Text manually wrapped to 80, any broken quoting is my fault - rwg

> > Hello,
> > 
> > I'm looking for better ways to check for  bhyve support / available
> > features without trying to scan through dmesg output.
> 
> >Yes, it would be very good to remove that, as it usually tries
> >to grep a non-existent file /var/run/dmesg.boot that is not
> >created until after vm_bhyve has been called from /usr/local/etc/rc.d
> >when you have things set to autostartup >in /etc/rc.conf
> 
> 
> > 
> > I notice that the following 2 sysctl's appear to be set to 1 as soon 
> > as the vmm module is loaded
> > 
> > hw.vmm.vmx.initialized: 1
> > hw.vmm.vmx.cap.unrestricted_guest: 1
> > 
> > Will these be available on both Intel & AMD processors as a way
> > to determine if the module has loaded successfully and can run guests?
> > 
> > I also see the below sysctl related to iommu.
> > 
> > hw.vmm.iommu.initialized
> > 
> > Again, will this be set to 1 as soon as the module is loaded if
> > iommu is supported, or only when it is used?
> > There also seems to be a vmm.amdvi.enable sysctl.
> > Would both these need checking or is vmm.iommu enough to
> > determine support on any processor.
> 
> >Probalby the safest way for a shell script to decide if bhyve is
> >up and running is to stat /dev/vmm, if that exists then the modules
> >have loaded and initialized and bhyve should be ready to process guests.
> 
> Hmm, I don't get /dev/vmm unless I actually have running guests.

I'll investigate that, I was pretty sure that you should get this
as soon as the vmm.ko module is finished initialzing, but you might
be right in that it takes a first vm to cause its creation.
Confirmed, /dev/vmm does not exist until the first vm
is created.

> 
> >sysctl's mentiond above would be a poor way to make this determination.
> 
> It would be nice if sysctls were better documented.

Agreed.

> If vmx.initialized is set once vmm has successfully loaded, I can't see a 
> better way of checking for bhyve support (assuming it's not Intel specific). 
> This entry definitely exists and is set to 0 if you load the module on a 
> non-supported system, and set to 1 as soon as vmm loads on my Intel test 
> system.

Given its undocumented status you would be relying on an
undocumented feature that could change in either name or
behavior, and that is not desirable.

Let me see if I can come up with something else.


-- 
Rod Grimes                                                 [email protected]
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