tree: https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git queue-4.14 head: baa67d3d69c44ce8c5d720cb707244cb006dc253 commit: baa67d3d69c44ce8c5d720cb707244cb006dc253 [1/1] virtio_net: Do not pull payload in skb->head config: x86_64-randconfig-a014-20210411 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 00ef28ef21f0a46059203c5aa96e9febe1192e43) 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 # install x86_64 cross compiling tool for clang build # apt-get install binutils-x86-64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git/c... git remote add sashal-linux-stable https://git.kernel.org/pub/scm/linux/kernel/git/sashal/linux-stable.git git fetch --no-tags sashal-linux-stable queue-4.14 git checkout baa67d3d69c44ce8c5d720cb707244cb006dc253 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): copy = ETH_HLEN + metasize; ^ 1 error generated. vim +/metasize +348 drivers/net/virtio_net.c 307 308 /* Called from bottom half context */ 309 static struct sk_buff *page_to_skb(struct virtnet_info *vi, 310 struct receive_queue *rq, 311 struct page *page, unsigned int offset, 312 unsigned int len, unsigned int truesize, 313 bool hdr_valid) 314 { 315 struct sk_buff *skb; 316 struct virtio_net_hdr_mrg_rxbuf *hdr; 317 unsigned int copy, hdr_len, hdr_padded_len; 318 char *p; 319 320 p = page_address(page) + offset; 321 322 /* copy small packet so we can reuse these pages for small data */ 323 skb = napi_alloc_skb(&rq->napi, GOOD_COPY_LEN); 324 if (unlikely(!skb)) 325 return NULL; 326 327 hdr = skb_vnet_hdr(skb); 328 329 hdr_len = vi->hdr_len; 330 if (vi->mergeable_rx_bufs) 331 hdr_padded_len = sizeof(*hdr); 332 else 333 hdr_padded_len = sizeof(struct padded_vnet_hdr); 334 335 if (hdr_valid) 336 memcpy(hdr, p, hdr_len); 337 338 len -= hdr_len; 339 offset += hdr_padded_len; 340 p += hdr_padded_len; 341 342 /* Copy all frame if it fits skb->head, otherwise 343 * we let virtio_net_hdr_to_skb() and GRO pull headers as needed. 344 */ 345 if (len <= skb_tailroom(skb)) 346 copy = len; 347 else 349 skb_put_data(skb, p, copy); 350 351 len -= copy; 352 offset += copy; 353 354 if (vi->mergeable_rx_bufs) { 355 if (len) 356 skb_add_rx_frag(skb, 0, page, offset, len, truesize); 357 else 358 put_page(page); 359 return skb; 360 } 361 362 /* 363 * Verify that we can indeed put this data into a skb. 364 * This is here to handle cases when the device erroneously 365 * tries to receive more than is possible. This is usually 366 * the case of a broken device. 367 */ 368 if (unlikely(len > MAX_SKB_FRAGS * PAGE_SIZE)) { 369 net_dbg_ratelimited("%s: too much data\n", skb->dev->name); 370 dev_kfree_skb(skb); 371 return NULL; 372 } 373 BUG_ON(offset >= PAGE_SIZE); 374 while (len) { 375 unsigned int frag_size = min((unsigned)PAGE_SIZE - offset, len); 376 skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, page, offset, 377 frag_size, truesize); 378 len -= frag_size; 379 page = (struct page *)page->private; 380 offset = 0; 381 } 382 383 if (page) 384 give_pages(rq, page); 385 386 return skb; 387 } 388 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org