The PCI-based drivers can generate the following warning: [ 9497.776350] ------------[ cut here ]------------ [ 9497.776366] WARNING: at kernel/softirq.c:159 local_bh_enable_ip+0x7a/0xa0() [ 9497.776370] Hardware name: 05794NC [ 9497.776597] Pid: 6413, comm: hostapd Not tainted 3.3.0-4.fc16.x86_64 #1 [ 9497.776601] Call Trace: [ 9497.776612] [<ffffffff81057b1f>] warn_slowpath_common+0x7f/0xc0 [ 9497.776633] [<ffffffffa034a099>] ? rtl_pci_reset_trx_ring+0x199/0x230 [rtlwifi] [ 9497.776640] [<ffffffff81057b7a>] warn_slowpath_null+0x1a/0x20 [ 9497.776646] [<ffffffff8105f06a>] local_bh_enable_ip+0x7a/0xa0 [ 9497.776654] [<ffffffff815f3ef6>] _raw_spin_unlock_bh+0x16/0x20 [ 9497.776671] [<ffffffffa03e50de>] destroy_conntrack+0x9e/0x120 [nf_conntrack] [ 9497.776681] [<ffffffff81511847>] nf_conntrack_destroy+0x17/0x20 [ 9497.776689] [<ffffffff814d9c85>] skb_release_head_state+0xe5/0x120 [ 9497.776695] [<ffffffff814d98b6>] __kfree_skb+0x16/0xa0 [ 9497.776700] [<ffffffff814d9a35>] kfree_skb+0x45/0xc0 [ 9497.776717] [<ffffffffa034a099>] rtl_pci_reset_trx_ring+0x199/0x230 [rtlwifi] [ 9497.776734] [<ffffffffa034a155>] rtl_pci_start+0x25/0x1d0 [rtlwifi] [ 9497.776750] [<ffffffffa03440b5>] rtl_op_start+0x55/0x90 [rtlwifi] [ 9497.776785] [<ffffffffa02c4956>] ieee80211_do_open+0x296/0xa10 [mac80211] [ 9497.776794] [<ffffffff815f7ddd>] ? notifier_call_chain+0x4d/0x70 [ 9497.776828] [<ffffffffa02c513d>] ieee80211_open+0x6d/0x80 [mac80211] [ 9497.776836] [<ffffffff814e8b3f>] __dev_open+0x8f/0xe0 [ 9497.776842] [<ffffffff814e8de1>] __dev_change_flags+0xa1/0x180 [ 9497.776847] [<ffffffff814e8f78>] dev_change_flags+0x28/0x70 [ 9497.776856] [<ffffffff8154e99d>] devinet_ioctl+0x61d/0x7b0 [ 9497.776863] [<ffffffff8154ef55>] inet_ioctl+0x75/0x90 [ 9497.776870] [<ffffffff814cdd50>] sock_do_ioctl+0x30/0x70 [ 9497.776876] [<ffffffff814cee09>] sock_ioctl+0x79/0x2f0 [ 9497.776885] [<ffffffff81193498>] do_vfs_ioctl+0x98/0x550 [ 9497.776891] [<ffffffff811939e1>] sys_ioctl+0x91/0xa0 [ 9497.776897] [<ffffffff815fc029>] system_call_fastpath+0x16/0x1b [ 9497.776902] ---[ end trace 22886c442489082d ]--- The cause is due to calling kfree_skb() with interrupts disabled. This bug is discussed in https://bugzilla.redhat.com/show_bug.cgi?id=797709. Reported-and-Tested by: Ivan Ivanovich <iivanich@xxxxxxxxx> Signed-off-by: Larry Finger <Larry.Finger@xxxxxxxxxxxx> --- John, Although this bug has been in rtlwifi from the beginning, it only seems to be active when the device is used as an AP. I thought about adding Stable to the Cc list, but changed my mind. Please push this for 3.6. Larry --- Index: wireless-testing/drivers/net/wireless/rtlwifi/pci.c =================================================================== --- wireless-testing.orig/drivers/net/wireless/rtlwifi/pci.c +++ wireless-testing/drivers/net/wireless/rtlwifi/pci.c @@ -1273,17 +1273,18 @@ int rtl_pci_reset_trx_ring(struct ieee80 *after reset, release previous pending packet, *and force the tx idx to the first one */ - spin_lock_irqsave(&rtlpriv->locks.irq_th_lock, flags); for (i = 0; i < RTL_PCI_MAX_TX_QUEUE_COUNT; i++) { if (rtlpci->tx_ring[i].desc) { struct rtl8192_tx_ring *ring = &rtlpci->tx_ring[i]; while (skb_queue_len(&ring->queue)) { - struct rtl_tx_desc *entry = - &ring->desc[ring->idx]; - struct sk_buff *skb = - __skb_dequeue(&ring->queue); + struct rtl_tx_desc *entry; + struct sk_buff *skb; + spin_lock_irqsave(&rtlpriv->locks.irq_th_lock, + flags); + entry = &ring->desc[ring->idx]; + skb = __skb_dequeue(&ring->queue); pci_unmap_single(rtlpci->pdev, rtlpriv->cfg->ops-> get_desc((u8 *) @@ -1291,15 +1292,15 @@ int rtl_pci_reset_trx_ring(struct ieee80 true, HW_DESC_TXBUFF_ADDR), skb->len, PCI_DMA_TODEVICE); - kfree_skb(skb); ring->idx = (ring->idx + 1) % ring->entries; + spin_unlock_irqrestore(&rtlpriv->locks.irq_th_lock, + flags); + kfree_skb(skb); } ring->idx = 0; } } - spin_unlock_irqrestore(&rtlpriv->locks.irq_th_lock, flags); - return 0; } -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
