mirrors/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2025-10-31 16:48:26 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions

bnxt: don't handle XDP in netpoll

Browse source 
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: 322b87ca55 ("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>
This commit is contained in:
Jakub Kicinski 2023-07-28 13:50:20 -07:00
parent 4b31fd4d77
commit 37b61cda9c
4 changed files with 24 additions and 14 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

26
drivers/net/ethernet/broadcom/bnxt/bnxt.c
View file

@ -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,
@ -2569,12 +2571,11 @@ 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;
@ -2603,7 +2604,7 @@ 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;
}
@ -2734,7 +2735,7 @@ 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;
@ -2750,7 +2751,7 @@ 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)
@ -2780,7 +2781,8 @@ 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,
@ -2810,7 +2812,7 @@ 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);
@ -9429,6 +9431,8 @@ 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;

2
drivers/net/ethernet/broadcom/bnxt/bnxt.h
View file

@ -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;

8
drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.c
View file

@ -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];

2
drivers/net/ethernet/broadcom/bnxt/bnxt_xdp.h
View file

@ -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);