| Message ID | 1459371873-3939-1-git-send-email-per.forlin@gmail.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Kalle Valo |
| Headers | show |
2016-03-30 23:04 GMT+02:00 <per.forlin@gmail.com>: > From: Per Forlin <per.forlin@gmail.com> > > The pend_8021x_cnt gets into a state where it's not being decreased. > When the brcmf_netdev_wait_pend8021x is called it will timeout > because there are no pending packets to be consumed. There is no > easy way of getting out of this state once it has happened. > Preventing the counter from being increased in case of dropped > packets seem like a reasonable solution. > > > Log showing overflow txq and increased cnt: > > // Extra debug prints > brcmfmac: [brcmf_netdev_wait_pend8021x] pend_8021x_cnt == 0 > brcmfmac: [brcmf_netdev_start_xmit] pend_8021x_cnt == 1 > brcmfmac: [brcmf_netdev_start_xmit] pend_8021x_cnt == 2 > > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > brcmfmac: brcmf_sdio_bus_txdata: out of bus->txq !!! > > // Extra debug prints > brcmfmac: [brcmf_netdev_start_xmit] pend_8021x_cnt == 3 > brcmfmac: [brcmf_netdev_start_xmit] pend_8021x_cnt == 4 > brcmfmac: [brcmf_netdev_wait_pend8021x] pend_8021x_cnt == 4 > > WARNING: at .../brcmfmac/core.c:1289 brcmf_netdev_wait_pend8021x > (warn_slowpath_common) > (warn_slowpath_null) > (brcmf_netdev_wait_pend8021x [brcmfmac]) > (send_key_to_dongle [brcmfmac]) > (brcmf_cfg80211_del_key [brcmfmac]) > (nl80211_del_key [cfg80211]) > (genl_rcv_msg) > (netlink_rcv_skb) > (genl_rcv) > (netlink_unicast) > (netlink_sendmsg) > (sock_sendmsg) > (___sys_sendmsg) > (__sys_sendmsg) > (SyS_sendmsg) > > Signed-off-by: Per Forlin <per.forlin@gmail.com> > > --- > I came across this bug in an older kernel but it seems relevant > for the latest kernel as well. I'm not familiar with the code > but I can reproduce the issue and verify a fix for it. > This patch seems to work for my use case but I need to run some more > tests to know for sure. > > drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c > index ed9998b..8b1e30c 100644 > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c > @@ -241,7 +241,8 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff *skb, > done: > if (ret) { > ifp->stats.tx_dropped++; > + if (eh->h_proto == htons(ETH_P_PAE)) Loking closer at this the if statement here is not reliable. We may end up here without having increased the count before. On way to fix this is to add a variable that is true in case "pend_8021x_cnt" was increased or false if not. if (pend_8021x_cnt_increased) > + atomic_dec(&ifp->pend_8021x_cnt); > } else { > ifp->stats.tx_packets++; > ifp->stats.tx_bytes += skb->len; > -- > 2.1.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c index ed9998b..8b1e30c 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/core.c @@ -241,7 +241,8 @@ static netdev_tx_t brcmf_netdev_start_xmit(struct sk_buff *skb, done: if (ret) { ifp->stats.tx_dropped++; + if (eh->h_proto == htons(ETH_P_PAE)) + atomic_dec(&ifp->pend_8021x_cnt); } else { ifp->stats.tx_packets++; ifp->stats.tx_bytes += skb->len; --