diff mbox series

[v4,1/4] examples/multi_process/client_server_mp: check port validity

Message ID 20190726165054.24078-2-stephen@networkplumber.org (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series examples/client_server_mp: fix port issues |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/Intel-compilation success Compilation OK
ci/iol-Compile-Testing success Compile Testing PASS

Commit Message

Stephen Hemminger July 26, 2019, 4:50 p.m. UTC 
  From: Stephen Hemminger <sthemmin@microsoft.com>

The mp_server incorrectly allows a port mask that included hidden
ports and which later caused either lost packets or failed initialization.

This fixes explicitly checking that each bit in portmask is a
valid port before using it.

Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
---
 .../client_server_mp/mp_server/args.c         | 46 +++++++++++++------
 .../client_server_mp/mp_server/args.h         |  2 +-
 .../client_server_mp/mp_server/init.c         |  7 +--
 3 files changed, 35 insertions(+), 20 deletions(-)

Comments

Matan Azrad July 30, 2019, 9:21 a.m. UTC | #1 
Hi Stephen

From:  Stephen Hemminger
> From: Stephen Hemminger <sthemmin@microsoft.com>
> 
> The mp_server incorrectly allows a port mask that included hidden ports and
> which later caused either lost packets or failed initialization.
> 
> This fixes explicitly checking that each bit in portmask is a valid port before
> using it.
> 
> Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
> Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
> ---
>  .../client_server_mp/mp_server/args.c         | 46 +++++++++++++------
>  .../client_server_mp/mp_server/args.h         |  2 +-
>  .../client_server_mp/mp_server/init.c         |  7 +--
>  3 files changed, 35 insertions(+), 20 deletions(-)
> 
> diff --git a/examples/multi_process/client_server_mp/mp_server/args.c
> b/examples/multi_process/client_server_mp/mp_server/args.c
> index b0d8d7665c85..c1ab12ad00d1 100644
> --- a/examples/multi_process/client_server_mp/mp_server/args.c
> +++ b/examples/multi_process/client_server_mp/mp_server/args.c
> @@ -10,6 +10,7 @@
>  #include <errno.h>
> 
>  #include <rte_memory.h>
> +#include <rte_ethdev.h>
>  #include <rte_string_fns.h>
> 
>  #include "common.h"
> @@ -34,6 +35,22 @@ usage(void)
>  	    , progname);
>  }
> 
> +/**
> + * Check if port is present in the system
> + * It maybe owned by a device and should not be used.
> + */
> +static int
> +port_is_present(uint16_t portid)
> +{
> +	uint16_t id;
> +
> +	RTE_ETH_FOREACH_DEV(id) {
> +		if (id == portid)
> +			return 1;
> +	}
> +	return 0;
> +}
> +
>  /**
>   * The ports to be used by the application are passed in
>   * the form of a bitmask. This function parses the bitmask @@ -41,31 +58,32
> @@ usage(void)
>   * array variable
>   */
>  static int
> -parse_portmask(uint8_t max_ports, const char *portmask)
> +parse_portmask(const char *portmask)
>  {
>  	char *end = NULL;
>  	unsigned long pm;
> -	uint16_t count = 0;
> +	uint16_t count;
> 
>  	if (portmask == NULL || *portmask == '\0')
>  		return -1;
> 
>  	/* convert parameter to a number and verify */
>  	pm = strtoul(portmask, &end, 16);
> -	if (end == NULL || *end != '\0' || pm == 0)
> +	if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
>  		return -1;
> 
>  	/* loop through bits of the mask and mark ports */
> -	while (pm != 0){
> -		if (pm & 0x01){ /* bit is set in mask, use port */
> -			if (count >= max_ports)
> -				printf("WARNING: requested port %u not
> present"
> -				" - ignoring\n", (unsigned)count);
> -			else
> -			    ports->id[ports->num_ports++] = count;
> +	for (count = 0; pm != 0; pm >>= 1, ++count) {
> +		if ((pm & 0x1) == 0)
> +			continue;
> +
> +		if (!port_is_present(count)) {
> +			printf("WARNING: requested port %u not present -
> ignoring\n",
> +				count);
> +			continue;
>  		}
> -		pm = (pm >> 1);
> -		count++;
> +
> +		ports->id[ports->num_ports++] = count;
>  	}

Why not just to do something like:

