tree:   https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git netfs-folio-regions
head:   2f3fe780e9a44691136170536363c701b527d0e8
commit: 18149b3a78ab70d97039e2f729efa5bc7c3290ea [20/36] netfs: Initiate write request from a dirty region
config: i386-randconfig-s031-20210830 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.3-348-gf0e6938b-dirty
        # https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?id=18149b3a78ab70d97039e2f729efa5bc7c3290ea
        git remote add dhowells-fs https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git
        git fetch --no-tags dhowells-fs netfs-folio-regions
        git checkout 18149b3a78ab70d97039e2f729efa5bc7c3290ea
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 

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 >>):

   fs/netfs/objects.c: In function 'netfs_alloc_write_request':
>> fs/netfs/objects.c:128:27: error: implicit declaration of function 'netfs_is_cache_enabled' [-Werror=implicit-function-declaration]
     128 |  bool cached = !is_dio && netfs_is_cache_enabled(ctx);
         |                           ^~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +/netfs_is_cache_enabled +128 fs/netfs/objects.c

   120	
   121	struct netfs_write_request *netfs_alloc_write_request(struct address_space *mapping,
   122							      bool is_dio)
   123	{
   124		static atomic_t debug_ids;
   125		struct inode *inode = mapping->host;
   126		struct netfs_i_context *ctx = netfs_i_context(inode);
   127		struct netfs_write_request *wreq;
 > 128		bool cached = !is_dio && netfs_is_cache_enabled(ctx);
   129	
   130		wreq = kzalloc(sizeof(struct netfs_write_request), GFP_KERNEL);
   131		if (wreq) {
   132			wreq->mapping	= mapping;
   133			wreq->inode	= inode;
   134			wreq->netfs_ops	= ctx->ops;
   135			wreq->debug_id	= atomic_inc_return(&debug_ids);
   136			if (cached)
   137				__set_bit(NETFS_WREQ_WRITE_TO_CACHE, &wreq->flags);
   138			xa_init(&wreq->buffer);
   139			INIT_WORK(&wreq->work, netfs_writeback_worker);
   140			INIT_LIST_HEAD(&wreq->regions);
   141			rwlock_init(&wreq->regions_lock);
   142			refcount_set(&wreq->usage, 1);
   143			ctx->ops->init_wreq(wreq);
   144			netfs_stat(&netfs_n_wh_wreq);
   145			trace_netfs_ref_wreq(wreq->debug_id, 1, netfs_wreq_trace_new);
   146		}
   147	
   148		return wreq;
   149	}
   150	

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