On Wed, Apr 10, 2024 at 02:10:04PM +0300, Ido Schimmel wrote:
> On Tue, Apr 09, 2024 at 05:57:16AM -0700, Breno Leitao wrote:
> > It is impossible to use init_dummy_netdev together with alloc_netdev()
> > as the 'setup' argument.
> >
> > This is because alloc_netdev() initializes some fields in the net_device
> > structure, and later init_dummy_netdev() memzero them all. This causes
> > some problems as reported here:
> >
> > https://lore.kernel.org/all/20240322082336.49f11...@kernel.org/
> >
> > Split the init_dummy_netdev() function in two. Create a new function called
> > init_dummy_netdev_core() that does not memzero the net_device structure.
> > Then have init_dummy_netdev() memzero-ing and calling
> > init_dummy_netdev_core(), keeping the old behaviour.
> >
> > init_dummy_netdev_core() is the new function that could be called as an
> > argument for alloc_netdev().
> >
> > Also, create a helper to allocate and initialize dummy net devices,
> > leveraging init_dummy_netdev_core() as the setup argument. This function
> > basically simplify the allocation of dummy devices, by allocating and
> > initializing it. Freeing the device continue to be done through
> > free_netdev()
> >
> > Suggested-by: Jakub Kicinski <k...@kernel.org>
> > Signed-off-by: Breno Leitao <lei...@debian.org>
>
> Reviewed-by: Ido Schimmel <ido...@nvidia.com>
>
> We were about to submit another user of init_dummy_netdev() when I
> noticed this patch. Converted the code to use alloc_netdev_dummy() [1]
> and it seems to be working fine. Will submit after your patch is
> accepted.
Thanks. It seems that this patch is close to get accepted. Let's see...
> See a few minor comments below.
>
> [...]
>
> > +/**
> > + * init_dummy_netdev - init a dummy network device for NAPI
> > + * @dev: device to init
> > + *
> > + * This takes a network device structure and initialize the minimum
>
> s/initialize/initializes/
>
> > + * amount of fields so it can be used to schedule NAPI polls without
> > + * registering a full blown interface. This is to be used by drivers
> > + * that need to tie several hardware interfaces to a single NAPI
> > + * poll scheduler due to HW limitations.
> > + */
> > +void init_dummy_netdev(struct net_device *dev)
> > +{
> > + /* Clear everything. Note we don't initialize spinlocks
> > + * are they aren't supposed to be taken by any of the
>
> I assume you meant s/are/as/ ?
Thanks for the feedback, I agree with all of them.
Since these lines were not introduced by this patch, and this patch is
just moving code (and comments) around, I would add a new patch to the
patch series fixing the grammar errors.
