diff options
| author | Sameeh Jubran <sameehj@amazon.com> | 2019-09-15 17:29:44 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-09-16 22:40:18 +0300 |
| commit | a53651ec93a8d7ab5b26c5390e0c389048b4b4b6 (patch) | |
| tree | 3cb41a30ff56472b6218a126d71cbea2097d2639 /drivers/net/ethernet/amazon | |
| parent | 81e09359b4658fde625b59da554386179af31e33 (diff) | |
| download | linux-a53651ec93a8d7ab5b26c5390e0c389048b4b4b6.tar.xz | |
net: ena: don't wake up tx queue when down
There is a race condition that can occur when calling ena_down().
The ena_clean_tx_irq() - which is a part of the napi handler -
function might wake up the tx queue when the queue is supposed
to be down (during recovery or changing the size of the queues
for example) This causes the ena_start_xmit() function to trigger
and possibly try to access the destroyed queues.
The race is illustrated below:
Flow A: Flow B(napi handler)
ena_down()
netif_carrier_off()
netif_tx_disable()
ena_clean_tx_irq()
netif_tx_wake_queue()
ena_napi_disable_all()
ena_destroy_all_io_queues()
After these flows the tx queue is active and ena_start_xmit() accesses
the destroyed queue which leads to a kernel panic.
fixes: 1738cd3ed342 (net: ena: Add a driver for Amazon Elastic Network Adapters (ENA))
Signed-off-by: Sameeh Jubran <sameehj@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/amazon')
| -rw-r--r-- | drivers/net/ethernet/amazon/ena/ena_netdev.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.c b/drivers/net/ethernet/amazon/ena/ena_netdev.c index 664e3ed97ea9..d118ed4c57ce 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.c +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.c @@ -823,7 +823,8 @@ static int ena_clean_tx_irq(struct ena_ring *tx_ring, u32 budget) above_thresh = ena_com_sq_have_enough_space(tx_ring->ena_com_io_sq, ENA_TX_WAKEUP_THRESH); - if (netif_tx_queue_stopped(txq) && above_thresh) { + if (netif_tx_queue_stopped(txq) && above_thresh && + test_bit(ENA_FLAG_DEV_UP, &tx_ring->adapter->flags)) { netif_tx_wake_queue(txq); u64_stats_update_begin(&tx_ring->syncp); tx_ring->tx_stats.queue_wakeup++; |