Hi Daniel,

kernel test robot noticed the following build warnings:

[auto build test WARNING on net-next/main]

url:    https://github.com/intel-lab-lkp/linux/commits/Daniel-Jurgens/virtio-pci-Expose-generic-device-capability-operations/20250909-005006
base:   net-next/main
patch link:    https://lore.kernel.org/r/20250908164046.25051-4-danielj%40nvidia.com
patch subject: [PATCH net-next v2 03/11] virtio_net: Create virtio_net directory
config: sparc-randconfig-002-20250910 (https://download.01.org/0day-ci/archive/20250910/202509100236.iFI48Aer-lkp@intel.com/config)
compiler: sparc64-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250910/202509100236.iFI48Aer-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot [off-list ref]
| Closes: https://lore.kernel.org/oe-kbuild-all/202509100236.iFI48Aer-lkp@intel.com/ (local)

All warnings (new ones prefixed by >>):

   drivers/net/virtio_net/virtio_net_main.c: In function 'virtnet_probe':

quoted

drivers/net/virtio_net/virtio_net_main.c:6487:36: warning: 'sprintf' may write a terminating nul past the end of the destination [-Wformat-overflow=]

      sprintf(vi->rq[i].name, "input.%u", i);
                                       ^
   drivers/net/virtio_net/virtio_net_main.c:6487:3: note: 'sprintf' output between 8 and 17 bytes into a destination of size 16
      sprintf(vi->rq[i].name, "input.%u", i);
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

quoted

drivers/net/virtio_net/virtio_net_main.c:6488:35: warning: '%u' directive writing between 1 and 10 bytes into a region of size 9 [-Wformat-overflow=]

      sprintf(vi->sq[i].name, "output.%u", i);
                                      ^~
   drivers/net/virtio_net/virtio_net_main.c:6488:27: note: directive argument in the range [0, 2147483647]
      sprintf(vi->sq[i].name, "output.%u", i);
                              ^~~~~~~~~~~
   drivers/net/virtio_net/virtio_net_main.c:6488:3: note: 'sprintf' output between 9 and 18 bytes into a destination of size 16
      sprintf(vi->sq[i].name, "output.%u", i);
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


vim +/sprintf +6487 drivers/net/virtio_net/virtio_net_main.c

d85b758f72b05a drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-09  6446  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6447  static int virtnet_find_vqs(struct virtnet_info *vi)
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6448  {
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6449  	struct virtqueue_info *vqs_info;
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6450  	struct virtqueue **vqs;
e3fe8d28c67bf6 drivers/net/virtio_net.c Zhu Yanjun         2024-01-04  6451  	int ret = -ENOMEM;
e3fe8d28c67bf6 drivers/net/virtio_net.c Zhu Yanjun         2024-01-04  6452  	int total_vqs;
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6453  	bool *ctx;
e3fe8d28c67bf6 drivers/net/virtio_net.c Zhu Yanjun         2024-01-04  6454  	u16 i;
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6455  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6456  	/* We expect 1 RX virtqueue followed by 1 TX virtqueue, followed by
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6457  	 * possible N-1 RX/TX queue pairs used in multiqueue mode, followed by
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6458  	 * possible control vq.
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6459  	 */
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6460  	total_vqs = vi->max_queue_pairs * 2 +
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6461  		    virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VQ);
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6462  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6463  	/* Allocate space for find_vqs parameters */
6396bb221514d2 drivers/net/virtio_net.c Kees Cook          2018-06-12  6464  	vqs = kcalloc(total_vqs, sizeof(*vqs), GFP_KERNEL);
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6465  	if (!vqs)
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6466  		goto err_vq;
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6467  	vqs_info = kcalloc(total_vqs, sizeof(*vqs_info), GFP_KERNEL);
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6468  	if (!vqs_info)
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6469  		goto err_vqs_info;
192f68cf35f5ee drivers/net/virtio_net.c Jason Wang         2017-07-19  6470  	if (!vi->big_packets || vi->mergeable_rx_bufs) {
6396bb221514d2 drivers/net/virtio_net.c Kees Cook          2018-06-12  6471  		ctx = kcalloc(total_vqs, sizeof(*ctx), GFP_KERNEL);
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6472  		if (!ctx)
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6473  			goto err_ctx;
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6474  	} else {
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6475  		ctx = NULL;
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6476  	}
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6477  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6478  	/* Parameters for control virtqueue, if any */
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6479  	if (vi->has_cvq) {
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6480  		vqs_info[total_vqs - 1].name = "control";
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6481  	}
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6482  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6483  	/* Allocate/initialize parameters for send/receive virtqueues */
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6484  	for (i = 0; i < vi->max_queue_pairs; i++) {
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6485  		vqs_info[rxq2vq(i)].callback = skb_recv_done;
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6486  		vqs_info[txq2vq(i)].callback = skb_xmit_done;
e3fe8d28c67bf6 drivers/net/virtio_net.c Zhu Yanjun         2024-01-04 @6487  		sprintf(vi->rq[i].name, "input.%u", i);
e3fe8d28c67bf6 drivers/net/virtio_net.c Zhu Yanjun         2024-01-04 @6488  		sprintf(vi->sq[i].name, "output.%u", i);
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6489  		vqs_info[rxq2vq(i)].name = vi->rq[i].name;
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6490  		vqs_info[txq2vq(i)].name = vi->sq[i].name;
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6491  		if (ctx)
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6492  			vqs_info[rxq2vq(i)].ctx = true;
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6493  	}
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6494  
6c85d6b653caeb drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6495  	ret = virtio_find_vqs(vi->vdev, total_vqs, vqs, vqs_info, NULL);
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6496  	if (ret)
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6497  		goto err_find;
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6498  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6499  	if (vi->has_cvq) {
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6500  		vi->cvq = vqs[total_vqs - 1];
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6501  		if (virtio_has_feature(vi->vdev, VIRTIO_NET_F_CTRL_VLAN))
f646968f8f7c62 drivers/net/virtio_net.c Patrick McHardy    2013-04-19  6502  			vi->dev->features |= NETIF_F_HW_VLAN_CTAG_FILTER;
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6503  	}
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6504  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6505  	for (i = 0; i < vi->max_queue_pairs; i++) {
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6506  		vi->rq[i].vq = vqs[rxq2vq(i)];
d85b758f72b05a drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-09  6507  		vi->rq[i].min_buf_len = mergeable_min_buf_len(vi, vi->rq[i].vq);
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6508  		vi->sq[i].vq = vqs[txq2vq(i)];
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6509  	}
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6510  
2fa3c8a8b23041 drivers/net/virtio_net.c Tonghao Zhang      2018-05-31  6511  	/* run here: ret == 0. */
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6512  
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6513  
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6514  err_find:
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6515  	kfree(ctx);
d45b897b11eaf9 drivers/net/virtio_net.c Michael S. Tsirkin 2017-03-06  6516  err_ctx:
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6517  	kfree(vqs_info);
c2c6325e1645b5 drivers/net/virtio_net.c Jiri Pirko         2024-07-08  6518  err_vqs_info:
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6519  	kfree(vqs);
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6520  err_vq:
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6521  	return ret;
3f9c10b0d478a3 drivers/net/virtio_net.c Amit Shah          2011-12-22  6522  }
986a4f4d452dec drivers/net/virtio_net.c Jason Wang         2012-12-07  6523  

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki