Re: [PATCH 4.9] brcmfmac: use correct skb freeing helper when deleting flowring

[Arend Van Spriel <arend.vanspriel@broadcom.com>]

On 27-9-2016 11:14, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
> 
> Flowrings contain skbs waiting for transmission that were passed to us
> by netif. It means we checked every one of them looking for 802.1x
> Ethernet type. When deleting flowring we have to use freeing function
> that will check for 802.1x type as well.
> 
> Freeing skbs without a proper check was leading to counter not being
> properly decreased. This was triggering a WARNING every time
> brcmf_netdev_wait_pend8021x was called.

Acked-by: Arend van Spriel <arend@broadcom.com>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
> Kalle: this isn't important enough for 4.8 as it's too late for that.
> 
> I'd like to get it for 4.9 however, as this fixes bug that could lead
> to WARNING on every add_key/del_key call. We was struggling with these
> WARNINGs for some time and this fixes one of two problems causing them.

Please mark it for stable as well.

> ---
>  drivers/net/wireless/broadcom/brcm80211/brcmfmac/flowring.c | 9 ++++++++-
>  1 file changed, 8 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/flowring.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/flowring.c
> index b16b367..d0b738d 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/flowring.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/flowring.c
> @@ -234,13 +234,20 @@ static void brcmf_flowring_block(struct brcmf_flowring *flow, u16 flowid,
>  
>  void brcmf_flowring_delete(struct brcmf_flowring *flow, u16 flowid)
>  {
> +	struct brcmf_bus *bus_if = dev_get_drvdata(flow->dev);
>  	struct brcmf_flowring_ring *ring;
> +	struct brcmf_if *ifp;
>  	u16 hash_idx;
> +	u8 ifidx;
>  	struct sk_buff *skb;
>  
>  	ring = flow->rings[flowid];
>  	if (!ring)
>  		return;
> +
> +	ifidx = brcmf_flowring_ifidx_get(flow, flowid);
> +	ifp = brcmf_get_ifp(bus_if->drvr, ifidx);
> +
>  	brcmf_flowring_block(flow, flowid, false);
>  	hash_idx = ring->hash_id;
>  	flow->hash[hash_idx].ifidx = BRCMF_FLOWRING_INVALID_IFIDX;

I am not very familiar with flowring code, but I suppose this is just
initializing the entry for later use, right?

> @@ -249,7 +256,7 @@ void brcmf_flowring_delete(struct brcmf_flowring *flow, u16 flowid)
>  
>  	skb = skb_dequeue(&ring->skblist);
>  	while (skb) {
> -		brcmu_pkt_buf_free_skb(skb);
> +		brcmf_txfinalize(ifp, skb, false);
>  		skb = skb_dequeue(&ring->skblist);
>  	}
>  
>