Subject: Re: [dpdk-dev] [PATCH v2 2/2] net/netvsc: support VF device hot
add/remove

On Mon, 21 Dec 2020 13:33:22 -0800
Long Li [off-list ref] wrote:

quoted

	/* trying to get mac address if this is a network device*/
+		s = socket(PF_INET, SOCK_DGRAM, IPPROTO_IP);
+		if (s == -1) {
+			PMD_DRV_LOG(ERR, "Failed to create socket

errno %d\n",

quoted

+				    errno);
+			break;
+		}
+		strlcpy(req.ifr_name, dir->d_name, sizeof(req.ifr_name));
+		ret = ioctl(s, SIOCGIFHWADDR, &req);
+		close(s);
+		if (ret == -1) {
+			PMD_DRV_LOG(ERR, "Failed to send

SIOCGIFHWADDR for "

quoted

+				    "device %s\n", dir->d_name);
+			break;
+		}
+		if (req.ifr_hwaddr.sa_family != ARPHRD_ETHER) {
+			closedir(di);
+			return;
+		}

You have sysfs directory open at this point, would it be easier to continue
with sysfs to find the mac address?

		snprintf(ifpath, sizeof(ifpath), "%s/address", dir->d_name);
		fd = openat(dirfd(di), ifpath, O_RDONLY);
		read(fd...)

I think sending SIOCGIFHWADDR through socket is safer. This is the same as vdev_netvsc does. If the network hardware is not ethernet, reading the address directly from sysfs may require some additional parsing.