RTE_ETH_FOREACH_DEV(id) {
	If (pm & (1 << id)) {
		pm &= ~(1 << id) 
		put in list
	}
}
	If (pm) 
		Warning



>  	return 0;
> @@ -99,7 +117,7 @@ parse_num_clients(const char *clients)
>   * on error.
>   */
>  int
> -parse_app_args(uint16_t max_ports, int argc, char *argv[])
> +parse_app_args(int argc, char *argv[])
>  {
>  	int option_index, opt;
>  	char **argvopt = argv;
> @@ -112,7 +130,7 @@ parse_app_args(uint16_t max_ports, int argc, char
> *argv[])
>  		&option_index)) != EOF){
>  		switch (opt){
>  			case 'p':
> -				if (parse_portmask(max_ports, optarg) != 0){
> +				if (parse_portmask(optarg) != 0) {
>  					usage();
>  					return -1;
>  				}
> diff --git a/examples/multi_process/client_server_mp/mp_server/args.h
> b/examples/multi_process/client_server_mp/mp_server/args.h
> index 79c190a33a37..52c8cc86e6f0 100644
> --- a/examples/multi_process/client_server_mp/mp_server/args.h
> +++ b/examples/multi_process/client_server_mp/mp_server/args.h
> @@ -5,6 +5,6 @@
>  #ifndef _ARGS_H_
>  #define _ARGS_H_
> 
> -int parse_app_args(uint16_t max_ports, int argc, char *argv[]);
> +int parse_app_args(int argc, char *argv[]);
> 
>  #endif /* ifndef _ARGS_H_ */
> diff --git a/examples/multi_process/client_server_mp/mp_server/init.c
> b/examples/multi_process/client_server_mp/mp_server/init.c
> index 3af5dc6994bf..1b0569937b51 100644
> --- a/examples/multi_process/client_server_mp/mp_server/init.c
> +++ b/examples/multi_process/client_server_mp/mp_server/init.c
> @@ -238,7 +238,7 @@ init(int argc, char *argv[])  {
>  	int retval;
>  	const struct rte_memzone *mz;
> -	uint16_t i, total_ports;
> +	uint16_t i;
> 
>  	/* init EAL, parsing EAL args */
>  	retval = rte_eal_init(argc, argv);
> @@ -247,9 +247,6 @@ init(int argc, char *argv[])
>  	argc -= retval;
>  	argv += retval;
> 
> -	/* get total number of ports */
> -	total_ports = rte_eth_dev_count_total();
> -
>  	/* set up array for port data */
>  	mz = rte_memzone_reserve(MZ_PORT_INFO, sizeof(*ports),
>  				rte_socket_id(), NO_FLAGS);
> @@ -259,7 +256,7 @@ init(int argc, char *argv[])
>  	ports = mz->addr;
> 
>  	/* parse additional, application arguments */
> -	retval = parse_app_args(total_ports, argc, argv);
> +	retval = parse_app_args(argc, argv);
>  	if (retval != 0)
>  		return -1;
> 
> --
> 2.20.1
Stephen Hemminger July 30, 2019, 3:56 p.m. UTC | #2 
On Tue, 30 Jul 2019 09:21:02 +0000
Matan Azrad <matan@mellanox.com> wrote:

