Hi Xuan,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on bpf-next/master]

url:    https://github.com/0day-ci/linux/commits/Xuan-Zhuo/xsk-build-skb-by-page/20210116-105116
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
config: sh-allmodconfig (attached as .config)
compiler: sh4-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/ee139d2988e5c5945108889a7c95c751910c1877
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Xuan-Zhuo/xsk-build-skb-by-page/20210116-105116
        git checkout ee139d2988e5c5945108889a7c95c751910c1877
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   net/xdp/xsk.c: In function 'xsk_build_skb':
>> net/xdp/xsk.c:497:4: error: invalid type argument of unary '*' (have 'int')
     497 |    *err = -ENOMEM;
         |    ^~~~
   net/xdp/xsk.c:508:4: error: invalid type argument of unary '*' (have 'int')
     508 |    *err = -EINVAL;
         |    ^~~~
   net/xdp/xsk.c:490:7: warning: variable 'addr' set but not used [-Wunused-but-set-variable]
     490 |   u64 addr;
         |       ^~~~

Kconfig warnings: (for reference only)
   WARNING: unmet direct dependencies detected for SND_ATMEL_SOC_PDC
   Depends on SOUND && !UML && SND && SND_SOC && SND_ATMEL_SOC && HAS_DMA
   Selected by
   - SND_ATMEL_SOC_SSC && SOUND && !UML && SND && SND_SOC && SND_ATMEL_SOC
   - SND_ATMEL_SOC_SSC_PDC && SOUND && !UML && SND && SND_SOC && SND_ATMEL_SOC && ATMEL_SSC


vim +497 net/xdp/xsk.c

   476	
   477	static struct sk_buff *xsk_build_skb(struct xdp_sock *xs,
   478					     struct xdp_desc *desc, int *err)
   479	{
   480		struct sk_buff *skb;
   481	
   482		if (xs->dev->features & NETIF_F_SKB_NO_LINEAR) {
   483			skb = xsk_build_skb_zerocopy(xs, desc);
   484			if (unlikely(!skb)) {
   485				*err = -ENOMEM;
   486				return NULL;
   487			}
   488		} else {
   489			char *buffer;
   490			u64 addr;
   491			u32 len;
   492			int err;
   493	
   494			len = desc->len;
   495			skb = sock_alloc_send_skb(&xs->sk, len, 1, &err);
   496			if (unlikely(!skb)) {
 > 497				*err = -ENOMEM;
   498				return NULL;
   499			}
   500	
   501			skb_put(skb, len);
   502			addr = desc->addr;
   503			buffer = xsk_buff_raw_get_data(xs->pool, desc->addr);
   504			err = skb_store_bits(skb, 0, buffer, len);
   505	
   506			if (unlikely(err)) {
   507				kfree_skb(skb);
   508				*err = -EINVAL;
   509				return NULL;
   510			}
   511		}
   512	
   513		skb->dev = xs->dev;
   514		skb->priority = xs->sk.sk_priority;
   515		skb->mark = xs->sk.sk_mark;
   516		skb_shinfo(skb)->destructor_arg = (void *)(long)desc->addr;
   517		skb->destructor = xsk_destruct_skb;
   518	
   519		return skb;
   520	}
   521	

---
0-DAY CI Kernel Test Service, Intel Corporation
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