From a8496eb81342393e4c8280a5ec27e1872a3fb9fd Mon Sep 17 00:00:00 2001 From: Netanel Belgazal Date: Thu, 9 Feb 2017 15:21:35 +0200 Subject: [PATCH] net/ena: use READ_ONCE to access completion descriptors Completion descriptors are accessed from the driver and from the device. To avoid reading the old value, use READ_ONCE macro. Signed-off-by: Netanel Belgazal Signed-off-by: David S. Miller --- drivers/net/ethernet/amazon/ena/ena_com.h | 1 + drivers/net/ethernet/amazon/ena/ena_eth_com.c | 8 ++++---- 2 files changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/net/ethernet/amazon/ena/ena_com.h b/drivers/net/ethernet/amazon/ena/ena_com.h index 509d7b8e15ab..c9b33ee5f258 100644 --- a/drivers/net/ethernet/amazon/ena/ena_com.h +++ b/drivers/net/ethernet/amazon/ena/ena_com.h @@ -33,6 +33,7 @@ #ifndef ENA_COM #define ENA_COM +#include #include #include #include diff --git a/drivers/net/ethernet/amazon/ena/ena_eth_com.c b/drivers/net/ethernet/amazon/ena/ena_eth_com.c index 539c536464a5..f999305e1363 100644 --- a/drivers/net/ethernet/amazon/ena/ena_eth_com.c +++ b/drivers/net/ethernet/amazon/ena/ena_eth_com.c @@ -45,7 +45,7 @@ static inline struct ena_eth_io_rx_cdesc_base *ena_com_get_next_rx_cdesc( cdesc = (struct ena_eth_io_rx_cdesc_base *)(io_cq->cdesc_addr.virt_addr + (head_masked * io_cq->cdesc_entry_size_in_bytes)); - desc_phase = (cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_PHASE_MASK) >> + desc_phase = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_PHASE_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_PHASE_SHIFT; if (desc_phase != expected_phase) @@ -141,7 +141,7 @@ static inline u16 ena_com_cdesc_rx_pkt_get(struct ena_com_io_cq *io_cq, ena_com_cq_inc_head(io_cq); count++; - last = (cdesc->status & ENA_ETH_IO_RX_CDESC_BASE_LAST_MASK) >> + last = (READ_ONCE(cdesc->status) & ENA_ETH_IO_RX_CDESC_BASE_LAST_MASK) >> ENA_ETH_IO_RX_CDESC_BASE_LAST_SHIFT; } while (!last); @@ -489,13 +489,13 @@ int ena_com_tx_comp_req_id_get(struct ena_com_io_cq *io_cq, u16 *req_id) * expected, it mean that the device still didn't update * this completion. */ - cdesc_phase = cdesc->flags & ENA_ETH_IO_TX_CDESC_PHASE_MASK; + cdesc_phase = READ_ONCE(cdesc->flags) & ENA_ETH_IO_TX_CDESC_PHASE_MASK; if (cdesc_phase != expected_phase) return -EAGAIN; ena_com_cq_inc_head(io_cq); - *req_id = cdesc->req_id; + *req_id = READ_ONCE(cdesc->req_id); return 0; }