UEFI/GPT Slackware64 14.1 install "no Linux partitions detected" error.
 

I would like to install Slackware64 14.1 on a Lenovo IdeaCenter with an i3 processor. The computer uses UEFI/GPT and has an already existing Ubuntu/Win8 dual boot setup. The idea was to run the Slackware installer from DVD and simply reformat the already existing ext4 partitions used by Ubuntu. Unfortunately, the system installer does not detect the ext4 partitions (although it does detect the swap partition). Instead, I get a "no Linux partitions detected" error from the installer.

Any ideas? UEFI/GPT is definitely not my strong suit.

Launch the installer, then a soon as logged in as "root", do not type "setup" but type:and post the results here.

If you want to ease the transcription, before typing that command you can insert an USB stick with e.g. a FAT formatted partition . lsblk will tell you its name. if it's e.g. sdb1 typeThen mount the stick on a running system and post the output of "cat lsblk.txt" and "cat gdisk.txt" or attach the files to your next post.

Thanks for the quick reply. Here is the output from lsblk.txt:
The second command kicked up the following error:
The contents of gdisk.txt is:

The command should have beed "gdisk /dev/sda/", sorry.

But to be sure, please do it again with these two commands

If you are doing what I think you are doing, the SlackWare installer
will not show you any linux installed partions until you have set up
a / partition.
I've been caught in this several times.

You will need to use gdisk to delete your old linux partition first,
then reset it to type 83. Then you can go on with the install.

Actually, what I suspect is that the partition type of /dev/sda7 and /dev/sda9 is of type 0700 as reported by gdisk. Unfortunately this is not a precise indication for the script /sbin/probe because this partition type, labeled "Basic Microsoft Data" and supposed to be used to host various Microsoft file systems, can also be used to host Linux file systems like e.g. ext4. Probably this happened during Ubuntu installation. But in the installer for Slackware version 14.1 /sbin/probe assumes that this as a partition used by Windows, of type either HPFS/NTFS, exFAT or W95 FAT32, but not a Linux partition.

The output of "gdisk /dev/sda" will confirm or infirm this assumption.

If it is confirmed you are right, the work around is to set the partition type to 8300 using either gdisk or cgdisk.

@globbertrotterdk: in case you want to use /dev/sda7 as your / partition, it's too small IMO. Either just make one single partition plus swap (the simpler IMO) or if you want a separate /home, give at least 15G to /.

On the long term, I think that an output of a lsblk command like the one I proposed in my first post would enhance the ability of /sbin/probe to properly detect Linux partitions or more accurately, partitions that are either of type Linux or currently used to host a Linux file system.

@ Didier. That is correct. I have a root partition and /home partition. I can also confirm that your supposition is correct. I have seen the type "0700" partition earlier, when I ran cgdisk to take a look. I will confirm this by running the commands again when I get a chance later today. As you think my root partition is too small, probably the best procedure is to delete the partitions and create new ones the correct size.

Yes. And that should not be risky, since partitions to be deleted are adjacent and the last ones of the drive. Just delete in that order /dev/sda9, then /dev/sda8, then /dev/sda7,then create the partitions you will actually use, of type either 8300 for Linux or 8200 for Linux swap.

Also, is your firmware set up in EFI mode? If you see a GRUB screen when booting the installer, that is the case.

It seems that you already have at least one EFI partition, probably /dev/sda2 and/or /dev/sda3 that are both equipped by a FAT32 file system. It is not completely impossible that one of them contains an EFI image used by Windows 8 and the other an EFI image used by Ubuntu.

You can check the type of these partitions with gdisk or cgdisk, and also check their content mounting them one at a time as /floppy. Do not forget to umount /floppy before running setup.

If I am correct the installer will pick the first EFI partitions it finds to equip it, else (but unlikely) if there is no EFI partition yet you will have to create one.

Of course discard all I have written above if you see a Syslinux screen at boot: that would mean that your firmware is in Legacy mode thus you won't need an EFI partition to install Slackware.

Here is the output of fdisk:
Here is the output of gdisk:
Edit----
Is the message from fdisk "Partition 1 does not start on physical sector boundary." something to worry about?

see http://www.linuxquestions.org/questi...9/#post5152432
but that's maybe too old.... better read the recent thread starting with...
http://www.linuxquestions.org/questi...0/#post5446586

Thanks for the reply. I got frustrated with this UEFI mess and figured out how to boot the box in legacy mode. I wiped the hard disk, installed Win 7 in legacy mode and then a Slackware minimal install.

Sorry to hear that; I went the other way, as UEFI is not going away. In this forum there has been a lot of info accumulating on Eufi stuff (for example: switch to uefi and slackware-on-uefi and actually once it is working it is easy to maintain. I found that getting the proper formatting of the efi-partition the most trickiest part... But saying that, I am not double booting with windows.