tree: https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git fscache-rewrite-indexing head: 96d4e1af98c26988d3c1b3cf688974c24de90fa9 commit: cf8fa20c911971b0aba604031f1cd488d3a5583b [72/75] 9p: Copy local writes to the cache when writing to the server config: i386-debian-10.3 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/com... git remote add dhowells-fs https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git git fetch --no-tags dhowells-fs fscache-rewrite-indexing git checkout cf8fa20c911971b0aba604031f1cd488d3a5583b # save the attached .config to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash 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 >>): ld: fs/9p/vfs_super.o: in function `fscache_unuse_cookie': include/linux/fscache.h:286: undefined reference to `__fscache_unuse_cookie' ld: include/linux/fscache.h:286: undefined reference to `__fscache_unuse_cookie' ld: fs/9p/vfs_inode.o: in function `fscache_resize_cookie': include/linux/fscache.h:386: undefined reference to `__fscache_resize_cookie' ld: fs/9p/vfs_inode.o: in function `fscache_unuse_cookie': include/linux/fscache.h:286: undefined reference to `__fscache_unuse_cookie' ld: fs/9p/vfs_inode.o: in function `fscache_relinquish_cookie': include/linux/fscache.h:305: undefined reference to `__fscache_relinquish_cookie' ld: fs/9p/vfs_inode.o: in function `fscache_use_cookie': include/linux/fscache.h:269: undefined reference to `__fscache_use_cookie' ld: fs/9p/vfs_inode_dotl.o: in function `fscache_use_cookie': include/linux/fscache.h:269: undefined reference to `__fscache_use_cookie' ld: fs/9p/vfs_addr.o: in function `fscache_write_to_cache': include/linux/fscache.h:596: undefined reference to `__fscache_write_to_cache' ld: fs/9p/vfs_addr.o: in function `fscache_begin_read_operation': include/linux/fscache.h:483: undefined reference to `__fscache_begin_read_operation' ld: fs/9p/vfs_addr.o: in function `v9fs_set_page_dirty': ld: fs/9p/vfs_addr.o: in function `fscache_invalidate': ld: fs/9p/vfs_addr.o: in function `arch_atomic_inc': ld: fs/9p/vfs_file.o: in function `fscache_use_cookie': include/linux/fscache.h:269: undefined reference to `__fscache_use_cookie' ld: fs/9p/vfs_dir.o: in function `fscache_unuse_cookie': include/linux/fscache.h:286: undefined reference to `__fscache_unuse_cookie' ld: include/linux/fscache.h:286: undefined reference to `__fscache_unuse_cookie' ld: fs/9p/v9fs.o: in function `fscache_relinquish_volume': include/linux/fscache.h:221: undefined reference to `__fscache_relinquish_volume' ld: fs/9p/cache.o: in function `fscache_acquire_volume': include/linux/fscache.h:202: undefined reference to `__fscache_acquire_volume' ld: fs/9p/cache.o: in function `fscache_acquire_cookie': include/linux/fscache.h:250: undefined reference to `__fscache_acquire_cookie' vim +365 fs/9p/vfs_addr.c 355 356 #ifdef CONFIG_9P_FSCACHE 357 /* 358 * Mark a page as having been made dirty and thus needing writeback. We also 359 * need to pin the cache object to write back to. 360 */ 361 static int v9fs_set_page_dirty(struct page *page) 362 { 363 struct v9fs_inode *v9inode = V9FS_I(page->mapping->host); 364 366 } 367 #else 368 #define v9fs_set_page_dirty __set_page_dirty_nobuffers 369 #endif 370 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org