Hi yu,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on block/for-next]
[also build test ERROR on v5.6-rc1 next-20200212]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]

url:    https://github.com/0day-ci/linux/commits/yu-kuai/block-rename-q-debugfs_dir-in-blk_unregister_queue/20200213-091022
base:   https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-next
config: um-x86_64_defconfig (attached as .config)
compiler: gcc-7 (Debian 7.5.0-4) 7.5.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=um SUBARCH=x86_64

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

All errors (new ones prefixed by >>):

   block/blk-sysfs.c: In function 'blk_prepare_release_queue':
>> block/blk-sysfs.c:1030:22: error: 'struct request_queue' has no member named 'debugfs_dir'
     if (IS_ERR_OR_NULL(q->debugfs_dir))
                         ^~
   block/blk-sysfs.c:1031:11: error: 'struct request_queue' has no member named 'debugfs_dir'
      return q->debugfs_dir;
              ^~
>> block/blk-sysfs.c:1035:24: error: 'blk_debugfs_root' undeclared (first use in this function); did you mean 'blk_mq_debugfs_attr'?
      new = debugfs_rename(blk_debugfs_root, q->debugfs_dir,
                           ^~~~~~~~~~~~~~~~
                           blk_mq_debugfs_attr
   block/blk-sysfs.c:1035:24: note: each undeclared identifier is reported only once for each function it appears in
   block/blk-sysfs.c:1035:43: error: 'struct request_queue' has no member named 'debugfs_dir'
      new = debugfs_rename(blk_debugfs_root, q->debugfs_dir,
                                              ^~
   block/blk-sysfs.c: In function 'blk_unregister_queue':
   block/blk-sysfs.c:1070:3: error: 'struct request_queue' has no member named 'debugfs_dir'
     q->debugfs_dir = blk_prepare_release_queue(q);
      ^~

vim +1030 block/blk-sysfs.c

  1014	
  1015	/*
  1016	 * blk_prepare_release_queue - rename q->debugfs_dir
  1017	 * @q: request_queue of which the dir to be renamed belong to.
  1018	 *
  1019	 * Because the final release of request_queue is in a workqueue, the
  1020	 * cleanup might not been finished yet while the same device start to
  1021	 * create. It's not correct if q->debugfs_dir still exist while trying
  1022	 * to create a new one.
  1023	 */
  1024	static struct dentry *blk_prepare_release_queue(struct request_queue *q)
  1025	{
  1026		struct dentry *new = NULL;
  1027		char name[DNAME_INLINE_LEN];
  1028		int i = 0;
  1029	
> 1030		if (IS_ERR_OR_NULL(q->debugfs_dir))
  1031			return q->debugfs_dir;
  1032	
  1033		while (new == NULL) {
  1034			sprintf(name, "ready_to_remove_%d", i++);
> 1035			new = debugfs_rename(blk_debugfs_root, q->debugfs_dir,
  1036					     blk_debugfs_root, name);
  1037		}
  1038	
  1039		return new;
  1040	}
  1041	

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