> Hi Stephen
> 
> From:  Stephen Hemminger
> > From: Stephen Hemminger <sthemmin@microsoft.com>
> > 
> > The mp_server incorrectly allows a port mask that included hidden ports and
> > which later caused either lost packets or failed initialization.
> > 
> > This fixes explicitly checking that each bit in portmask is a valid port before
> > using it.
> > 
> > Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
> > Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
> > ---
> >  .../client_server_mp/mp_server/args.c         | 46 +++++++++++++------
> >  .../client_server_mp/mp_server/args.h         |  2 +-
> >  .../client_server_mp/mp_server/init.c         |  7 +--
> >  3 files changed, 35 insertions(+), 20 deletions(-)
> > 
> > diff --git a/examples/multi_process/client_server_mp/mp_server/args.c
> > b/examples/multi_process/client_server_mp/mp_server/args.c
> > index b0d8d7665c85..c1ab12ad00d1 100644
> > --- a/examples/multi_process/client_server_mp/mp_server/args.c
> > +++ b/examples/multi_process/client_server_mp/mp_server/args.c
> > @@ -10,6 +10,7 @@
> >  #include <errno.h>
> > 
> >  #include <rte_memory.h>
> > +#include <rte_ethdev.h>
> >  #include <rte_string_fns.h>
> > 
> >  #include "common.h"
> > @@ -34,6 +35,22 @@ usage(void)
> >  	    , progname);
> >  }
> > 
> > +/**
> > + * Check if port is present in the system
> > + * It maybe owned by a device and should not be used.
> > + */
> > +static int
> > +port_is_present(uint16_t portid)
> > +{
> > +	uint16_t id;
> > +
> > +	RTE_ETH_FOREACH_DEV(id) {
> > +		if (id == portid)
> > +			return 1;
> > +	}
> > +	return 0;
> > +}
> > +
> >  /**
> >   * The ports to be used by the application are passed in
> >   * the form of a bitmask. This function parses the bitmask @@ -41,31 +58,32
> > @@ usage(void)
> >   * array variable
> >   */
> >  static int
> > -parse_portmask(uint8_t max_ports, const char *portmask)
> > +parse_portmask(const char *portmask)
> >  {
> >  	char *end = NULL;
> >  	unsigned long pm;
> > -	uint16_t count = 0;
> > +	uint16_t count;
> > 
> >  	if (portmask == NULL || *portmask == '\0')
> >  		return -1;
> > 
> >  	/* convert parameter to a number and verify */
> >  	pm = strtoul(portmask, &end, 16);
> > -	if (end == NULL || *end != '\0' || pm == 0)
> > +	if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
> >  		return -1;
> > 
> >  	/* loop through bits of the mask and mark ports */
> > -	while (pm != 0){
> > -		if (pm & 0x01){ /* bit is set in mask, use port */
> > -			if (count >= max_ports)
> > -				printf("WARNING: requested port %u not
> > present"
> > -				" - ignoring\n", (unsigned)count);
> > -			else
> > -			    ports->id[ports->num_ports++] = count;
> > +	for (count = 0; pm != 0; pm >>= 1, ++count) {
> > +		if ((pm & 0x1) == 0)
> > +			continue;
> > +
> > +		if (!port_is_present(count)) {
> > +			printf("WARNING: requested port %u not present -
> > ignoring\n",
> > +				count);
> > +			continue;
> >  		}
> > -		pm = (pm >> 1);
> > -		count++;
> > +
> > +		ports->id[ports->num_ports++] = count;
> >  	}  
> 
> Why not just to do something like:
> 
> RTE_ETH_FOREACH_DEV(id) {
> 	If (pm & (1 << id)) {
> 		pm &= ~(1 << id) 
> 		put in list
> 	}
> }
> 	If (pm) 
> 		Warning
> 

No real reason, was just trying to keep existing logic flow
Matan Azrad July 30, 2019, 4:39 p.m. UTC | #3 
Hi

