[PATCH v5 2/2] app/testpmd: fix invalid txq number setting

[Wei Dai <wei.dai@intel.com>]

If an invalid number of TX queues is configured from testpmd run-time
command like "port config all txq number" or from --txq in the command
to start testpmd, the global variable nb_txq is updated by this invalid
value without this patch. It may cause testpmd crash. This patch refuses
invalid txq setting and keeps its last correct value.

Fixes: ce8d561418d4 ("app/testpmd: add port configuration settings")
Cc: stable@dpdk.org

Signed-off-by: Wei Dai <wei.dai@intel.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
---
 app/test-pmd/cmdline.c    |  2 ++
 app/test-pmd/parameters.c |  6 +++---
 app/test-pmd/testpmd.c    | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 app/test-pmd/testpmd.h    |  2 ++
 4 files changed, 53 insertions(+), 3 deletions(-)

diff --git a/app/test-pmd/cmdline.c b/app/test-pmd/cmdline.c
index f0623b1..6619cb8 100644
--- a/app/test-pmd/cmdline.c
+++ b/app/test-pmd/cmdline.c
@@ -1527,6 +1527,8 @@ cmd_config_rx_tx_parsed(void *parsed_result,
 			printf("Warning: Either rx or tx queues should be non zero\n");
 			return;
 		}
+		if (check_nb_txq(res->value) != 0)
+			return;
 		nb_txq = res->value;
 	}
 	else if (!strcmp(res->name, "rxd")) {
diff --git a/app/test-pmd/parameters.c b/app/test-pmd/parameters.c
index c46e734..ca2af65 100644
--- a/app/test-pmd/parameters.c
+++ b/app/test-pmd/parameters.c
@@ -932,12 +932,12 @@ launch_args_parse(int argc, char** argv)
 			}
 			if (!strcmp(lgopts[opt_idx].name, "txq")) {
 				n = atoi(optarg);
-				if (n >= 0 && n <= (int) MAX_QUEUE_ID)
+				if (n >= 0 && check_nb_txq((queueid_t)n) == 0)
 					nb_txq = (queueid_t) n;
 				else
 					rte_exit(EXIT_FAILURE, "txq %d invalid - must be"
-						  " >= 0 && <= %d\n", n,
-						  (int) MAX_QUEUE_ID);
+						  " >= 0 && <= %u\n", n,
+						  get_allowed_max_nb_txq(&pid));
 			}
 			if (!nb_rxq && !nb_txq) {
 				rte_exit(EXIT_FAILURE, "Either rx or tx queues should "
diff --git a/app/test-pmd/testpmd.c b/app/test-pmd/testpmd.c
index 4e8667d..493e028 100644
--- a/app/test-pmd/testpmd.c
+++ b/app/test-pmd/testpmd.c
@@ -586,6 +586,52 @@ check_nb_rxq(queueid_t rxq)
 	return 0;
 }
 
+/*
+ * Get the allowed maximum number of TX queues.
+ * *pid return the port id which has minimal value of
+ * max_tx_queues in all ports.
+ */
+queueid_t
+get_allowed_max_nb_txq(portid_t *pid)
+{
+	queueid_t allowed_max_txq = MAX_QUEUE_ID;
+	portid_t pi;
+	struct rte_eth_dev_info dev_info;
+
+	RTE_ETH_FOREACH_DEV(pi) {
+		rte_eth_dev_info_get(pi, &dev_info);
+		if (dev_info.max_tx_queues < allowed_max_txq) {
+			allowed_max_txq = dev_info.max_tx_queues;
+			*pid = pi;
+		}
+	}
+	return allowed_max_txq;
+}
+
+/*
+ * Check input txq is valid or not.
+ * If input txq is not greater than any of maximum number
+ * of TX queues of all ports, it is valid.
+ * if valid, return 0, else return -1
+ */
+int
+check_nb_txq(queueid_t txq)
+{
+	queueid_t allowed_max_txq;
+	portid_t pid = 0;
+
+	allowed_max_txq = get_allowed_max_nb_txq(&pid);
+	if (txq > allowed_max_txq) {
+		printf("Fail: input txq (%u) can't be greater "
+		       "than max_tx_queues (%u) of port %u\n",
+		       txq,
+		       allowed_max_txq,
+		       pid);
+		return -1;
+	}
+	return 0;
+}
+
 static void
 init_config(void)
 {
diff --git a/app/test-pmd/testpmd.h b/app/test-pmd/testpmd.h
index e815509..fe40892 100644
--- a/app/test-pmd/testpmd.h
+++ b/app/test-pmd/testpmd.h
@@ -702,6 +702,8 @@ int new_socket_id(unsigned int socket_id);
 
 queueid_t get_allowed_max_nb_rxq(portid_t *pid);
 int check_nb_rxq(queueid_t rxq);
+queueid_t get_allowed_max_nb_txq(portid_t *pid);
+int check_nb_txq(queueid_t txq);
 
 /*
  * Work-around of a compilation error with ICC on invocations of the
-- 
2.7.5