Re: [PATCH 05/14] hw/i386/vmport: Report VMX type in CMD_GETVERSION

[Michael S. Tsirkin]

On Tue, Mar 10, 2020 at 02:25:28PM +0200, Liran Alon wrote:
> 
> On 10/03/2020 14:14, Michael S. Tsirkin wrote:
> > On Tue, Mar 10, 2020 at 01:54:02AM +0200, Liran Alon wrote:
> > > As can be seen from VmCheck_GetVersion() in open-vm-tools code,
> > > CMD_GETVERSION should return VMX type in ECX register.
> > > 
> > > Default is to fake host as VMware ESX server. But user can control
> > > this value by "-global vmport.vmx-type=X".
> > > 
> > > Reviewed-by: Nikita Leshenko <address@hidden>
> > > Signed-off-by: Liran Alon <address@hidden>
> > > ---
> > >   hw/i386/vmport.c | 13 +++++++++++++
> > >   1 file changed, 13 insertions(+)
> > > 
> > > diff --git a/hw/i386/vmport.c b/hw/i386/vmport.c
> > > index a2c8ff4b59cf..c03f57f2f636 100644
> > > --- a/hw/i386/vmport.c
> > > +++ b/hw/i386/vmport.c
> > > @@ -36,6 +36,15 @@
> > >   #define VMPORT_ENTRIES 0x2c
> > >   #define VMPORT_MAGIC   0x564D5868
> > > +typedef enum {
> > > +   VMX_TYPE_UNSET = 0,
> > > +   VMX_TYPE_EXPRESS,    /* Deprecated type used for VMware Express */
> > > +   VMX_TYPE_SCALABLE_SERVER,    /* VMware ESX server */
> > > +   VMX_TYPE_WGS,        /* Deprecated type used for VMware Server */
> > > +   VMX_TYPE_WORKSTATION,
> > > +   VMX_TYPE_WORKSTATION_ENTERPRISE /* Deprecated type used for ACE 1.x */
> > > +} VMX_Type;
> > > +
> > Is this really VMX type? And do users care what it is?
> This enum is copied from open-vm-tools source code
> (lib/include/vm_version.h). This is how it's called in VMware Tools
> terminology... Don't blame me :)

I don't even want to go look at it to check license compatibility, but
IMHO that's just another reason to avoid copying it.
Copying bad code isn't a good idea unless needed for
compatibility.


> > Also, how about friendlier string values so people don't need to
> > figure out code numbers?
> 
> I could have defined a new PropertyInfo struct in hw/core/qdev-properties.c
> for this enum and then define a proper macro in qdev-properties.h.
> But it seems like an overkill for a value that is suppose to rarely be
> changed. So I thought this should suffice for now for user-experience
> perspective.
> If you think otherwise, I can do what I just suggested above.
> 
> -Liran

I think that's better, and this allows you to use official
product names that people can relate to.

Alternatively just drop this enum completely.  As far as you are
concerned it's just a number VM executable gives together with the
version, right?  We don't even need the enum, just set it to 2 and add a
code comment saying it's esx server.


> > 
> > >   #define VMPORT(obj) OBJECT_CHECK(VMPortState, (obj), TYPE_VMPORT)
> > >   typedef struct VMPortState {
> > > @@ -46,6 +55,7 @@ typedef struct VMPortState {
> > >       void *opaque[VMPORT_ENTRIES];
> > >       uint32_t vmx_version;
> > > +    uint8_t vmx_type;
> > >   } VMPortState;
> > >   static VMPortState *port_state;
> > > @@ -114,6 +124,7 @@ 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;
> > > +    cpu->env.regs[R_ECX] = port_state->vmx_type;
> > >       return port_state->vmx_version;
> > >   }
> > > @@ -173,6 +184,8 @@ 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_UINT8("vmx-type", VMPortState, vmx_type,
> > > +                      VMX_TYPE_SCALABLE_SERVER),
> > >       DEFINE_PROP_END_OF_LIST(),
> > >   };
> > > -- 
> > > 2.20.1