From: Jakub Kicinski kuba@kernel.org
[ Upstream commit 37b61cda9c1606cd8b6445d900ca9dc03185e8b6 ]
Similarly to other recently fixed drivers make sure we don't try to access XDP or page pool APIs when NAPI budget is 0. NAPI budget of 0 may mean that we are in netpoll.
This may result in running software IRQs in hard IRQ context, leading to deadlocks or crashes.
To make sure bnapi->tx_pkts don't get wiped without handling the events, move clearing the field into the handler itself. Remember to clear tx_pkts after reset (bnxt_enable_napi()) as it's technically possible that netpoll will accumulate some tx_pkts and then a reset will happen, leaving tx_pkts out of sync with reality.
Fixes: 322b87ca55f2 ("bnxt_en: add page_pool support") Reviewed-by: Andy Gospodarek gospo@broadcom.com Reviewed-by: Michael Chan michael.chan@broadcom.com Link: https://lore.kernel.org/r/20230728205020.2784844-1-kuba@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/broadcom/bnxt/bnxt.c | 26 +++++++++++-------- drivers/net/ethernet/broadcom/bnxt/bnxt.h | 2 +- drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c | 8 +++++- drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h | 2 +- 4 files changed, 24 insertions(+), 14 deletions(-)
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.c b/drivers/net/ethernet/broadcom/bnxt/bnxt.c index b499bc9c4e067..0b314bf4fbe65 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.c @@ -633,12 +633,13 @@ static netdev_tx_t bnxt_start_xmit(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; }
-static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) +static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int budget) { struct bnxt_tx_ring_info *txr = bnapi->tx_ring; struct netdev_queue *txq = netdev_get_tx_queue(bp->dev, txr->txq_index); u16 cons = txr->tx_cons; struct pci_dev *pdev = bp->pdev; + int nr_pkts = bnapi->tx_pkts; int i; unsigned int tx_bytes = 0;
@@ -688,6 +689,7 @@ static void bnxt_tx_int(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) dev_kfree_skb_any(skb); }
+ bnapi->tx_pkts = 0; WRITE_ONCE(txr->tx_cons, cons);
__netif_txq_completed_wake(txq, nr_pkts, tx_bytes, @@ -2573,12 +2575,11 @@ static int __bnxt_poll_work(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, return rx_pkts; }
-static void __bnxt_poll_work_done(struct bnxt *bp, struct bnxt_napi *bnapi) +static void __bnxt_poll_work_done(struct bnxt *bp, struct bnxt_napi *bnapi, + int budget) { - if (bnapi->tx_pkts) { - bnapi->tx_int(bp, bnapi, bnapi->tx_pkts); - bnapi->tx_pkts = 0; - } + if (bnapi->tx_pkts) + bnapi->tx_int(bp, bnapi, budget);
if ((bnapi->events & BNXT_RX_EVENT) && !(bnapi->in_reset)) { struct bnxt_rx_ring_info *rxr = bnapi->rx_ring; @@ -2607,7 +2608,7 @@ static int bnxt_poll_work(struct bnxt *bp, struct bnxt_cp_ring_info *cpr, */ bnxt_db_cq(bp, &cpr->cp_db, cpr->cp_raw_cons);
- __bnxt_poll_work_done(bp, bnapi); + __bnxt_poll_work_done(bp, bnapi, budget); return rx_pkts; }
@@ -2738,7 +2739,7 @@ static int __bnxt_poll_cqs(struct bnxt *bp, struct bnxt_napi *bnapi, int budget) }
static void __bnxt_poll_cqs_done(struct bnxt *bp, struct bnxt_napi *bnapi, - u64 dbr_type) + u64 dbr_type, int budget) { struct bnxt_cp_ring_info *cpr = &bnapi->cp_ring; int i; @@ -2754,7 +2755,7 @@ static void __bnxt_poll_cqs_done(struct bnxt *bp, struct bnxt_napi *bnapi, cpr2->had_work_done = 0; } } - __bnxt_poll_work_done(bp, bnapi); + __bnxt_poll_work_done(bp, bnapi, budget); }
static int bnxt_poll_p5(struct napi_struct *napi, int budget) @@ -2784,7 +2785,8 @@ static int bnxt_poll_p5(struct napi_struct *napi, int budget) if (cpr->has_more_work) break;
- __bnxt_poll_cqs_done(bp, bnapi, DBR_TYPE_CQ_ARMALL); + __bnxt_poll_cqs_done(bp, bnapi, DBR_TYPE_CQ_ARMALL, + budget); cpr->cp_raw_cons = raw_cons; if (napi_complete_done(napi, work_done)) BNXT_DB_NQ_ARM_P5(&cpr->cp_db, @@ -2814,7 +2816,7 @@ static int bnxt_poll_p5(struct napi_struct *napi, int budget) } raw_cons = NEXT_RAW_CMP(raw_cons); } - __bnxt_poll_cqs_done(bp, bnapi, DBR_TYPE_CQ); + __bnxt_poll_cqs_done(bp, bnapi, DBR_TYPE_CQ, budget); if (raw_cons != cpr->cp_raw_cons) { cpr->cp_raw_cons = raw_cons; BNXT_DB_NQ_P5(&cpr->cp_db, raw_cons); @@ -9433,6 +9435,8 @@ static void bnxt_enable_napi(struct bnxt *bp) cpr->sw_stats.rx.rx_resets++; bnapi->in_reset = false;
+ bnapi->tx_pkts = 0; + if (bnapi->rx_ring) { INIT_WORK(&cpr->dim.work, bnxt_dim_work); cpr->dim.mode = DIM_CQ_PERIOD_MODE_START_FROM_EQE; diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt.h b/drivers/net/ethernet/broadcom/bnxt/bnxt.h index 080e73496066b..bb95c3dc5270f 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt.h @@ -1005,7 +1005,7 @@ struct bnxt_napi { struct bnxt_tx_ring_info *tx_ring;
void (*tx_int)(struct bnxt *, struct bnxt_napi *, - int); + int budget); int tx_pkts; u8 events;
diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c index 4efa5fe6972b2..7f2f9a317d473 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c @@ -125,16 +125,20 @@ static void __bnxt_xmit_xdp_redirect(struct bnxt *bp, dma_unmap_len_set(tx_buf, len, 0); }
-void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) +void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int budget) { struct bnxt_tx_ring_info *txr = bnapi->tx_ring; struct bnxt_rx_ring_info *rxr = bnapi->rx_ring; bool rx_doorbell_needed = false; + int nr_pkts = bnapi->tx_pkts; struct bnxt_sw_tx_bd *tx_buf; u16 tx_cons = txr->tx_cons; u16 last_tx_cons = tx_cons; int i, j, frags;
+ if (!budget) + return; + for (i = 0; i < nr_pkts; i++) { tx_buf = &txr->tx_buf_ring[tx_cons];
@@ -161,6 +165,8 @@ void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) } tx_cons = NEXT_TX(tx_cons); } + + bnapi->tx_pkts = 0; WRITE_ONCE(txr->tx_cons, tx_cons); if (rx_doorbell_needed) { tx_buf = &txr->tx_buf_ring[last_tx_cons]; diff --git a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h index ea430d6961df3..5e412c5655ba5 100644 --- a/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h +++ b/drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h @@ -16,7 +16,7 @@ struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp, struct bnxt_tx_ring_info *txr, dma_addr_t mapping, u32 len, struct xdp_buff *xdp); -void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts); +void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int budget); bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, struct xdp_buff xdp, struct page *page, u8 **data_ptr, unsigned int *len, u8 *event);