From: Stephen Hemminger
> On Tue, 30 Jul 2019 09:21:02 +0000
> Matan Azrad <matan@mellanox.com> wrote:
> 
> > Hi Stephen
> >
> > From:  Stephen Hemminger
> > > From: Stephen Hemminger <sthemmin@microsoft.com>
> > >
> > > The mp_server incorrectly allows a port mask that included hidden
> > > ports and which later caused either lost packets or failed initialization.
> > >
> > > This fixes explicitly checking that each bit in portmask is a valid
> > > port before using it.
> > >
> > > Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
> > > Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
> > > ---
> > >  .../client_server_mp/mp_server/args.c         | 46 +++++++++++++------
> > >  .../client_server_mp/mp_server/args.h         |  2 +-
> > >  .../client_server_mp/mp_server/init.c         |  7 +--
> > >  3 files changed, 35 insertions(+), 20 deletions(-)
> > >
> > > diff --git
> > > a/examples/multi_process/client_server_mp/mp_server/args.c
> > > b/examples/multi_process/client_server_mp/mp_server/args.c
> > > index b0d8d7665c85..c1ab12ad00d1 100644
> > > --- a/examples/multi_process/client_server_mp/mp_server/args.c
> > > +++ b/examples/multi_process/client_server_mp/mp_server/args.c
> > > @@ -10,6 +10,7 @@
> > >  #include <errno.h>
> > >
> > >  #include <rte_memory.h>
> > > +#include <rte_ethdev.h>
> > >  #include <rte_string_fns.h>
> > >
> > >  #include "common.h"
> > > @@ -34,6 +35,22 @@ usage(void)
> > >  	    , progname);
> > >  }
> > >
> > > +/**
> > > + * Check if port is present in the system
> > > + * It maybe owned by a device and should not be used.
> > > + */
> > > +static int
> > > +port_is_present(uint16_t portid)
> > > +{
> > > +	uint16_t id;
> > > +
> > > +	RTE_ETH_FOREACH_DEV(id) {
> > > +		if (id == portid)
> > > +			return 1;
> > > +	}
> > > +	return 0;
> > > +}
> > > +
> > >  /**
> > >   * The ports to be used by the application are passed in
> > >   * the form of a bitmask. This function parses the bitmask @@
> > > -41,31 +58,32 @@ usage(void)
> > >   * array variable
> > >   */
> > >  static int
> > > -parse_portmask(uint8_t max_ports, const char *portmask)
> > > +parse_portmask(const char *portmask)
> > >  {
> > >  	char *end = NULL;
> > >  	unsigned long pm;
> > > -	uint16_t count = 0;
> > > +	uint16_t count;
> > >
> > >  	if (portmask == NULL || *portmask == '\0')
> > >  		return -1;
> > >
> > >  	/* convert parameter to a number and verify */
> > >  	pm = strtoul(portmask, &end, 16);
> > > -	if (end == NULL || *end != '\0' || pm == 0)
> > > +	if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
> > >  		return -1;
> > >
> > >  	/* loop through bits of the mask and mark ports */
> > > -	while (pm != 0){
> > > -		if (pm & 0x01){ /* bit is set in mask, use port */
> > > -			if (count >= max_ports)
> > > -				printf("WARNING: requested port %u not
> > > present"
> > > -				" - ignoring\n", (unsigned)count);
> > > -			else
> > > -			    ports->id[ports->num_ports++] = count;
> > > +	for (count = 0; pm != 0; pm >>= 1, ++count) {
> > > +		if ((pm & 0x1) == 0)
> > > +			continue;
> > > +
> > > +		if (!port_is_present(count)) {
> > > +			printf("WARNING: requested port %u not present -
> > > ignoring\n",
> > > +				count);
> > > +			continue;
> > >  		}
> > > -		pm = (pm >> 1);
> > > -		count++;
> > > +
> > > +		ports->id[ports->num_ports++] = count;
> > >  	}
> >
> > Why not just to do something like:
> >
> > RTE_ETH_FOREACH_DEV(id) {
> > 	If (pm & (1 << id)) {
> > 		pm &= ~(1 << id)
> > 		put in list
> > 	}
> > }
> > 	If (pm)
> > 		Warning
> >
> 
> No real reason, was just trying to keep existing logic flow

This is an example for the users\developers, and you on it,
I think this is a good chance to show how to do it in the correct way - O(n) instead O(n^2).

Don't you think so?
 
I suggest to adjust.
Stephen Hemminger July 30, 2019, 4:50 p.m. UTC | #4 
On Tue, 30 Jul 2019 16:39:52 +0000
Matan Azrad <matan@mellanox.com> wrote:

