Switching my system to UEFI this weekend.
 

My plan for this weekend is to switch my dual-booting system to UEFI. I plan to end up with a BIOS firmware boot menu containing two entries: one for a UEFI-booted Windows (7) and one for a UEFI-booted Slackware.

Currently, both operating systems are on legacy-mode boots. I plan to change that, and I hope this will let me get away bootloader-chaining, MBR-overwriting, and the "add Windows to lilo.conf" complexity that we're all used to dealing with.

I've read this to prepare:

UEFI boot: how does that actually work, then?

And that's "a UEFI" and not "an UEFI", right? It assume it's pronounced "Yuffie?" Like the Final Fantasy character?

slackdocs seems to be slow right now, but I did write some info about UEFI when I switched, dunno if it will be useful:
http://docs.slackware.com/howtos:sla...uefi_and_elilo

Do report how it went. I've been thinking about it for some time on my laptop.

In-place ?. That could be an interesting exercise. I had no end of trouble with Win7 (64-bit) installing on a new-build UEFI m/board - Win7 was an OEM rather than commercial copy and apparently makes quite a difference. I will also be watching with interest.

[caveat]On the system in question I have neither Slack nor elilo[/caveat]

I also switched from BIOS to UEFI on my laptop.
Switching Windows was a headache, Linux not so much.

Here is a wiki page I had written and subsequently refined: https://wiki.manjaro.org/index.php?t...m_BIOS_to_UEFI

To switch, I converted my MBR partition table to GPT using http://www.rodsbooks.com/gdisk/mbr2gpt.html

Then created a UEFI partition (fat32 - 512mb), and switched to UEFI in the firmware.

Then I booted Windows installation disk, and tried automatic repair many times, which probably did not work for me, so tried to install Windows bootloader manually onto the uefi partition using the bcdboot command.
(The following I found later: http://superuser.com/questions/46076...efi-bootloader)

After that I booted to my Linux install through chailoading via an external drive which runs Debian (and Grub), and ran the command to installing Grub-
But my laptop's firmware only recognises Windows (HP), so I had to install rEFInd for dual-booting.
https://wiki.manjaro.org/index.php?t...g_with_Windows

Alternatively, one can copy the grubx64.efi file to the Boot folder inside the EFI partition to make Grub default.
http://www.rodsbooks.com/refind/installing.html#naming

That was actually very painless.

My rig is a tower containing three hard drives: on SSD for Windows, one SSD for Linux, and an NTFS-formatted Caviar Red for storage. The motherboard is an Asus H87-Plus.

I decided to go for the "back up, wipe, install fresh" approach.

First, I disabled secure boot. It turns out that I'd had it on the entire time, and I never noticed because I was booting my operating systems in legacy mode.

Then I backed everything up, and started reinstalling Windows. I set the "CSM" setting in my firmware to "auto" and told my computer to boot the installation disc in UEFI mode. When the installation CD let me repartition the hard drives, of course I accidentally partitioned (and wiped out) the storage drive. That was fine, because I knew I would make that mistake and had backed the drive up. The rest of the installation went as normal. From Windows, I then repartitioned the storage drive, formatted the partition to NTFS, and restored the contents of the storage drive from the backup.

Then I booted my Slackware64 14.1 DVD in UEFI mode, and essentially proceeded according to README_UEFI.TXT.

I chose not to boot the kernel with KMS.

I used cgdisk to create three partitions on my Linux drive:

• An EFI System Partition, size 100M (code EF00)
• A Linux swap partition, same size as my RAM (code 8200)
• A Linux partition, default size and code

When asked whether I wanted to add an EFI boot menu entry for Slackware, I said yes. I then rebooted.

Now, the boot menu that I get when I press F8 at boot has two entries: one for Windows (actually named Windows) and one for Linux (actually named Linux). Both entries were put there by the Slackware installer.

Thanks for posting the feedback. I might actually try it soon.

booted my Slackware64 14.1 DVD in UEFI mode?
 

I was not able to UEFI boot the DVD, until I disconnected my old MBR HDD.(got freeze on grub start) Huge kernel (both 14.1 and current) also went to panic if MBR hdd was connected on boot. But with a generic kernel(from current, not tried it on 14.1) and initrd I managed to UEFI boot successfully with a mix of MBR and GPT hdds. Then just fixed all my mounts and root reference to use partition uuids(to avoid device name change problems) and now slackware64 current (on 3.14.4 generic kernel, not updated to 3.14.5 yet) boots flawlessly from UEFI. BTW Windows 7 Boot Manager always fails on MBR/GPT drive mix, but disconnecting controller channel with MBR drive from UEFI shell helps(was not the case with linux). I have more than 4 MBR partitions, maybe it causes some confusion.

Is there any reason to switch to UEFI?

To use UEFI, or not to use UEFI? answers that question.

Faster booting.

Easier multiboot setups.

How is it faster? And isn't multibooting already pretty easy?

Hardware initialization is technically and objectively faster.

I said easier!

Well, I am thinking about giving it a try but I am too lazy.

The reason to switch to UEFI and also to x86-64 is the same: because they are the future and because there are benefits. You will have to switch one day, the question is not if but when.