From: Yang Yingliang yangyingliang@huawei.com
[ Upstream commit ddc9648db162eee556edd5222d2808fe33730203 ]
It is not allowed to call kfree_skb() or consume_skb() from hardware interrupt context or with hardware interrupts being disabled.
It should use dev_kfree_skb_irq() or dev_consume_skb_irq() instead. The difference between them is free reason, dev_kfree_skb_irq() means the SKB is dropped in error and dev_consume_skb_irq() means the SKB is consumed in normal.
skb_queue_purge() is called under spin_lock_irqsave() in hfcusb_l2l1D(), kfree_skb() is called in it, to fix this, use skb_queue_splice_init() to move the dch->squeue to a free queue, also enqueue the tx_skb and rx_skb, at last calling __skb_queue_purge() to free the SKBs afer unlock.
In tx_iso_complete(), dev_kfree_skb() is called to consume the transmitted SKB, so replace it with dev_consume_skb_irq().
Fixes: 69f52adb2d53 ("mISDN: Add HFC USB driver") Signed-off-by: Yang Yingliang yangyingliang@huawei.com Reviewed-by: Alexander Duyck alexanderduyck@fb.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/isdn/hardware/mISDN/hfcsusb.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-)
diff --git a/drivers/isdn/hardware/mISDN/hfcsusb.c b/drivers/isdn/hardware/mISDN/hfcsusb.c index c952002c6301..c49081ed5734 100644 --- a/drivers/isdn/hardware/mISDN/hfcsusb.c +++ b/drivers/isdn/hardware/mISDN/hfcsusb.c @@ -337,20 +337,24 @@ hfcusb_l2l1D(struct mISDNchannel *ch, struct sk_buff *skb) test_and_clear_bit(FLG_L2_ACTIVATED, &dch->Flags);
if (hw->protocol == ISDN_P_NT_S0) { + struct sk_buff_head free_queue; + + __skb_queue_head_init(&free_queue); hfcsusb_ph_command(hw, HFC_L1_DEACTIVATE_NT); spin_lock_irqsave(&hw->lock, flags); - skb_queue_purge(&dch->squeue); + skb_queue_splice_init(&dch->squeue, &free_queue); if (dch->tx_skb) { - dev_kfree_skb(dch->tx_skb); + __skb_queue_tail(&free_queue, dch->tx_skb); dch->tx_skb = NULL; } dch->tx_idx = 0; if (dch->rx_skb) { - dev_kfree_skb(dch->rx_skb); + __skb_queue_tail(&free_queue, dch->rx_skb); dch->rx_skb = NULL; } test_and_clear_bit(FLG_TX_BUSY, &dch->Flags); spin_unlock_irqrestore(&hw->lock, flags); + __skb_queue_purge(&free_queue); #ifdef FIXME if (test_and_clear_bit(FLG_L1_BUSY, &dch->Flags)) dchannel_sched_event(&hc->dch, D_CLEARBUSY); @@ -1344,7 +1348,7 @@ tx_iso_complete(struct urb *urb) printk("\n"); }
- dev_kfree_skb(tx_skb); + dev_consume_skb_irq(tx_skb); tx_skb = NULL; if (fifo->dch && get_next_dframe(fifo->dch)) tx_skb = fifo->dch->tx_skb;