> Hi
> 
> From: Stephen Hemminger
> > On Tue, 30 Jul 2019 09:21:02 +0000
> > Matan Azrad <matan@mellanox.com> wrote:
> >   
> > > Hi Stephen
> > >
> > > From:  Stephen Hemminger  
> > > > From: Stephen Hemminger <sthemmin@microsoft.com>
> > > >
> > > > The mp_server incorrectly allows a port mask that included hidden
> > > > ports and which later caused either lost packets or failed initialization.
> > > >
> > > > This fixes explicitly checking that each bit in portmask is a valid
> > > > port before using it.
> > > >
> > > > Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
> > > > Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
> > > > ---
> > > >  .../client_server_mp/mp_server/args.c         | 46 +++++++++++++------
> > > >  .../client_server_mp/mp_server/args.h         |  2 +-
> > > >  .../client_server_mp/mp_server/init.c         |  7 +--
> > > >  3 files changed, 35 insertions(+), 20 deletions(-)
> > > >
> > > > diff --git
> > > > a/examples/multi_process/client_server_mp/mp_server/args.c
> > > > b/examples/multi_process/client_server_mp/mp_server/args.c
> > > > index b0d8d7665c85..c1ab12ad00d1 100644
> > > > --- a/examples/multi_process/client_server_mp/mp_server/args.c
> > > > +++ b/examples/multi_process/client_server_mp/mp_server/args.c
> > > > @@ -10,6 +10,7 @@
> > > >  #include <errno.h>
> > > >
> > > >  #include <rte_memory.h>
> > > > +#include <rte_ethdev.h>
> > > >  #include <rte_string_fns.h>
> > > >
> > > >  #include "common.h"
> > > > @@ -34,6 +35,22 @@ usage(void)
> > > >  	    , progname);
> > > >  }
> > > >
> > > > +/**
> > > > + * Check if port is present in the system
> > > > + * It maybe owned by a device and should not be used.
> > > > + */
> > > > +static int
> > > > +port_is_present(uint16_t portid)
> > > > +{
> > > > +	uint16_t id;
> > > > +
> > > > +	RTE_ETH_FOREACH_DEV(id) {
> > > > +		if (id == portid)
> > > > +			return 1;
> > > > +	}
> > > > +	return 0;
> > > > +}
> > > > +
> > > >  /**
> > > >   * The ports to be used by the application are passed in
> > > >   * the form of a bitmask. This function parses the bitmask @@
> > > > -41,31 +58,32 @@ usage(void)
> > > >   * array variable
> > > >   */
> > > >  static int
> > > > -parse_portmask(uint8_t max_ports, const char *portmask)
> > > > +parse_portmask(const char *portmask)
> > > >  {
> > > >  	char *end = NULL;
> > > >  	unsigned long pm;
> > > > -	uint16_t count = 0;
> > > > +	uint16_t count;
> > > >
> > > >  	if (portmask == NULL || *portmask == '\0')
> > > >  		return -1;
> > > >
> > > >  	/* convert parameter to a number and verify */
> > > >  	pm = strtoul(portmask, &end, 16);
> > > > -	if (end == NULL || *end != '\0' || pm == 0)
> > > > +	if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
> > > >  		return -1;
> > > >
> > > >  	/* loop through bits of the mask and mark ports */
> > > > -	while (pm != 0){
> > > > -		if (pm & 0x01){ /* bit is set in mask, use port */
> > > > -			if (count >= max_ports)
> > > > -				printf("WARNING: requested port %u not
> > > > present"
> > > > -				" - ignoring\n", (unsigned)count);
> > > > -			else
> > > > -			    ports->id[ports->num_ports++] = count;
> > > > +	for (count = 0; pm != 0; pm >>= 1, ++count) {
> > > > +		if ((pm & 0x1) == 0)
> > > > +			continue;
> > > > +
> > > > +		if (!port_is_present(count)) {
> > > > +			printf("WARNING: requested port %u not present -
> > > > ignoring\n",
> > > > +				count);
> > > > +			continue;
> > > >  		}
> > > > -		pm = (pm >> 1);
> > > > -		count++;
> > > > +
> > > > +		ports->id[ports->num_ports++] = count;
> > > >  	}  
> > >
> > > Why not just to do something like:
> > >
> > > RTE_ETH_FOREACH_DEV(id) {
> > > 	If (pm & (1 << id)) {
> > > 		pm &= ~(1 << id)
> > > 		put in list
> > > 	}
> > > }
> > > 	If (pm)
> > > 		Warning
> > >  
> > 
> > No real reason, was just trying to keep existing logic flow  
> 
> This is an example for the users\developers, and you on it,
> I think this is a good chance to show how to do it in the correct way - O(n) instead O(n^2).
> 
> Don't you think so?
>  
> I suggest to adjust. 
> 

This is a toy example short loops, it doesn't matter.
It is important to catch case where portmask contains hidden ports.
diff mbox series

Patch

diff --git a/examples/multi_process/client_server_mp/mp_server/args.c b/examples/multi_process/client_server_mp/mp_server/args.c
index b0d8d7665c85..c1ab12ad00d1 100644
--- a/examples/multi_process/client_server_mp/mp_server/args.c
+++ b/examples/multi_process/client_server_mp/mp_server/args.c
@@ -10,6 +10,7 @@ 
 #include <errno.h>
 
