Re: [Qemu-devel] [RFC v3 07/15] hw/arm/virt: Add memory hotplug framework

[David Hildenbrand]

On 03.07.2018 09:19, Eric Auger wrote:
> From: Shameer Kolothum <address@hidden>
> 
> This patch adds the the memory hot-plug/hot-unplug infrastructure
> in machvirt.
> 
> Signed-off-by: Eric Auger <address@hidden>
> Signed-off-by: Shameer Kolothum <address@hidden>
> Signed-off-by: Kwangwoo Lee <address@hidden>
> 
> ---
> 
> v1 -> v2:
> - s/virt_dimm_plug|unplug/virt_memory_plug|unplug
> - s/pc_dimm_memory_plug/pc_dimm_plug
> - reworded title and commit message
> - added pre_plug cb
> - don't handle get_memory_region failure anymore
> ---
>  default-configs/arm-softmmu.mak |  2 ++
>  hw/arm/virt.c                   | 68 
> ++++++++++++++++++++++++++++++++++++++++-
>  2 files changed, 69 insertions(+), 1 deletion(-)
> 
> diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
> index 834d45c..28fe8f3 100644
> --- a/default-configs/arm-softmmu.mak
> +++ b/default-configs/arm-softmmu.mak
> @@ -152,3 +152,5 @@ CONFIG_PCI_DESIGNWARE=y
>  CONFIG_STRONGARM=y
>  CONFIG_HIGHBANK=y
>  CONFIG_MUSICPAL=y
> +CONFIG_MEM_HOTPLUG=y
> +
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index 6fefb78..7190962 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -60,6 +60,8 @@
>  #include "standard-headers/linux/input.h"
>  #include "hw/arm/smmuv3.h"
>  #include "hw/acpi/acpi.h"
> +#include "hw/mem/pc-dimm.h"
> +#include "hw/mem/nvdimm.h"
>  
>  #define DEFINE_VIRT_MACHINE_LATEST(major, minor, latest) \
>      static void virt_##major##_##minor##_class_init(ObjectClass *oc, \
> @@ -1785,6 +1787,53 @@ static const CPUArchIdList 
> *virt_possible_cpu_arch_ids(MachineState *ms)
>      return ms->possible_cpus;
>  }
>  
> +static void virt_memory_pre_plug(HotplugHandler *hotplug_dev, DeviceState 
> *dev,
> +                                 Error **errp)
> +{
> +    const bool is_nvdimm = object_dynamic_cast(OBJECT(dev), TYPE_NVDIMM);
> +
> +    if (is_nvdimm) {
> +        error_setg(errp, "nvdimm is not yet supported");
> +        return;
> +    }

You mention that actual hotplug is not supported, only coldplug.
Wouldn't this be the right place to check for that? (only skimmed over
your patches, how do you handle that?)


-- 

Thanks,

David / dhildenb