Re: [PATCH 04/14] hw/i386/vmport: Introduce vmx-version property

[Liran Alon <liran.alon@oracle.com>]

On 10/03/2020 11:32, Michael S. Tsirkin wrote:
> On Tue, Mar 10, 2020 at 01:54:01AM +0200, Liran Alon wrote:
>> Instead of hard-coding the VMX version, make it a VMPORT object property.
>> This would allow user to control it's value via "-global vmport.vmx-version=X".
>>
>> Reviewed-by: Nikita Leshenko <nikita.leshchenko@oracle.com>
>> Signed-off-by: Liran Alon <liran.alon@oracle.com>
> More detail on why this is useful?
It's more useful than returning a hard-coded "6" as the vmx-version...
We have used it to preserve compatibility for some VMware guests that we 
run as-is on top of QEMU/KVM which expects specific vmx-version or else 
they fail to run properly.

-Liran

>
>> ---
>>   hw/i386/vmport.c | 6 +++++-
>>   1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/hw/i386/vmport.c b/hw/i386/vmport.c
>> index 7c21e56081b0..a2c8ff4b59cf 100644
>> --- a/hw/i386/vmport.c
>> +++ b/hw/i386/vmport.c
>> @@ -44,6 +44,8 @@ typedef struct VMPortState {
>>       MemoryRegion io;
>>       VMPortReadFunc *func[VMPORT_ENTRIES];
>>       void *opaque[VMPORT_ENTRIES];
>> +
>> +    uint32_t vmx_version;
>>   } VMPortState;
>>   
>>   static VMPortState *port_state;
>> @@ -112,7 +114,7 @@ static uint32_t vmport_cmd_get_version(void *opaque, uint32_t addr)
>>       X86CPU *cpu = X86_CPU(current_cpu);
>>   
>>       cpu->env.regs[R_EBX] = VMPORT_MAGIC;
>> -    return 6;
>> +    return port_state->vmx_version;
>>   }
>>   
>>   static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
>> @@ -169,6 +171,8 @@ static void vmport_realizefn(DeviceState *dev, Error **errp)
>>   }
>>   
>>   static Property vmport_properties[] = {
>> +    /* Default value taken from open-vm-tools code VERSION_MAGIC definition */
>> +    DEFINE_PROP_UINT32("vmx-version", VMPortState, vmx_version, 6),
>>       DEFINE_PROP_END_OF_LIST(),
>>   };
>>   
>> -- 
>> 2.20.1