Partitioning guide 13.10 with UEFI firmware.

[richb]

I cannot vouch for its accuracy, but this flummoxed me with my laptop, so just disabled secure boot.

http://www.linuxbsdos.com/2014/02/05...uefi-firmware/

[SteveRiley]

That article is suspect for a couple reasons.

1. The author seems unaware that modern partitioning tools follow the 1 MB partition alignment practice. Starting the first partition on logical block 2048 (using 512-byte logical blocks) avoids large-sector misalignment. It's important because modern drives now use 4096-byte sectors, although they still report 512-byte sectors to operating systems. The "curious" 1 MB free space appearing in the partition manager reflects this.

2. The bios_grub flag is used when setting up a GPT disk on a BIOS-based machine. BIOS machines require that one partition be marked as bootable. On MBR disks, any primary partition can be flagged as bootable. On GPT disks, there is no "primary" or "extended" partition, just one type of partition. For BIOS to boot from a GPT disk, one partition needs to be marked with the bootable flag; this is frequenly called bios_grub. Note: UEFI machines do not need such a partition. I see that an update to the article mentions this partition is not needed, as is also reported in the comments.

@Richb... disabling Secure Boot doesn't flip you over to BIOS emulation mode. You're likely still running in UEFI mode.

[richb]

How about legcy boot option.

From Tapatalk

[SteveRiley]

That option enables the compatibility service module (CSM), and the firmware emulates traditional BIOS.

[oldhack]

I have done exactly this to my new laptop. I didn't really have a clue about what I was doing but on my HP machine, I completely 'wiped' Windows 8 from the drive
and repartioned the drive with GPT. I then set the bios to 'legacy' to avoid the use of the secure boot uefi feature. It did tell me it is using CSM mode (whatever that is!).

oldhack

[SteveRiley]

Legacy = CSM.

You don't have to switch to legacy mode to disable secure boot. You can disable secure boot and stay in UEFI mode. This is what I recommend so that people can begin to learn about UEFI and GPT.

[Buddlespit]

I don't think all efi's support disabling secure boot. I don't think my daughters computer did. I believe I had to use the legacy option to install her OS. This was a little over a year ago, and it was new to me, so I could be wrong.

[richb]

My point was I had to enable legacy boot because I could not get the partitioning correct for UEFI. My lack of understanding was the reason.

[SteveRiley]

I don't think all efi's support disabling secure boot. I don't think my daughters computer did. I believe I had to use the legacy option to install her OS.

If the manufacturer removes the ability to disable Secure Boot, then they will not be granted permission to use the Windows logo. Microsoft requires that a physically-present user can disable Secure Boot. Since nearly every PC us sold with the Windows logo, you should have the ability to do this. Alas, it can be poorly documented.