[dpdk-dev] [PATCH] ethdev: fix crash with multiprocess

[dpdk-dev] [PATCH] ethdev: fix crash with multiprocess

[Bruce Richardson]

The data structure for the rx and tx callbacks is local to each process
since it contains function pointers and cannot be shared between
different unique binaries. However, because it is not in
rte_eth_dev_data structure, the array is not getting initialized for
secondary processes - neither is it getting appropriately resized if the
number of RX/TX queues changes. This causes crashes in secondary
processes as they dereference a null pointer in struct rte_eth_dev.

This patch fixes this by introducing an upper-bound on the number of
queues per port that can be configured, and then uses this to make the
array statically sized, thereby avoiding the crashes.

Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
---
 config/common_bsdapp          |  1 +
 config/common_linuxapp        |  1 +
 lib/librte_ether/rte_ethdev.c | 64 ++++++++++---------------------------------
 lib/librte_ether/rte_ethdev.h |  4 +--
 4 files changed, 18 insertions(+), 52 deletions(-)

diff --git a/config/common_bsdapp b/config/common_bsdapp
index 8ff4dc2..93d2f9e 100644
--- a/config/common_bsdapp
+++ b/config/common_bsdapp
@@ -137,6 +137,7 @@ CONFIG_RTE_LIBRTE_KVARGS=y
 CONFIG_RTE_LIBRTE_ETHER=y
 CONFIG_RTE_LIBRTE_ETHDEV_DEBUG=n
 CONFIG_RTE_MAX_ETHPORTS=32
+CONFIG_RTE_MAX_QUEUES_PER_PORT=256
 CONFIG_RTE_LIBRTE_IEEE1588=n
 CONFIG_RTE_ETHDEV_QUEUE_STAT_CNTRS=16
 CONFIG_RTE_ETHDEV_RXTX_CALLBACKS=y
diff --git a/config/common_linuxapp b/config/common_linuxapp
index 09a58ac..19de75f 100644
--- a/config/common_linuxapp
+++ b/config/common_linuxapp
@@ -134,6 +134,7 @@ CONFIG_RTE_LIBRTE_KVARGS=y
 CONFIG_RTE_LIBRTE_ETHER=y
 CONFIG_RTE_LIBRTE_ETHDEV_DEBUG=n
 CONFIG_RTE_MAX_ETHPORTS=32
+CONFIG_RTE_MAX_QUEUES_PER_PORT=256
 CONFIG_RTE_LIBRTE_IEEE1588=n
 CONFIG_RTE_ETHDEV_QUEUE_STAT_CNTRS=16
 CONFIG_RTE_ETHDEV_RXTX_CALLBACKS=y
diff --git a/lib/librte_ether/rte_ethdev.c b/lib/librte_ether/rte_ethdev.c
index 03fce08..9328bd8 100644
--- a/lib/librte_ether/rte_ethdev.c
+++ b/lib/librte_ether/rte_ethdev.c
@@ -741,19 +741,6 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
 			dev->data->nb_rx_queues = 0;
 			return -(ENOMEM);
 		}
-#ifdef RTE_ETHDEV_RXTX_CALLBACKS
-		dev->post_rx_burst_cbs = rte_zmalloc(
-			"ethdev->post_rx_burst_cbs",
-			sizeof(*dev->post_rx_burst_cbs) * nb_queues,
-			RTE_CACHE_LINE_SIZE);
-		if (dev->post_rx_burst_cbs == NULL) {
-			rte_free(dev->data->rx_queues);
-			dev->data->rx_queues = NULL;
-			dev->data->nb_rx_queues = 0;
-			return -ENOMEM;
-		}
-#endif
-
 	} else { /* re-configure */
 		FUNC_PTR_OR_ERR_RET(*dev->dev_ops->rx_queue_release, -ENOTSUP);
 
