Linux Virtualization - May 2018 - [PATCH net-next v12 2/5] netvsc: refactor notifier/event handling code to use the failover framework

On Fri, 25 May 2018 16:11:47 -0700
"Samudrala, Sridhar" <sridhar.samudrala at intel.com> wrote:
> On 5/25/2018 3:34 PM, Stephen Hemminger wrote:
> > On Thu, 24 May 2018 09:55:14 -0700
> > Sridhar Samudrala <sridhar.samudrala at intel.com> wrote:
> >  
> >> --- a/drivers/net/hyperv/Kconfig
> >> +++ b/drivers/net/hyperv/Kconfig
> >> @@ -2,5 +2,6 @@ config HYPERV_NET
> >>   	tristate "Microsoft Hyper-V virtual network driver"
> >>   	depends on HYPERV
> >>   	select UCS2_STRING
> >> +	select FAILOVER  
> > When I take a working kernel config, add the patches then do
> > make oldconfig
> >
> > It is not autoselecting FAILOVER, it prompts me for it. This means
> > if user says no then a non-working netvsc device is made.  
> 
> I see
>     Generic failover module (FAILOVER) [M/y/?] (NEW)
> 
> So the user is given an option to either build as a Module or part of the
> kernel. 'n' is not an option.
With most libraries there is no prompt at all.

On 5/25/2018 4:28 PM, Stephen Hemminger wrote:
> On Fri, 25 May 2018 16:11:47 -0700
> "Samudrala, Sridhar" <sridhar.samudrala at intel.com>
wrote:
>
>> On 5/25/2018 3:34 PM, Stephen Hemminger wrote:
>>> On Thu, 24 May 2018 09:55:14 -0700
>>> Sridhar Samudrala <sridhar.samudrala at intel.com> wrote:
>>>   
>>>> --- a/drivers/net/hyperv/Kconfig
>>>> +++ b/drivers/net/hyperv/Kconfig
>>>> @@ -2,5 +2,6 @@ config HYPERV_NET
>>>>    	tristate "Microsoft Hyper-V virtual network
driver"
>>>>    	depends on HYPERV
>>>>    	select UCS2_STRING
>>>> +	select FAILOVER
>>> When I take a working kernel config, add the patches then do
>>> make oldconfig
>>>
>>> It is not autoselecting FAILOVER, it prompts me for it. This means
>>> if user says no then a non-working netvsc device is made.
>> I see
>>      Generic failover module (FAILOVER) [M/y/?] (NEW)
>>
>> So the user is given an option to either build as a Module or part of
the
>> kernel. 'n' is not an option.
> With most libraries there is no prompt at all.
Not sure what you meant by this.
Without any patches applied, i had a .config file with HYPERV_NET configured
as a module.
Then after applying the first 2 patches in this series, i did a
   make oldconfig
and i see the above prompt.

Are you saying that on some distros, 'make oldconfig creates a .config
file without any prompt and FAILOVER is not getting selected even when
HYPERV_NET
is enabled?

Sat, May 26, 2018 at 09:22:18AM CEST, sridhar.samudrala at intel.com
wrote:
>On 5/25/2018 4:28 PM, Stephen Hemminger wrote:
>> On Fri, 25 May 2018 16:11:47 -0700
>> "Samudrala, Sridhar" <sridhar.samudrala at intel.com>
wrote:
>> 
>> > On 5/25/2018 3:34 PM, Stephen Hemminger wrote:
>> > > On Thu, 24 May 2018 09:55:14 -0700
>> > > Sridhar Samudrala <sridhar.samudrala at intel.com>
wrote:
>> > > > --- a/drivers/net/hyperv/Kconfig
>> > > > +++ b/drivers/net/hyperv/Kconfig
>> > > > @@ -2,5 +2,6 @@ config HYPERV_NET
>> > > >    	tristate "Microsoft Hyper-V virtual network
driver"
>> > > >    	depends on HYPERV
>> > > >    	select UCS2_STRING
>> > > > +	select FAILOVER
>> > > When I take a working kernel config, add the patches then do
>> > > make oldconfig
>> > > 
>> > > It is not autoselecting FAILOVER, it prompts me for it. This
means
>> > > if user says no then a non-working netvsc device is made.
>> > I see
>> >      Generic failover module (FAILOVER) [M/y/?] (NEW)
>> > 
>> > So the user is given an option to either build as a Module or part
of the
>> > kernel. 'n' is not an option.
>> With most libraries there is no prompt at all.
>
>Not sure what you meant by this.
>Without any patches applied, i had a .config file with HYPERV_NET configured
>as a module.
>Then after applying the first 2 patches in this series, i did a
>  make oldconfig
>and i see the above prompt.
>
>Are you saying that on some distros, 'make oldconfig creates a .config
>file without any prompt and FAILOVER is not getting selected even when
HYPERV_NET
>is enabled?
>
>
Well the thing is that for a user, it makes no sense to select
"FAILOVER" by hand. It is a lib, so it should be only select it by a
user. It has no sense to have it turned on by hand - no lib user.
You can achieve that by simply removing "help" for the Kconfig
item. Same thing for "NET_FAILOVER".