the default.

      The installation proceeded as normal. After it completed, I rebooted with my recovery USB because I wanted to take a look at the results. The output of efibootmgr looked correct, the contents of /EFI/boot/ubuntu on /dev/sda2 looked correct, and the contents of /etc/fstab on /dev/sda5 looked correct. Now for the test.

      I booted normally, and Kubuntu immediately came up. So for now, at least, GRUB knows how to correctly identify the EFI system partition during installation and properly add the entry for (K)ubuntu, without clobbering anything else that might already be there.

      Yet to be fixed, though, is GRUB's ability to detect Windows 8. Manually adding the menuentry portion is still required.

      Comment


        #78
        Hey, check this out!



        Yes, it actually works. You'll never believe how to get there, though. I'll see if I can get a video from my crappy mobile phone camera.

        Comment


          #79
          I feel like a monkey because I'm simply inputting all these commands and giving you the results without knowing what I'm doing. But SteveRiley, whatever you're doing seems to be working, at least partly.

          I input your commands and made the changes you gave me. After saving them, I entered the commands again and went back checked to see if they had saved. They had.

          I rebooted and lo, GRUB offered me a fourth boot option: Windows 8. When I chose it, GRUB went away and Windows Boot Manager came on, offering me the option to boot either Windows 8 or Ubuntu. If I chose the first option, I could boot into Windows 8 with SecureBoot disabled. (I checked the UEFI to make sure)

          However, if I tried to boot Ubuntu from Windows Boot Manager, I got the same error as before:

          "Windows failed to start. A recent hardware or software change might be the cause. To fix the problem:" and offered me 3 options - to use my windows installation disc and restart my computer, choose my language settings and click Next, or Click repair your computer.

          This was followed by:
          Code:
          File: \EFI\ubuntu\grubx64.efi
          Status: 0xc000007b
          Info: The application or operating system couldn't be loaded because a required file is missing or contains errors.

          Comment


            #80
            To be honest, this my first time to set up a Windows 8 + Kubuntu dual boot on UEFI, too

            In Kubuntu, please type:
            Code:
            sudo efibootmgr -b Boot0003 -B
            And then reboot. Now experiment.

            That NVRAM variable is pointing to a nonexistent boot loader, so let's get rid of it. I don't know whether this will fix the problem you've described, though.

            I'm still a little mystified why you get the "Windows Boot Manager" when you select Windows from GRUB. I'm not seeing that on my test setup.

            Comment


              #81
              I tried to run that command, konsole says:

              Code:
              boot entry: B not found
              I rebooted and everything seems the same. GRUB allows me to boot into Ubuntu, and passes me to Windows Boot Manager if I try to boot Windows 8. From Windows Boot Manager, I'm able to boot into Windows 8, but booting into Ubuntu fails.

              Comment


                #82
                Sorry, my mistake. The command should be:
                Code:
                sudo efibootmgr -b 0003 -B
                Omit the "Boot" portion.

                Comment


                  #83
                  Konsole responds:
                  Code:
                  BootCurrent: 0004
                  Timeout: 0 seconds
                  BootOrder: 0004, 0005, 2003, 2001, 2002
                  Boot0001* EFI Network 0 for IPv4 (08-9E-01-4C-16-A0)
                  Boot0002* EFI Network 0 for IPv6 (08-9E-01-4C-16-A0)
                  Boot0004* Ubuntu
                  Boot0005* Windows Boot Manager
                  Boot2001* EFI USB Device
                  Boot2002* EFI DVD/DVDROM
                  Boot2003* EFI Network
                  I don't see any changes. Everything seems as before.

                  Comment


                    #84
                    I suspect you're showing me the output of sudo efibootmgr after you ran sudo efibootmgr -b 0003 -B, because the variable "Boot0003" is now no longer in the list. That's good. I didn't think that spurious entry was causing any problem, but it's always good to keep things clean.

                    For now, you're in a usable state. Both operating systems are booting. I will think a bit more about how to streamline the Windows 8 side of things. Ideally, from GRUB you should simply launch straight into Windows, without being interrupted by another boot manager.

                    Comment


                      #85
                      I'm very sleepy... so I have to go now.. but thanks for your help SteveRiley. But I have a few questions for you:

                      Are we going ahead with the plan reset my laptop to factory conditions and then re-install Kubuntu or is that plan now redundant?

                      Should I be concerned about bootkits because SecureBoot is turned off? Should I keep SecureBoot turned off for good?

                      You seem like a big cheese... would it be possible for you see to it that these changes are rolled into GRUB/Kubuntu so that no poor soul has to go through what I have? I hope we can save a lot of people from these problems.

                      Comment


                        #86
                        Try this. Boot Windows. Then press the Windows key, type msconfig, and press Enter. Click the Boot tab. Please list each line you see in the box.

                        Comment


                          #87
                          The Boot tab in msconfig says:

                          Code:
                          Windows 8 (C:\Windows) : Current OS; Default OS
                          There is a tab for Advanced Options and other Boot options etc. below it, but if you're not interested in that, there is only this one line in the box.

                          Comment


                            #88
                            Originally posted by longnosemonkey View Post
                            Are we going ahead with the plan reset my laptop to factory conditions and then re-install Kubuntu or is that plan now redundant?
                            No. Your problem ended up being less thorny than I first imagined. No need to rebuild now.

                            Originally posted by longnosemonkey View Post
                            Should I be concerned about bootkits because SecureBoot is turned off? Should I keep SecureBoot turned off for good?
                            Opinions on this vary. I think Secure Boot is an awfully big hammer for a rather small risk. I don't think the trade-off is worth it. The biggest risks home users face are identity theft, scams, and browser-based attacks. For malware to infect the OS in the way that Secure Boot thwarts, an attacker must penetrate other security layers first.

                            Originally posted by longnosemonkey View Post
                            You seem like a big cheese... would it be possible for you see to it that these changes are rolled into GRUB/Kubuntu so that no poor soul has to go through what I have? I hope we can save a lot of people from these problems.
                            Nah, just a volunteer who likes helping others. It's already known that GRUB's OS-prober needs updating to find Windows 8. Work is underway to smooth Secure Boot support, too. It's just that, right now, you're kind of caught in the growth phase of these technologies

                            Comment


                              #89
                              In case you missed this tidbit:
                              The Boot tab in msconfig says:

                              Code:
                              Windows 8 (C:\Windows) : Current OS; Default OS
                              There is a tab for Advanced Options and other Boot options etc. below it, but if you're not interested in that, there is only this one line in the box.
                              I do re-install everything once every few years to clean up all the cruft in my computer. So if I were restore my laptop to factory conditions and start installing everything from scratch, how should I do it? What steps would I take? Or will GRUB have fixed this already?

                              Comment


                                #90
                                I saw that. Alas, your Windows Boot Manager is still a bit confused, and I'll need to think about that later. I, too, am tired now.

                                If you were to rebuild your PC, my recommendation would be the following:

                                1. Clear all existing UEFI NVRAM variables for operating system boot loaders. This is a manual step that, so far, none of the automated tools do very well.
                                2. Ensure that Secure Boot is disabled.
                                3. Install Windows 8.
                                4. Install Kubuntu.
                                5. Fix GRUB to find Windows 8.
                                6. Enjoy.

                                Essentially, I've performed the above steps twice. I now see the same thing you do, but I'm not experiencing the issue where the Windows Boot Manager appears after selecting "Windows 8" from GRUB. There's something going on between UEFI boot variables and the Windows BCD that I don't have my brain wrapped around yet.

                                Eventually, step 5 above will become unnecessary. Hopefully step 1, too.

                                Comment

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