Re: [dpdk-dev] [PATCH v2] examples/client_server_mp: check port ownership

[Matan Azrad <matan@mellanox.com>]

Hi Stephen

From: Stephen Hemminger
> From: Stephen Hemminger <sthemmin@microsoft.com>
> 
> The mp_server would accept a port mask that included hidden (owned)
> ports and which later caused either lost packets or failed initialization.
> 
> This fixes explicitly checks for ownership when parsing the port mask.
> 
> Fixes: 5b7ba31148a8 ("ethdev: add port ownership")
> Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
> ---
> v2 - fix checkpatch complains about return and else
> 
>  .../client_server_mp/mp_server/args.c         | 35 +++++++++++++------
>  1 file changed, 24 insertions(+), 11 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..72cb85008c39 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"
> @@ -45,27 +46,39 @@ parse_portmask(uint8_t max_ports, 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) {
> +		struct rte_eth_dev_owner owner;
> +
> +		if ((pm & 0x1) == 0)
> +			continue;
> +
> +		if (count >= max_ports) {
> +			printf("WARNING: requested port %u not present -
> ignoring\n",
> +				count);
> +			continue;
> +		}
> +		if (rte_eth_dev_owner_get(count, &owner) < 0) {
> +			printf("ERROR: can not find port %u owner\n",
> count);

What if some entity will take ownership later?
If you want the app will be ownership aware:
	if you sure that you want this port to be owned by this application you need to take ownership on it.
else:
the port is hidden by RTE_ETH_FOREACH_DEV if it is owned by some entity. 
see how it was done in testpmd function: port_id_is_invalid().


> +			return -1;
>  		}
> -		pm = (pm >> 1);
> -		count++;
> +		if (owner.id != RTE_ETH_DEV_NO_OWNER) {
> +			printf("ERROR: requested port %u is owned by
> device %s\n",
> +					count, owner.name);
> +			return -1;
> +		}
> +
> +		ports->id[ports->num_ports++] = count;
>  	}
> 
>  	return 0;
> --