Re: [libvirt] [PATCHv8 1/7] bhyve: Support /domain/bootloader configuration for non-FreeBSD guests.

On Tue, Nov 11, 2014 at 10:40 AM, Michal Privoznik <mprivozn(a)redhat.com&gt; wrote: > On 11.11.2014 16:17, Conrad Meyer wrote: >> >> On Tue, Nov 11, 2014 at 9:52 AM, Michal Privoznik <mprivozn(a)redhat.com&gt; >> wrote: >>> One of the things I'm worried about is, if the boot args are not >>> specified >>> we properly add memory configured in domain XML. >>> >>> However, IIUC the memory amount can be overridden with boot args. Is that >>> expected? >> >> >> Yes. If you use bootloader_args, you get exactly what you ask for and no >> more. > > > Well, if one is modifying XML to change booloader_args already he can change > the memory amount there too. What I'm trying to say is, we should add '-m > def->mem.max_balloon' unconditionally. Or do you intend to give users so > much freedom? I worried it can bite us later when libvirt fails to see the > real amount of memory that domain has. I think also bhyve(8) itself will be unhappy. The man page specifies: """ -m size[K|k|M|m|G|g|T|t] Guest physical memory size in bytes. This must be the same size that was given to bhyveload(8). """ However, I think the messaging around bootloader_args for bhyve / bhyveload is and should remain: "if you need this, you're on your own and need to specify *everything* manually." We expect most users to not need <bootloader> for bhyve at all, especially in the medium-term future, and even fewer users to need <bootloader_args>. IMO, as a user it is more surprising to get additional arguments prepended to the arguments I have specified than to have them passed through unmodified. And we would have to prepend or otherwise shove the -m flag in the middle somewhere. I think it is probably too much magic.