Re: [PATCH v1] net/core: support runtime PM on net_device

["Bjørn Mork" <bjorn@mork.no>]

Ming Lei <ming.lei@canonical.com> writes:
> On Thu, Oct 18, 2012 at 4:29 PM, Bjørn Mork <bjorn@mork.no> wrote:
>> Ming Lei <ming.lei@canonical.com> writes:
>>
>>> In ioctl path on net_device, the physical deivce is often
>>> touched, but the physical device may have been put into runtime
>>> suspend state already, so cause some utilitis(ifconfig, ethtool,
>>> ...) to return failure in this situation.
>>
>> I have to as the stupid questions again, sorry...
>>
>> Just wondering, isn't that really a driver problem?  The driver will
>
> It is or not, :-)
>
>> know whether or not hardware access is required, and should wake up the
>
> The netcore knows that first,  doesn't it？

Really? Does netcore know which ioctls the driver can handle without
waking the device?  You can of course do an educated guess, but I really
hate guesswork if there is a real answer somewhere else...

>> device if necessary.  Unless I misunderstand something here, this seems
>> like papering over driver bugs?
>
> Suppose it is driver bug, and basically most network drivers don't consider
> that, and we can fix that in netcore generally, so why bother all drivers to do
> that?

Because bugs are supposed to be fixed and not hidden?

Note that I am not claiming this is a bug.  That is still an open
question as far as I can see.



Bjørn