@@ -765,22 +752,10 @@ rte_eth_dev_rx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
 				RTE_CACHE_LINE_SIZE);
 		if (rxq == NULL)
 			return -(ENOMEM);
-#ifdef RTE_ETHDEV_RXTX_CALLBACKS
-		dev->post_rx_burst_cbs = rte_realloc(
-			dev->post_rx_burst_cbs,
-			sizeof(*dev->post_rx_burst_cbs) *
-				nb_queues, RTE_CACHE_LINE_SIZE);
-		if (dev->post_rx_burst_cbs == NULL)
-			return -ENOMEM;
-#endif
 		if (nb_queues > old_nb_queues) {
 			uint16_t new_qs = nb_queues - old_nb_queues;
 			memset(rxq + old_nb_queues, 0,
 				sizeof(rxq[0]) * new_qs);
-#ifdef RTE_ETHDEV_RXTX_CALLBACKS
-			memset(dev->post_rx_burst_cbs + old_nb_queues, 0,
-				sizeof(dev->post_rx_burst_cbs[0]) * new_qs);
-#endif
 		}
 
 		dev->data->rx_queues = rxq;
@@ -909,19 +884,6 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
 			dev->data->nb_tx_queues = 0;
 			return -(ENOMEM);
 		}
-#ifdef RTE_ETHDEV_RXTX_CALLBACKS
-		dev->pre_tx_burst_cbs = rte_zmalloc(
-			"ethdev->pre_tx_burst_cbs",
-			sizeof(*dev->pre_tx_burst_cbs) * nb_queues,
-			RTE_CACHE_LINE_SIZE);
-		if (dev->pre_tx_burst_cbs == NULL) {
-			rte_free(dev->data->tx_queues);
-			dev->data->tx_queues = NULL;
-			dev->data->nb_tx_queues = 0;
-			return -ENOMEM;
-		}
-#endif
-
 	} else { /* re-configure */
 		FUNC_PTR_OR_ERR_RET(*dev->dev_ops->tx_queue_release, -ENOTSUP);
 
@@ -933,22 +895,10 @@ rte_eth_dev_tx_queue_config(struct rte_eth_dev *dev, uint16_t nb_queues)
 				RTE_CACHE_LINE_SIZE);
 		if (txq == NULL)
 			return -ENOMEM;
-#ifdef RTE_ETHDEV_RXTX_CALLBACKS
-		dev->pre_tx_burst_cbs = rte_realloc(
-			dev->pre_tx_burst_cbs,
-			sizeof(*dev->pre_tx_burst_cbs) *
-				nb_queues, RTE_CACHE_LINE_SIZE);
-		if (dev->pre_tx_burst_cbs == NULL)
-			return -ENOMEM;
-#endif
 		if (nb_queues > old_nb_queues) {
 			uint16_t new_qs = nb_queues - old_nb_queues;
 			memset(txq + old_nb_queues, 0,
 				sizeof(txq[0]) * new_qs);
-#ifdef RTE_ETHDEV_RXTX_CALLBACKS
-			memset(dev->pre_tx_burst_cbs + old_nb_queues, 0,
-				sizeof(dev->pre_tx_burst_cbs[0]) * new_qs);
-#endif
 		}
 
 		dev->data->tx_queues = txq;
@@ -1164,6 +1114,20 @@ rte_eth_dev_configure(uint8_t port_id, uint16_t nb_rx_q, uint16_t nb_tx_q,
 		return (-EINVAL);
 	}
 
+	if (nb_rx_q > RTE_MAX_QUEUES_PER_PORT) {
+		PMD_DEBUG_TRACE(
+			"Number of RX queues requested (%u) is greater than max supported(%d)\n",
+			nb_rx_q, RTE_MAX_QUEUES_PER_PORT);
+		return (-EINVAL);
+	}
+
+	if (nb_tx_q > RTE_MAX_QUEUES_PER_PORT) {
+		PMD_DEBUG_TRACE(
+			"Number of TX queues requested (%u) is greater than max supported(%d)\n",
+			nb_tx_q, RTE_MAX_QUEUES_PER_PORT);
+		return (-EINVAL);
+	}
+
 	dev = &rte_eth_devices[port_id];
 
