Re: [Qemu-devel] [PATCH] check if we have space left for hotplugged memory

["Michael S. Tsirkin" <mst@redhat.com>]

On Wed, Jun 25, 2014 at 05:01:04PM +0800, Hu Tao wrote:
> If pc-dimm is specified on qemu command line, but only with
> -m size (aka not -m size,maxmem,slots) then qemu will core dump.
> 
> This patch fixes the problem.
> 
> Signed-off-by: Hu Tao <hutao@cn.fujitsu.com>
> ---
>  hw/i386/pc.c     | 5 +++++
>  hw/mem/pc-dimm.c | 5 +++++
>  2 files changed, 10 insertions(+)
> 
> diff --git a/hw/i386/pc.c b/hw/i386/pc.c
> index 2cf22b1..1a0d96e 100644
> --- a/hw/i386/pc.c
> +++ b/hw/i386/pc.c
> @@ -1566,6 +1566,11 @@ static void pc_dimm_plug(HotplugHandler *hotplug_dev,
>          goto out;
>      }
>  
> +    if (memory_region_size(&pcms->hotplug_memory) == 0) {
> +        error_setg(&local_err, "no space left for hotplugged memory.");
> +        goto out;
> +    }
> +
>      addr = pc_dimm_get_free_addr(pcms->hotplug_memory_base,
>                                   memory_region_size(&pcms->hotplug_memory),
>                                   !addr ? NULL : &addr,


Why two errors in two places?

> diff --git a/hw/mem/pc-dimm.c b/hw/mem/pc-dimm.c
> index ad176b7..59ed9c0 100644
> --- a/hw/mem/pc-dimm.c
> +++ b/hw/mem/pc-dimm.c
> @@ -146,6 +146,11 @@ uint64_t pc_dimm_get_free_addr(uint64_t address_space_start,
>      uint64_t new_addr, ret = 0;
>      uint64_t address_space_end = address_space_start + address_space_size;
>  
> +    if (address_space_size == 0) {
> +        error_setg(errp, "no space left for hotplugged memory.");
> +        goto out;
> +    }
> +
>      assert(address_space_end > address_space_size);
>      object_child_foreach(qdev_get_machine(), pc_dimm_built_list, &list);
>  


Didn't we want a more specific message?

> -- 
> 1.9.3