Do I need a /boot partition if I use /boot/efi?

[jmarkd...@gmail.com]

I am working on custom partition configs to boot qubes into an nvMe drive and was wondering if, when using efi boot, I still need /boot. The help screen just states that efi boot needs to be >200mb and /boot needs to be >=500 mb. I took this as meaning it needs both but now I got to thinking maybe it needs just the efi boot?

If so, and it's the only boot partition, should it be 500mb or is 200 enough for efi boot?

[Marek Marczykowski-Górecki]

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On Mon, Jul 25, 2016 at 06:08:48AM -0700, jmarkd...@gmail.com wrote:
> I am working on custom partition configs to boot qubes into an nvMe drive and was wondering if, when using efi boot, I still need /boot. The help screen just states that efi boot needs to be >200mb and /boot needs to be >=500 mb. I took this as meaning it needs both but now I got to thinking maybe it needs just the efi boot?

On EFI boot, only /boot/efi needs to be a separate partition.

> If so, and it's the only boot partition, should it be 500mb or is 200 enough for efi boot?

In theory 200M should be enough, but its close, so better have 500M:
Every kernel uses about 5MB (vmlinuz) + up to 50MB (initramfs). By
default Qubes allows having last 3 kernels. This gives 165MB + some much
smaller files (like xen.efi or xen.cfg).

- --
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
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[jmarkd...@gmail.com]

So this could be on my end. But in 3.1 I have to install /boot and /boot/efi. Otherwise it would not let me install. It does boot which is cool.

On 3.2 I can install /boot or /boot/efi, or both, and it won't boot(cant find the drive).

Tomorrow I will try and update 3.1 kernel to 3.2 and see if it still works.

[jmarkd...@gmail.com]

So for what it's worth, I upgraded from 3.1 to 3.2 and was still able to boot from efi. Doing a clean install with 3.2 would not boot at all(without moving /boot or /boot/efi to a usb). So there must be something in the 3.2 installer that is different from 3.1 preventing this from working.

Another interesting thing happened. Previous 3.2 installations would show dom0 as having 4gig of ram(i have 16) I assumed this was just the amount assigned to dom0 but after upgrading 3.1 to 3.2 dom0 now shows my full 16 gigs of ram and subtracts from that total when a vm uses the ram.

I had been having lots of memory issues/crashing/rebooting with previous 3.2 installations that do not seem to happen anymore. So something about the 3.2 install was buggy.

Other issues I've noticed:
Fresh 3.1 install I get an error at boot about no BGRT. 3.2 did not have this error.
Fresh 3.2 install had boot errors for no-efi_memmap and erst not enabled. 3.1 did not.

Upgraded 3.1 to 3.2 has BGRT, efi_memmap, and erst errors at boot.

I hope any of this info is useful.