net/vmxnet3: reallocate shared memzone on re-config

When adding a DPDK port to ovs-vswitchd with DPDK, the vmxnet3 device
fails to activate due to mismatched magic number.  This failure causes
following operations to run: start the port, stop the port,
reconfigure and re-start the port.

During reconfigure, if there is an existing memzone, driver will reuse
it. But reconfigure may request different number of Tx/Rx queues.
This results in a memzone with wrong size and potential invalid memory
access.

To fix this, free the memzone if found and reserve a new one.

Signed-off-by: Yong Wang <yongwang@vmware.com>
Reviewed-by: Guolin Yang <gyang@vmware.com>
Reviewed-by: Daniele Di Proietto <ddiproietto@vmware.com>
Tested-by: Daniele Di Proietto <ddiproietto@vmware.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>

diff --git a/drivers/net/vmxnet3/vmxnet3_ethdev.c b/drivers/net/vmxnet3/vmxnet3_ethdev.c
index bbbfd9c..3a4c777 100644 (file)
--- a/drivers/net/vmxnet3/vmxnet3_ethdev.c
+++ b/drivers/net/vmxnet3/vmxnet3_ethdev.c
@@ -131,7 +131,8 @@ static const struct eth_dev_ops vmxnet3_eth_dev_ops = {
 
 static const struct rte_memzone *
 gpa_zone_reserve(struct rte_eth_dev *dev, uint32_t size,
-                const char *post_string, int socket_id, uint16_t align)
+                const char *post_string, int socket_id,
+                uint16_t align, bool reuse)
 {
        char z_name[RTE_MEMZONE_NAMESIZE];
        const struct rte_memzone *mz;
@@ -140,6 +141,13 @@ gpa_zone_reserve(struct rte_eth_dev *dev, uint32_t size,
                 dev->driver->pci_drv.driver.name, dev->data->port_id, post_string);
 
        mz = rte_memzone_lookup(z_name);
+       if (!reuse) {
+               if (mz)
+                       rte_memzone_free(mz);
+               return rte_memzone_reserve_aligned(z_name, size, socket_id,
+                                                  0, align);
+       }
+
        if (mz)
                return mz;
 
@@ -371,7 +379,7 @@ vmxnet3_dev_configure(struct rte_eth_dev *dev)
         * on current socket
         */
        mz = gpa_zone_reserve(dev, sizeof(struct Vmxnet3_DriverShared),
-                             "shared", rte_socket_id(), 8);
+                             "shared", rte_socket_id(), 8, 1);
 
        if (mz == NULL) {
                PMD_INIT_LOG(ERR, "ERROR: Creating shared zone");
@@ -384,10 +392,14 @@ vmxnet3_dev_configure(struct rte_eth_dev *dev)
 
        /*
         * Allocate a memzone for Vmxnet3_RxQueueDesc - Vmxnet3_TxQueueDesc
-        * on current socket
+        * on current socket.
+        *
+        * We cannot reuse this memzone from previous allocation as its size
+        * depends on the number of tx and rx queues, which could be different
+        * from one config to another.
         */
-       mz = gpa_zone_reserve(dev, size, "queuedesc",
-                             rte_socket_id(), VMXNET3_QUEUE_DESC_ALIGN);
+       mz = gpa_zone_reserve(dev, size, "queuedesc", rte_socket_id(),
+                             VMXNET3_QUEUE_DESC_ALIGN, 0);
        if (mz == NULL) {
                PMD_INIT_LOG(ERR, "ERROR: Creating queue descriptors zone");
                return -ENOMEM;
@@ -402,8 +414,9 @@ vmxnet3_dev_configure(struct rte_eth_dev *dev)
 
        if (dev->data->dev_conf.rxmode.mq_mode == ETH_MQ_RX_RSS) {
                /* Allocate memory structure for UPT1_RSSConf and configure */
-               mz = gpa_zone_reserve(dev, sizeof(struct VMXNET3_RSSConf), "rss_conf",
-                                     rte_socket_id(), RTE_CACHE_LINE_SIZE);
+               mz = gpa_zone_reserve(dev, sizeof(struct VMXNET3_RSSConf),
+                                     "rss_conf", rte_socket_id(),
+                                     RTE_CACHE_LINE_SIZE, 1);
                if (mz == NULL) {
                        PMD_INIT_LOG(ERR,
                                     "ERROR: Creating rss_conf structure zone");