From a3af7c18cfe545a711e5df7491b7d6df71eba2ff Mon Sep 17 00:00:00 2001 From: Netanel Belgazal Date: Sun, 11 Jun 2017 15:42:48 +0300 Subject: 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 Signed-off-by: David S. Miller --- drivers/net/ethernet/amazon/ena/ena_netdev.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'drivers/net/ethernet/amazon/ena/ena_netdev.h') diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h index 0e22bce6239d..8828f1d6dd22 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.h +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h @@ -184,6 +184,7 @@ struct ena_stats_rx { u64 dma_mapping_err; u64 bad_desc_num; u64 rx_copybreak_pkt; + u64 empty_rx_ring; }; struct ena_ring { @@ -231,6 +232,7 @@ struct ena_ring { struct ena_stats_tx tx_stats; struct ena_stats_rx rx_stats; }; + int empty_rx_queue; } ____cacheline_aligned; struct ena_stats_dev { -- cgit v1.2.1 From 800c55cb76be6617232ef50a2be29830f3aa8e5c Mon Sep 17 00:00:00 2001 From: Netanel Belgazal Date: Sun, 11 Jun 2017 15:42:50 +0300 Subject: net: ena: bug fix in lost tx packets detection mechanism check_for_missing_tx_completions() is called from a timer task and looking for lost tx packets. The old implementation accumulate all the lost tx packets and did not check if those packets were retrieved on a later stage. This cause to a situation where the driver reset the device for no reason. Fixes: 1738cd3ed342 ("Add a driver for Amazon Elastic Network Adapters (ENA)") Signed-off-by: Netanel Belgazal Signed-off-by: David S. Miller --- drivers/net/ethernet/amazon/ena/ena_netdev.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) (limited to 'drivers/net/ethernet/amazon/ena/ena_netdev.h') diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h index 8828f1d6dd22..88b5e5612338 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.h +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h @@ -146,7 +146,18 @@ struct ena_tx_buffer { u32 tx_descs; /* num of buffers used by this skb */ u32 num_of_bufs; - /* Save the last jiffies to detect missing tx packets */ + + /* Used for detect missing tx packets to limit the number of prints */ + u32 print_once; + /* Save the last jiffies to detect missing tx packets + * + * sets to non zero value on ena_start_xmit and set to zero on + * napi and timer_Service_routine. + * + * while this value is not protected by lock, + * a given packet is not expected to be handled by ena_start_xmit + * and by napi/timer_service at the same time. + */ unsigned long last_jiffies; struct ena_com_buf bufs[ENA_PKT_MAX_BUFS]; } ____cacheline_aligned; @@ -170,7 +181,6 @@ struct ena_stats_tx { u64 napi_comp; u64 tx_poll; u64 doorbells; - u64 missing_tx_comp; u64 bad_req_id; }; -- cgit v1.2.1 From e7ff7efae5708513a795e329909ccbe2ac367b1a Mon Sep 17 00:00:00 2001 From: Netanel Belgazal Date: Sun, 11 Jun 2017 15:42:51 +0300 Subject: net: ena: update ena driver to version 1.1.7 Signed-off-by: Netanel Belgazal Signed-off-by: David S. Miller --- drivers/net/ethernet/amazon/ena/ena_netdev.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/ethernet/amazon/ena/ena_netdev.h') diff --git a/drivers/net/ethernet/amazon/ena/ena_netdev.h b/drivers/net/ethernet/amazon/ena/ena_netdev.h index 88b5e5612338..a4d3d5e21068 100644 --- a/drivers/net/ethernet/amazon/ena/ena_netdev.h +++ b/drivers/net/ethernet/amazon/ena/ena_netdev.h @@ -45,7 +45,7 @@ #define DRV_MODULE_VER_MAJOR 1 #define DRV_MODULE_VER_MINOR 1 -#define DRV_MODULE_VER_SUBMINOR 2 +#define DRV_MODULE_VER_SUBMINOR 7 #define DRV_MODULE_NAME "ena" #ifndef DRV_MODULE_VERSION -- cgit v1.2.1