RE: [net-next v3 1/5] ixgbe: Ensure MAC filter was added before setting MACVLAN

[Nguyen, Anthony L]

> -Original Message-
> From: Joe Perches [mailto:j...@perches.com]
> Sent: Wednesday, July 19, 2017 3:55 AM
> Subject: Re: [net-next v3 1/5] ixgbe: Ensure MAC filter was added before 
> setting
> MACVLAN
> 
> On Tue, 2017-07-18 at 18:23 -0700, Jeff Kirsher wrote:
> > This patch adds a check to ensure that adding the MAC filter was
> > successful before setting the MACVLAN.  If it was unsuccessful,
> > propagate the error.
> []
> > diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
> > b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
> []
> > @@ -681,6 +681,7 @@ static int ixgbe_set_vf_macvlan(struct
> > ixgbe_adapter *adapter,  {
> > struct list_head *pos;
> > struct vf_macvlans *entry;
> > +   s32 retval = 0;
> 
> This function returns int, why use s32 here?
> 
> > if (index <= 1) {
> > list_for_each(pos, >vf_mvs.l) { @@ -721,14 +722,15
> @@
> > static int ixgbe_set_vf_macvlan(struct ixgbe_adapter *adapter,
> > if (!entry || !entry->free)
> > return -ENOSPC;
> >
> > -   entry->free = false;
> > -   entry->is_macvlan = true;
> > -   entry->vf = vf;
> > -   memcpy(entry->vf_macvlan, mac_addr, ETH_ALEN);
> > -
> > -   ixgbe_add_mac_filter(adapter, mac_addr, vf);
> > +   retval = ixgbe_add_mac_filter(adapter, mac_addr, vf);
> > +   if (retval >= 0) {
> > +   entry->free = false;
> > +   entry->is_macvlan = true;
> > +   entry->vf = vf;
> > +   memcpy(entry->vf_macvlan, mac_addr, ETH_ALEN);
> > +   }
> >
> > -   return 0;
> > +   return retval;
> 
> This is also backwards logic from typical style and unnecessarily indents 
> code.
> 
>   retval = ixgbe_add_mac_filter(adapter, mac_addr, vf);
>   if (retval < 0)
>   return retval;
> 
>   entry->free = false;
>   entry->is_macvlan = true;
>   entry->vf = vf;
>   memcpy(entry->vf_macvlan, mac_addr, ETH_ALEN);>
> 
>   return 0;
> }
> 
> This patch also sets the return value to a possible positive value.
> 
> Is that really desired?
> 
> The only code that seems to use a possible positive value also limits its 
> return to
> 0
> 
> static int ixgbe_uc_sync(struct net_device *netdev, const unsigned char 
> *addr) {
>   struct ixgbe_adapter *adapter = netdev_priv(netdev);
>   int ret;
> 
>   ret = ixgbe_add_mac_filter(adapter, addr, VMDQ_P(0));
> 
>   return min_t(int, ret, 0);
> }
> 

Hi Joe,

Thanks for the review.  I'll make those changes and get a v2 resubmitted.

Thanks,
Tony

Re: [net-next v3 1/5] ixgbe: Ensure MAC filter was added before setting MACVLAN

[Joe Perches]

On Tue, 2017-07-18 at 18:23 -0700, Jeff Kirsher wrote:
> This patch adds a check to ensure that adding the MAC filter was
> successful before setting the MACVLAN.  If it was unsuccessful, propagate
> the error.
[]
> diff --git a/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c 
> b/drivers/net/ethernet/intel/ixgbe/ixgbe_sriov.c
[]
> @@ -681,6 +681,7 @@ static int ixgbe_set_vf_macvlan(struct ixgbe_adapter 
> *adapter,
>  {
>   struct list_head *pos;
>   struct vf_macvlans *entry;
> + s32 retval = 0;

This function returns int, why use s32 here?
 
>   if (index <= 1) {
>   list_for_each(pos, >vf_mvs.l) {
> @@ -721,14 +722,15 @@ static int ixgbe_set_vf_macvlan(struct ixgbe_adapter 
> *adapter,
>   if (!entry || !entry->free)
>   return -ENOSPC;
>  
> - entry->free = false;
> - entry->is_macvlan = true;
> - entry->vf = vf;
> - memcpy(entry->vf_macvlan, mac_addr, ETH_ALEN);
> -
> - ixgbe_add_mac_filter(adapter, mac_addr, vf);
> + retval = ixgbe_add_mac_filter(adapter, mac_addr, vf);
> + if (retval >= 0) {
> + entry->free = false;
> + entry->is_macvlan = true;
> + entry->vf = vf;
> + memcpy(entry->vf_macvlan, mac_addr, ETH_ALEN);
> + }
>  
> - return 0;
> + return retval;

This is also backwards logic from typical style
and unnecessarily indents code.

retval = ixgbe_add_mac_filter(adapter, mac_addr, vf);
if (retval < 0)
return retval;

entry->free = false;
entry->is_macvlan = true;
entry->vf = vf;
memcpy(entry->vf_macvlan, mac_addr, ETH_ALEN);> 

return 0;
}

This patch also sets the return value to a
possible positive value.

Is that really desired?

The only code that seems to use a possible
positive value also limits its return to 0

static int ixgbe_uc_sync(struct net_device *netdev, const unsigned char *addr)
{
struct ixgbe_adapter *adapter = netdev_priv(netdev);
int ret;

ret = ixgbe_add_mac_filter(adapter, addr, VMDQ_P(0));

return min_t(int, ret, 0);
}