 #include <rte_memory.h>
+#include <rte_ethdev.h>
 #include <rte_string_fns.h>
 
 #include "common.h"
@@ -34,6 +35,22 @@  usage(void)
 	    , progname);
 }
 
+/**
+ * Check if port is present in the system
+ * It maybe owned by a device and should not be used.
+ */
+static int
+port_is_present(uint16_t portid)
+{
+	uint16_t id;
+
+	RTE_ETH_FOREACH_DEV(id) {
+		if (id == portid)
+			return 1;
+	}
+	return 0;
+}
+
 /**
  * The ports to be used by the application are passed in
  * the form of a bitmask. This function parses the bitmask
@@ -41,31 +58,32 @@  usage(void)
  * array variable
  */
 static int
-parse_portmask(uint8_t max_ports, const char *portmask)
+parse_portmask(const char *portmask)
 {
 	char *end = NULL;
 	unsigned long pm;
-	uint16_t count = 0;
+	uint16_t count;
 
 	if (portmask == NULL || *portmask == '\0')
 		return -1;
 
 	/* convert parameter to a number and verify */
 	pm = strtoul(portmask, &end, 16);
-	if (end == NULL || *end != '\0' || pm == 0)
+	if (end == NULL || *end != '\0' || pm > UINT16_MAX || pm == 0)
 		return -1;
 
 	/* loop through bits of the mask and mark ports */
-	while (pm != 0){
-		if (pm & 0x01){ /* bit is set in mask, use port */
-			if (count >= max_ports)
-				printf("WARNING: requested port %u not present"
-				" - ignoring\n", (unsigned)count);
-			else
-			    ports->id[ports->num_ports++] = count;
+	for (count = 0; pm != 0; pm >>= 1, ++count) {
+		if ((pm & 0x1) == 0)
+			continue;
+
+		if (!port_is_present(count)) {
+			printf("WARNING: requested port %u not present - ignoring\n",
+				count);
+			continue;
 		}
-		pm = (pm >> 1);
-		count++;
+
+		ports->id[ports->num_ports++] = count;
 	}
 
 	return 0;
@@ -99,7 +117,7 @@  parse_num_clients(const char *clients)
  * on error.
  */
 int
-parse_app_args(uint16_t max_ports, int argc, char *argv[])
+parse_app_args(int argc, char *argv[])
 {
 	int option_index, opt;
 	char **argvopt = argv;
@@ -112,7 +130,7 @@  parse_app_args(uint16_t max_ports, int argc, char *argv[])
 		&option_index)) != EOF){
 		switch (opt){
 			case 'p':
-				if (parse_portmask(max_ports, optarg) != 0){
+				if (parse_portmask(optarg) != 0) {
 					usage();
 					return -1;
 				}
diff --git a/examples/multi_process/client_server_mp/mp_server/args.h b/examples/multi_process/client_server_mp/mp_server/args.h
index 79c190a33a37..52c8cc86e6f0 100644
--- a/examples/multi_process/client_server_mp/mp_server/args.h
+++ b/examples/multi_process/client_server_mp/mp_server/args.h
@@ -5,6 +5,6 @@ 
 #ifndef _ARGS_H_
 #define _ARGS_H_
 
-int parse_app_args(uint16_t max_ports, int argc, char *argv[]);
+int parse_app_args(int argc, char *argv[]);
 
 #endif /* ifndef _ARGS_H_ */
diff --git a/examples/multi_process/client_server_mp/mp_server/init.c b/examples/multi_process/client_server_mp/mp_server/init.c
index 3af5dc6994bf..1b0569937b51 100644
--- a/examples/multi_process/client_server_mp/mp_server/init.c
+++ b/examples/multi_process/client_server_mp/mp_server/init.c
@@ -238,7 +238,7 @@  init(int argc, char *argv[])
 {
 	int retval;
 	const struct rte_memzone *mz;
-	uint16_t i, total_ports;
+	uint16_t i;
 
 	/* init EAL, parsing EAL args */
 	retval = rte_eal_init(argc, argv);
@@ -247,9 +247,6 @@  init(int argc, char *argv[])
 	argc -= retval;
 	argv += retval;
 
-	/* get total number of ports */
-	total_ports = rte_eth_dev_count_total();
-
 	/* set up array for port data */
 	mz = rte_memzone_reserve(MZ_PORT_INFO, sizeof(*ports),
 				rte_socket_id(), NO_FLAGS);
@@ -259,7 +256,7 @@  init(int argc, char *argv[])
 	ports = mz->addr;
 
 	/* parse additional, application arguments */
-	retval = parse_app_args(total_ports, argc, argv);
+	retval = parse_app_args(argc, argv);
 	if (retval != 0)
 		return -1;