Hi Boris,

I love your patch! Perhaps something to improve:

[auto build test WARNING on kdave/for-next]
[cannot apply to v5.12 next-20210505]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Boris-Burkov/btrfs-add-compat_flags-to-btrfs_inode_item/20210506-042129
base:   https://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux.git for-next
config: x86_64-randconfig-a014-20210505 (attached as .config)
compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 8f5a2a5836cc8e4c1def2bdeb022e7b496623439)
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://github.com/0day-ci/linux/commit/f61feb554b6d2710f17960a9775bf9ba41bb2dc2
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Boris-Burkov/btrfs-add-compat_flags-to-btrfs_inode_item/20210506-042129
        git checkout f61feb554b6d2710f17960a9775bf9ba41bb2dc2
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

quoted

fs/btrfs/verity.c:434:6: warning: variable 'ret' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]

           if (desc != NULL) {
               ^~~~~~~~~~~~
   fs/btrfs/verity.c:470:9: note: uninitialized use occurs here
           return ret;
                  ^~~
   fs/btrfs/verity.c:434:2: note: remove the 'if' if its condition is always true
           if (desc != NULL) {
           ^~~~~~~~~~~~~~~~~~
   fs/btrfs/verity.c:432:9: note: initialize the variable 'ret' to silence this warning
           int ret;
                  ^
                   = 0
   1 warning generated.


vim +434 fs/btrfs/verity.c

   417	
   418	/*
   419	 * fsverity op that ends enabling verity.
   420	 * fsverity calls this when it's done with all of the pages in the file
   421	 * and all of the merkle items have been inserted.  We write the
   422	 * descriptor and update the inode in the btree to reflect its new life
   423	 * as a verity file.
   424	 */
   425	static int btrfs_end_enable_verity(struct file *filp, const void *desc,
   426					  size_t desc_size, u64 merkle_tree_size)
   427	{
   428		struct btrfs_trans_handle *trans;
   429		struct inode *inode = file_inode(filp);
   430		struct btrfs_root *root = BTRFS_I(inode)->root;
   431		struct btrfs_verity_descriptor_item item;
   432		int ret;
   433	
 > 434		if (desc != NULL) {
   435			/* write out the descriptor item */
   436			memset(&item, 0, sizeof(item));
   437			btrfs_set_stack_verity_descriptor_size(&item, desc_size);
   438			ret = write_key_bytes(BTRFS_I(inode),
   439					      BTRFS_VERITY_DESC_ITEM_KEY, 0,
   440					      (const char *)&item, sizeof(item));
   441			if (ret)
   442				goto out;
   443			/* write out the descriptor itself */
   444			ret = write_key_bytes(BTRFS_I(inode),
   445					      BTRFS_VERITY_DESC_ITEM_KEY, 1,
   446					      desc, desc_size);
   447			if (ret)
   448				goto out;
   449	
   450			/* update our inode flags to include fs verity */
   451			trans = btrfs_start_transaction(root, 1);
   452			if (IS_ERR(trans)) {
   453				ret = PTR_ERR(trans);
   454				goto out;
   455			}
   456			BTRFS_I(inode)->compat_flags |= BTRFS_INODE_VERITY;
   457			btrfs_sync_inode_flags_to_i_flags(inode);
   458			ret = btrfs_update_inode(trans, root, BTRFS_I(inode));
   459			btrfs_end_transaction(trans);
   460		}
   461	
   462	out:
   463		if (desc == NULL || ret) {
   464			/* If we failed, drop all the verity items */
   465			drop_verity_items(BTRFS_I(inode), BTRFS_VERITY_DESC_ITEM_KEY);
   466			drop_verity_items(BTRFS_I(inode), BTRFS_VERITY_MERKLE_ITEM_KEY);
   467		} else
   468			btrfs_set_fs_compat_ro(root->fs_info, VERITY);
   469		clear_bit(BTRFS_INODE_VERITY_IN_PROGRESS, &BTRFS_I(inode)->runtime_flags);
   470		return ret;
   471	}
   472	

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