This is a note to let you know that I've just added the patch titled
bnxt: don't handle XDP in netpoll
to the 6.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bnxt-don-t-handle-xdp-in-netpoll.patch
and it can be found in the queue-6.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 7f31cba758d8c1d98474a38f3949a283bc4c8474
Author: Jakub Kicinski <kuba@xxxxxxxxxx>
Date: Fri Jul 28 13:50:20 2023 -0700
bnxt: don't handle XDP in netpoll
[ 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@xxxxxxxxxxxx>
Reviewed-by: Michael Chan <michael.chan@xxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20230728205020.2784844-1-kuba@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
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);