 	FUNC_PTR_OR_ERR_RET(*dev->dev_ops->dev_infos_get, -ENOTSUP);
diff --git a/lib/librte_ether/rte_ethdev.h b/lib/librte_ether/rte_ethdev.h
index 21aa359..725321a 100644
--- a/lib/librte_ether/rte_ethdev.h
+++ b/lib/librte_ether/rte_ethdev.h
@@ -1458,12 +1458,12 @@ struct rte_eth_dev {
 	 * User-supplied functions called from rx_burst to post-process
 	 * received packets before passing them to the user
 	 */
-	struct rte_eth_rxtx_callback **post_rx_burst_cbs;
+	struct rte_eth_rxtx_callback *post_rx_burst_cbs[RTE_MAX_QUEUES_PER_PORT];
 	/**
 	 * User-supplied functions called from tx_burst to pre-process
 	 * received packets before passing them to the driver for transmission.
 	 */
-	struct rte_eth_rxtx_callback **pre_tx_burst_cbs;
+	struct rte_eth_rxtx_callback *pre_tx_burst_cbs[RTE_MAX_QUEUES_PER_PORT];
 	uint8_t attached; /**< Flag indicating the port is attached */
 	enum rte_eth_dev_type dev_type; /**< Flag indicating the device type */
 };
-- 
2.1.0

Re: [dpdk-dev] [PATCH] ethdev: fix crash with multiprocess

[De Lara Guarch, Pablo]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Bruce Richardson
> Sent: Thursday, March 26, 2015 5:03 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH] ethdev: fix crash with multiprocess
> 
> The data structure for the rx and tx callbacks is local to each process
> since it contains function pointers and cannot be shared between
> different unique binaries. However, because it is not in
> rte_eth_dev_data structure, the array is not getting initialized for
> secondary processes - neither is it getting appropriately resized if the
> number of RX/TX queues changes. This causes crashes in secondary
> processes as they dereference a null pointer in struct rte_eth_dev.
> 
> This patch fixes this by introducing an upper-bound on the number of
> queues per port that can be configured, and then uses this to make the
> array statically sized, thereby avoiding the crashes.
> 
> Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>

Tested-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>

Re: [dpdk-dev] [PATCH] ethdev: fix crash with multiprocess

[Thomas Monjalon]

2015-03-26 17:36, De Lara Guarch, Pablo:
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Bruce Richardson
> > The data structure for the rx and tx callbacks is local to each process
> > since it contains function pointers and cannot be shared between
> > different unique binaries. However, because it is not in
> > rte_eth_dev_data structure, the array is not getting initialized for
> > secondary processes - neither is it getting appropriately resized if the
> > number of RX/TX queues changes. This causes crashes in secondary
> > processes as they dereference a null pointer in struct rte_eth_dev.
> > 
> > This patch fixes this by introducing an upper-bound on the number of
> > queues per port that can be configured, and then uses this to make the
> > array statically sized, thereby avoiding the crashes.
> > 
> > Signed-off-by: Bruce Richardson <bruce.richardson@intel.com>
> 
> Tested-by: Pablo de Lara <pablo.de.lara.guarch@intel.com>

Fixes: 4dc294158cac ("ethdev: support optional Rx and Tx callbacks")

Acked-by: Thomas Monjalon <thomas.monjalon@6wind.com>

Applied, thanks

The multiprocess design is difficult to maintain.
It would be better to have someone registered as maintainer of this part.

Re: [dpdk-dev] [PATCH] ethdev: fix crash with multiprocess

[Mcnamara, John]

> -----Original Message-----
> From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of Bruce Richardson
> Sent: Thursday, March 26, 2015 5:03 PM
> To: dev@dpdk.org
> Subject: [dpdk-dev] [PATCH] ethdev: fix crash with multiprocess

Acked-by: John McNamara <john.mcnamara@intel.com>