bhyve uefi="csm"

Rodney W. Grimes freebsd-rwg at
Mon Oct 22 17:14:12 UTC 2018

> Rodney W. Grimes wrote:
> > > Can you tell us a bit about your set up, like are you using helper scripts like libvirt?
> > > To answer the question you asked when I run a vm with the CSM firmware it works for me.
> > 
> > You should always be able to boot a vm that uses
> > and boots with the non CSM uefi firmware with the
> > CSM version of the firmware, failures may start
> > to show up if your booting something that is
> > either purely legacy, or efi aware but falls
> > back to csm because it didnt like something.
> If my goal were to boot FreeDOS in bhyve, would that be ever possible?

Today no, due to the fact we do not have a ATA/legacy
emulation, but rather only ahci disk emultaion, though
I would be wrong on that point if FreeDOS has an ahci
disk driver.

This goal is on my "want" list for bhyve to be able
to do.   THere is a GSOC ata driver emulation that
works some, but I do not think it can accomplish
this task at this time.

I do not know if the CSM code is up to this task
either, but it should be.

> > The older ED2K uefi that we are using and
> > some of the hatchetry that was used to craft
> > its CSM are in a poor state and could use
> > some love. 

Rod Grimes                                                 rgrimes at

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