Re: [Qemu-devel] [RFC PATCH 2/6] hw/net/e1000: real device name is 'e1000-82540em', 'e1000' is an alias

["Dr. David Alan Gilbert" <dgilbert@redhat.com>]

* Philippe Mathieu-Daudé (f4bug@amsat.org) wrote:
> Hi David,
> 
> On 01/04/2018 01:24 PM, Dr. David Alan Gilbert wrote:
> > * Philippe Mathieu-Daudé (f4bug@amsat.org) wrote:
> >> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> >> ---
> >>  hw/net/e1000.c | 5 ++++-
> >>  1 file changed, 4 insertions(+), 1 deletion(-)
> >>
> >> diff --git a/hw/net/e1000.c b/hw/net/e1000.c
> >> index 05a00cba31..2280f7fdf9 100644
> >> --- a/hw/net/e1000.c
> >> +++ b/hw/net/e1000.c
> >> @@ -1648,6 +1648,7 @@ typedef struct E1000Info {
> >>      uint16_t   device_id;
> >>      uint8_t    revision;
> >>      uint16_t   phy_id2;
> >> +    const char **aliases;
> >>  } E1000Info;
> >>  
> >>  static void e1000_class_init(ObjectClass *klass, void *data)
> >> @@ -1695,10 +1696,11 @@ static const TypeInfo e1000_base_info = {
> >>  
> >>  static const E1000Info e1000_devices[] = {
> >>      {
> >> -        .name      = "e1000",
> >> +        .name      = "e1000-82540em",
> >>          .device_id = E1000_DEV_ID_82540EM,
> >>          .revision  = 0x03,
> >>          .phy_id2   = E1000_PHY_ID2_8254xx_DEFAULT,
> >> +        .aliases   = (const char * []) {"e1000", NULL},
> >>      },
> >>      {
> >>          .name      = "e1000-82544gc",
> >> @@ -1725,6 +1727,7 @@ static void e1000_register_types(void)
> >>  
> >>          type_info.name = info->name;
> >>          type_info.parent = TYPE_E1000_BASE;
> >> +        type_info.aliases = info->aliases;
> >>          type_info.class_data = (void *)info;
> >>          type_info.class_init = e1000_class_init;
> >>          type_info.instance_init = e1000_instance_init;
> > 
> > Can you just check that this doesn't break migration compatibility
> > either way please;  I think there's some alias code somewhere but I
> > can't remember the details.
> 
> Good point.
> 
> Something related to qdev-monitor.c?

The thing I was worrying about was when names end up in the migration
stream;  that can be a bit subtle so the only way is to just check it
doesn't break.

> > One thing I do remember that broke when it previously changed was
> > entries in PC_COMPAT_* tables like the one in hw/i386/pc_piix.c's
> > PC_COMPAT_1_3 - so check with an 'info qtree' that the property is OK.
> 
> Ok, I'll verify and think about a qtest for that.
> 
> I took this device because I wanted to test another arch than ARM (which
> strongly use FDT).
> If there is an issue migrating this particular device we can drop this
> patch for this only device, and the series still stands for the ARM/FDT.

Yes, although my concern was more general, I just had a previous case
where I had to fix e1000 downstream because of renaming; but just keep
in mind other places where names turn up, like the compatibility lists.

Dave

> Regards,
> 
> Phil.
> 



--
Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK