diff options
| author | Netanel Belgazal <netanel@amazon.com> | 2017-06-11 15:42:48 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-06-11 16:36:46 -0400 |
| commit | a3af7c18cfe545a711e5df7491b7d6df71eba2ff (patch) | |
| tree | eb7c182c442a68f6c11d4b675df977ceb134b240 /drivers/net/ethernet/amazon/ena/ena_ethtool.c | |
| parent | 0857d92f71b6cb75281fde913554b2d5436c394b (diff) | |
| download | op-kernel-dev-a3af7c18cfe545a711e5df7491b7d6df71eba2ff.zip op-kernel-dev-a3af7c18cfe545a711e5df7491b7d6df71eba2ff.tar.gz | |
net: ena: fix theoretical Rx hang on low memory systems
For the rare case where the device runs out of free rx buffer
descriptors (in case of pressure on kernel memory),
and the napi handler continuously fail to refill new Rx descriptors
until device rx queue totally runs out of all free rx buffers
to post incoming packet, leading to a deadlock:
* The device won't send interrupts since all the new
Rx packets will be dropped.
* The napi handler won't try to allocate new Rx descriptors
since allocation is part of NAPI that's not being invoked any more
The fix involves detecting this scenario and rescheduling NAPI
(to refill buffers) by the keepalive/watchdog task.
Fixes: 1738cd3ed342 ("Add a driver for Amazon Elastic Network Adapters (ENA)")
Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/ethernet/amazon/ena/ena_ethtool.c')
| -rw-r--r-- | drivers/net/ethernet/amazon/ena/ena_ethtool.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/drivers/net/ethernet/amazon/ena/ena_ethtool.c b/drivers/net/ethernet/amazon/ena/ena_ethtool.c index 67b2338f..533b2fb 100644 --- a/drivers/net/ethernet/amazon/ena/ena_ethtool.c +++ b/drivers/net/ethernet/amazon/ena/ena_ethtool.c @@ -94,6 +94,7 @@ static const struct ena_stats ena_stats_rx_strings[] = { ENA_STAT_RX_ENTRY(dma_mapping_err), ENA_STAT_RX_ENTRY(bad_desc_num), ENA_STAT_RX_ENTRY(rx_copybreak_pkt), + ENA_STAT_RX_ENTRY(empty_rx_ring), }; static const struct ena_stats ena_stats_ena_com_strings[] = { |
