Re: [Qemu-devel] [PATCH v2] pc: allow raising low memory via max-ram-below-4g option

[Michael S. Tsirkin]

On Wed, Jan 20, 2016 at 03:15:04PM -0200, Eduardo Habkost wrote:
> On Wed, Jan 20, 2016 at 01:34:29PM -0200, Eduardo Habkost wrote:
> [...]
> > Considering that we never supported
> >   gigabyte_align && max_ram_below_4g > 3G ||
> >   max_ram_below_4g > 3.5G
> > before, we could simply remove the MachineClass::gigabyte_align
> > field from pc_piix, and just do the following:
> > 
> > * pc > 1.7: max_ram_below_4g = 3G
> >   (equivalent to gigabyte_align=true)
> > * pc <= 1.7: max_ram_below_4g = 3.5G
> >   (equivalent to gigabyte_align=false)
> 
> Ignore the suggestion above. I forgot that gigabyte_align applies
> only if ram_size > 3.5GB (so setting max_ram_below_4g = 3G on
> pc > 1.7 wouldn't work). So, unless somebody has a suggestion
> that makes this logic simpler:

I wonder whether we should just bite the bullet and ask management to
maintain the physical memory map for us, instead of trying to give us
hints.

Thoughts?


> Reviewed-by: Eduardo Habkost <address@hidden>
>
> -- 
> Eduardo