[PATCH net 0/5] GVE bug fixes

[PATCH net 0/5] GVE bug fixes

[David Awogbemila]

This patch series includes fixes to some bugs in the gve driver.

Catherine Sullivan (2):
  gve: Check TX QPL was actually assigned
  gve: Upgrade memory barrier in poll routine

David Awogbemila (3):
  gve: Update mgmt_msix_idx if num_ntfy changes
  gve: Add NULL pointer checks when freeing irqs.
  gve: Drop skbs with invalid queue index.

 drivers/net/ethernet/google/gve/gve_main.c | 21 ++++++++++++---------
 drivers/net/ethernet/google/gve/gve_rx.c   |  2 --
 drivers/net/ethernet/google/gve/gve_tx.c   | 10 +++++++---
 3 files changed, 19 insertions(+), 14 deletions(-)

-- 
2.31.1.751.gd2f1c929bd-goog

[PATCH net 1/5] gve: Check TX QPL was actually assigned

[David Awogbemila]

From: Catherine Sullivan <csully@google.com>

Correctly check the TX QPL was assigned and unassigned if
other steps in the allocation fail.

Fixes: f5cedc84a30d (gve: Add transmit and receive support)
Signed-off-by: Catherine Sullivan <csully@google.com>
Signed-off-by: David Awogbemila <awogbemila@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
---
 drivers/net/ethernet/google/gve/gve_tx.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c
index 6938f3a939d6..bb57c42872b4 100644
--- a/drivers/net/ethernet/google/gve/gve_tx.c
+++ b/drivers/net/ethernet/google/gve/gve_tx.c
@@ -212,10 +212,11 @@ static int gve_tx_alloc_ring(struct gve_priv *priv, int idx)
 	tx->dev = &priv->pdev->dev;
 	if (!tx->raw_addressing) {
 		tx->tx_fifo.qpl = gve_assign_tx_qpl(priv);
-
+		if (!tx->tx_fifo.qpl)
+			goto abort_with_desc;
 		/* map Tx FIFO */
 		if (gve_tx_fifo_init(priv, &tx->tx_fifo))
-			goto abort_with_desc;
+			goto abort_with_qpl;
 	}
 
 	tx->q_resources =
@@ -236,6 +237,9 @@ static int gve_tx_alloc_ring(struct gve_priv *priv, int idx)
 abort_with_fifo:
 	if (!tx->raw_addressing)
 		gve_tx_fifo_release(priv, &tx->tx_fifo);
+abort_with_qpl:
+	if (!tx->raw_addressing)
+		gve_unassign_qpl(priv, tx->tx_fifo.qpl->id);
 abort_with_desc:
 	dma_free_coherent(hdev, bytes, tx->desc, tx->bus);
 	tx->desc = NULL;
-- 
2.31.1.751.gd2f1c929bd-goog

[PATCH net 2/5] gve: Update mgmt_msix_idx if num_ntfy changes

[David Awogbemila]

If we do not get the expected number of vectors from
pci_enable_msix_range, we update priv->num_ntfy_blks but not
priv->mgmt_msix_idx. This patch fixes this so that priv->mgmt_msix_idx
is updated accordingly.

Fixes: f5cedc84a30d ("gve: Add transmit and receive support")
Signed-off-by: David Awogbemila <awogbemila@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
---
 drivers/net/ethernet/google/gve/gve_main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index 7302498c6df3..64192942ca53 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -220,6 +220,7 @@ static int gve_alloc_notify_blocks(struct gve_priv *priv)
 		int vecs_left = new_num_ntfy_blks % 2;
 
 		priv->num_ntfy_blks = new_num_ntfy_blks;
+		priv->mgmt_msix_idx = priv->num_ntfy_blks;
 		priv->tx_cfg.max_queues = min_t(int, priv->tx_cfg.max_queues,
 						vecs_per_type);
 		priv->rx_cfg.max_queues = min_t(int, priv->rx_cfg.max_queues,
-- 
2.31.1.751.gd2f1c929bd-goog

[PATCH net 3/5] gve: Add NULL pointer checks when freeing irqs.

[David Awogbemila]

When freeing notification blocks, we index priv->msix_vectors.
If we failed to allocate priv->msix_vectors (see abort_with_msix_vectors)
this could lead to a NULL pointer dereference if the driver is unloaded.

Fixes: 893ce44df565 ("gve: Add basic driver framework for Compute Engine Virtual NIC")
Signed-off-by: David Awogbemila <awogbemila@google.com>
Acked-by: Willem de Brujin <willemb@google.com>
---
 drivers/net/ethernet/google/gve/gve_main.c | 20 +++++++++++---------
 1 file changed, 11 insertions(+), 9 deletions(-)

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index 64192942ca53..21a5d058dab4 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -301,20 +301,22 @@ static void gve_free_notify_blocks(struct gve_priv *priv)
 {
 	int i;
 
