Re: [Qemu-devel] [PATCH 21/27] pc: add memory hotplug 440fx machine

[Igor Mammedov]

On Thu, 21 Nov 2013 15:13:12 +0100
Andreas Färber <address@hidden> wrote:

> Am 21.11.2013 06:48, schrieb Li Guang:
> > Hi, Igor
> > 
> > Igor Mammedov wrote:
> >> Add DimmBus for memory hotplug below 4Gb or above 4Gb depending
> >> on initial memory size and hotplug memory size.
> >>    
> > ...
> >> +static
> >> +void pc_hotplug_memory_init_impl(Object *owner,
> >> +                                 MemoryRegion *system_memory,
> >> +                                 ram_addr_t low_hotplug_mem_start,
> >> +                                 ram_addr_t low_hotplug_mem_end,
> >> +                                 DimmBus *hotplug_mem_bus,
> >> +                                 ram_addr_t *high_mem_end)
> >> +{
> >> +    QemuOpts *opts = qemu_opts_find(qemu_find_opts("memory-opts"),
> >> NULL);
> >> +    ram_addr_t ram_size = qemu_opt_get_size(opts, "mem", 0);
> >> +    ram_addr_t maxmem = qemu_opt_get_size(opts, "maxmem", 0);
> >> +    ram_addr_t hotplug_mem_size;
> >> +
> >> +    if (maxmem<= ram_size) {
> >> +        /* Disable ACPI migration code and creation of memory devices
> >> in SSDT */
> >>    
> > 
> > Why not give the memory that not be hot-added a chance to be placed on
> > one memory slot?
> 
> Seconded, I believe I requested that on the previous version already.
Because current initial memory allocation is a mess and this already
large series would become even more large and intrusive, so far series
it relatively not intrusive and self contained.

I believe re-factoring of initial memory to use Dimm devices should be
done later on top of infrastructure this series provides.

> Andreas
> 
> > if all memory can be hot-added and hot-removed, then we can bring in
> > more flexibility for
> > memory hotplug feature.
>