On 07/09/2015 08:01 PM, Rafał Miłecki wrote:
Hello again.

After fixing user space <-> brcmfmac communication for using valid MACs:
[PATCH] brcmfmac: set wiphy's addresses to provide valid MACs
i started testing multiple interfaces.

It seems there are many bugs in brcmfmac :(

Well, you are using the device outside its capability, because brcmfmac does not properly announce interface combinations. I will submit patches for that.

So after running 3 AP interfaces and switching my STA device between them I
started seeing WARNINGs triggered by brcmf_netdev_wait_pend8021x. It was
brcmf_cfg80211_del_key that was calling above function.

The problem is that brcmf_netdev_start_xmit increases interfaces's
pend_8021x_cnt on every transmission of ETH_P_PAE but brcmf_txfinalize fails
(from time to time?) do decrease it.

There is a bug in brcmf_txfinalize that stops it from finding an interface for
the received TX transmission success. I added some debugging to brcmfmac as you
can see below and this is what I got:
[   39.394022] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c72c1dc0 on ifidx:0
[   39.413251] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c72c1dc0 on ifidx:2
[   39.421887] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c725a7c0 on ifidx:1
[   39.431720] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c6a78a00 on ifidx:0
[   39.442829] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c725a7c0 
but got invalid ifidx:1
[   39.451773] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c726ee80 on ifidx:2
[   39.460384] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c725a7c0 on ifidx:1
[   39.536224] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c725a7c0 
but got invalid ifidx:1
[   51.884737] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c714cd00 on ifidx:1
[   51.895577] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c714cd00 
but got invalid ifidx:1
[   51.904592] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c707de80 on ifidx:2
[   51.913195] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c7011e80 on ifidx:0
[   51.922900] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c725a280 on ifidx:1
[   51.933988] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c725a280 
but got invalid ifidx:1
[   51.942979] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c714cd00 on ifidx:2
[   51.951602] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c707de80 on ifidx:0
[   55.228402] brcmfmac: [brcmf_netdev_wait_pend8021x] WARNING pend_8021x_cnt:4
[   55.278395] brcmfmac: [brcmf_netdev_wait_pend8021x] WARNING pend_8021x_cnt:4
[   55.328394] brcmfmac: [brcmf_netdev_wait_pend8021x] WARNING pend_8021x_cnt:4
[   55.336211] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c7070b80 on ifidx:2
[   55.347075] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c7070b80 
and decreased pend_8021x_cnt for ifidx:2 but got negative count -1!
[   55.387991] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c6a78a00 on ifidx:1
[   55.396601] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c7070b80 on ifidx:0
[   55.406245] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c707d400 on ifidx:2
[   55.417257] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c6a78a00 
but got invalid ifidx:1
[   55.426144] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c707d400 
and decreased pend_8021x_cnt for ifidx:2 but got negative count -1!
[   55.439019] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c714cd00 on ifidx:1
[   55.447611] brcmfmac: [brcmf_netdev_start_xmit] Transmitting ETH_P_PAE 
skb:c72c2580 on ifidx:0
[   55.498397] brcmfmac: [brcmf_netdev_wait_pend8021x] WARNING pend_8021x_cnt:6
[   55.504785] brcmfmac: [brcmf_txfinalize] Finalized ETH_P_PAE skb:c714cd00 
but got invalid ifidx:1

As you can see brcmf_txfinalize fails to find interface for ifidx:1. Why is
that? It seems that drvr->iflist is an array indexed by bssidx, but
brcmf_txfinalize uses ifidx to access it. Obviously ifidx != bssidx.

This also results in decreasing pend_8021x_cnt for wrong interfaces and some
negative values.

Will you fix this?

I have some patches reworking the driver using drvr->iflist. One of the fixes involves calling brcmf_txfinalize with brcmf_if instance. I need to do more testing on those patches before submitting them. If you are willing to give them a try as well I can provide them.

Regards,
Arend

---
  drivers/net/wireless/brcm80211/brcmfmac/core.c | 22 ++++++++++++++++++----
  1 file changed, 18 insertions(+), 4 deletions(-)

diff --git a/drivers/net/wireless/brcm80211/brcmfmac/core.c 
b/drivers/net/wireless/brcm80211/brcmfmac/core.c
index 5663870..e521ce5 100644
--- a/drivers/net/wireless/brcm80211/brcmfmac/core.c
+++ b/drivers/net/wireless/brcm80211/brcmfmac/core.c
@@ -238,8 +238,10 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff 
*skb,
                goto done;
        }

-       if (eh->h_proto == htons(ETH_P_PAE))
+       if (eh->h_proto == htons(ETH_P_PAE)) {
+               pr_info("[%s] Transmitting ETH_P_PAE skb:%p on ifidx:%d\n", 
__FUNCTION__, skb, ifp->ifidx);
                atomic_inc(&ifp->pend_8021x_cnt);
+       }

        ret = brcmf_fws_process_skb(ifp, skb);

@@ -543,6 +545,8 @@ void brcmf_rx_frame(struct device *dev, struct sk_buff *skb)
                brcmf_netif_rx(ifp, skb);
  }

+static int brcmf_get_pend_8021x_cnt(struct brcmf_if *ifp);
+
  void brcmf_txfinalize(struct brcmf_pub *drvr, struct sk_buff *txp, u8 ifidx,
                      bool success)
  {
@@ -551,14 +555,24 @@ void brcmf_txfinalize(struct brcmf_pub *drvr, struct 
sk_buff *txp, u8 ifidx,
        u16 type;

        ifp = drvr->iflist[ifidx];
-       if (!ifp)
+       if (!ifp) {
+               eh = (struct ethhdr *)(txp->data);
+               type = ntohs(eh->h_proto);
+
+               if (type == ETH_P_PAE) {
+                       pr_warn("[%s] Finalized ETH_P_PAE skb:%p but got invalid 
ifidx:%d\n", __FUNCTION__, txp, ifidx);
+               }
+
                goto done;
+       }

        eh = (struct ethhdr *)(txp->data);
        type = ntohs(eh->h_proto);

        if (type == ETH_P_PAE) {
                atomic_dec(&ifp->pend_8021x_cnt);
+               if (brcmf_get_pend_8021x_cnt(ifp) < 0)
+                       pr_warn("[%s] Finalized ETH_P_PAE skb:%p and decreased 
pend_8021x_cnt for ifidx:%d but got negative count %d!\n", __FUNCTION__, txp, ifidx, 
brcmf_get_pend_8021x_cnt(ifp));
                if (waitqueue_active(&ifp->pend_8021x_wait))
                        wake_up(&ifp->pend_8021x_wait);
        }
@@ -1140,8 +1154,8 @@ int brcmf_netdev_wait_pend8021x(struct brcmf_if *ifp)
        err = wait_event_timeout(ifp->pend_8021x_wait,
                                 !brcmf_get_pend_8021x_cnt(ifp),
                                 msecs_to_jiffies(MAX_WAIT_FOR_8021X_TX));
-
-       WARN_ON(!err);
+       if (!err)
+               pr_err("[%s] WARNING pend_8021x_cnt:%d\n", __FUNCTION__, 
brcmf_get_pend_8021x_cnt(ifp));

        return !err;
  }


--
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to