-	/* Free the irqs */
-	for (i = 0; i < priv->num_ntfy_blks; i++) {
-		struct gve_notify_block *block = &priv->ntfy_blocks[i];
-		int msix_idx = i;
-
-		irq_set_affinity_hint(priv->msix_vectors[msix_idx].vector,
-				      NULL);
-		free_irq(priv->msix_vectors[msix_idx].vector, block);
+	if (priv->msix_vectors) {
+		/* Free the irqs */
+		for (i = 0; i < priv->num_ntfy_blks; i++) {
+			struct gve_notify_block *block = &priv->ntfy_blocks[i];
+			int msix_idx = i;
+
+			irq_set_affinity_hint(priv->msix_vectors[msix_idx].vector,
+					      NULL);
+			free_irq(priv->msix_vectors[msix_idx].vector, block);
+		}
+		free_irq(priv->msix_vectors[priv->mgmt_msix_idx].vector, priv);
 	}
 	dma_free_coherent(&priv->pdev->dev,
 			  priv->num_ntfy_blks * sizeof(*priv->ntfy_blocks),
 			  priv->ntfy_blocks, priv->ntfy_block_bus);
 	priv->ntfy_blocks = NULL;
-	free_irq(priv->msix_vectors[priv->mgmt_msix_idx].vector, priv);
 	pci_disable_msix(priv->pdev);
 	kvfree(priv->msix_vectors);
 	priv->msix_vectors = NULL;
-- 
2.31.1.751.gd2f1c929bd-goog

[PATCH net 4/5] gve: Upgrade memory barrier in poll routine

[David Awogbemila]

From: Catherine Sullivan <csully@google.com>

As currently written, if the driver checks for more work (via
gve_tx_poll or gve_rx_poll) before the device posts work and the
irq doorbell is not unmasked
(via iowrite32be(GVE_IRQ_ACK | GVE_IRQ_EVENT, ...)) before the device
attempts to raise an interrupt, an interrupt is lost and this could
potentially lead to the traffic being completely halted. For
example, if a tx queue has already been stopped, the driver won't get
the chance to complete work and egress will be halted.

We need a full memory barrier in the poll
routine to ensure that the irq doorbell is unmasked before the driver
checks for more work.

Fixes: f5cedc84a30d ("gve: Add transmit and receive support")
Signed-off-by: Catherine Sullivan <csully@google.com>
Signed-off-by: David Awogbemila <awogbemila@google.com>
Acked-by: Willem de Brujin <willemb@google.com>
---
 drivers/net/ethernet/google/gve/gve_main.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/google/gve/gve_main.c b/drivers/net/ethernet/google/gve/gve_main.c
index 21a5d058dab4..bbc423e93122 100644
--- a/drivers/net/ethernet/google/gve/gve_main.c
+++ b/drivers/net/ethernet/google/gve/gve_main.c
@@ -180,7 +180,7 @@ static int gve_napi_poll(struct napi_struct *napi, int budget)
 	/* Double check we have no extra work.
 	 * Ensure unmask synchronizes with checking for work.
 	 */
-	dma_rmb();
+	mb();
 	if (block->tx)
 		reschedule |= gve_tx_poll(block, -1);
 	if (block->rx)
-- 
2.31.1.751.gd2f1c929bd-goog

[PATCH net 5/5] gve: Correct SKB queue index validation.

[David Awogbemila]

SKBs with skb_get_queue_mapping(skb) == tx_cfg.num_queues should also be
considered invalid.

Fixes: f5cedc84a30d ("gve: Add transmit and receive support")
Signed-off-by: David Awogbemila <awogbemila@google.com>
Acked-by: Willem de Brujin <willemb@google.com>
---
 drivers/net/ethernet/google/gve/gve_tx.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/google/gve/gve_tx.c b/drivers/net/ethernet/google/gve/gve_tx.c
index bb57c42872b4..3e04a3973d68 100644
--- a/drivers/net/ethernet/google/gve/gve_tx.c
+++ b/drivers/net/ethernet/google/gve/gve_tx.c
@@ -593,7 +593,7 @@ netdev_tx_t gve_tx(struct sk_buff *skb, struct net_device *dev)
 	struct gve_tx_ring *tx;
 	int nsegs;
 
-	WARN(skb_get_queue_mapping(skb) > priv->tx_cfg.num_queues,
+	WARN(skb_get_queue_mapping(skb) >= priv->tx_cfg.num_queues,
 	     "skb queue index out of range");
 	tx = &priv->tx[skb_get_queue_mapping(skb)];
 	if (unlikely(gve_maybe_stop_tx(tx, skb))) {
-- 
2.31.1.751.gd2f1c929bd-goog

Re: [PATCH net 0/5] GVE bug fixes

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (refs/heads/master):

On Mon, 17 May 2021 14:08:10 -0700 you wrote:
> This patch series includes fixes to some bugs in the gve driver.
> 
> Catherine Sullivan (2):
>   gve: Check TX QPL was actually assigned
>   gve: Upgrade memory barrier in poll routine
> 
> David Awogbemila (3):
>   gve: Update mgmt_msix_idx if num_ntfy changes
>   gve: Add NULL pointer checks when freeing irqs.
>   gve: Drop skbs with invalid queue index.
> 
> [...]

Here is the summary with links:
  - [net,1/5] gve: Check TX QPL was actually assigned
    https://git.kernel.org/netdev/net/c/5aec55b46c62
  - [net,2/5] gve: Update mgmt_msix_idx if num_ntfy changes
    https://git.kernel.org/netdev/net/c/e96b491a0ffa
  - [net,3/5] gve: Add NULL pointer checks when freeing irqs.
    https://git.kernel.org/netdev/net/c/5218e919c8d0
  - [net,4/5] gve: Upgrade memory barrier in poll routine
    https://git.kernel.org/netdev/net/c/f81781835f0a
  - [net,5/5] gve: Correct SKB queue index validation.
    https://git.kernel.org/netdev/net/c/fbd4a28b4fa6

You are awesome, thank you!
--
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html