Re: [PATCH v1] 9p: Fix mkdir to return NULL on success

[Hongling Zeng]

 Hi Dominique,

  Thanks for picking this up!

  I received David feedback suggesting to simplify v9fs_vfs_mkdir()
  by removing the 'err' variable and using ERR_CAST(). Since v1 is
  already merged, would you still like a v2, or shall I submit it 
separately?

  Best regards,
  Hongling
在 2026年05月19日 20:21, Dominique Martinet 写道:
> Hongling Zeng wrote on Mon, May 11, 2026 at 02:18:30PM +0800:
> > When mkdir succeeds, v9fs_vfs_mkdir_dotl() and v9fs_vfs_mkdir() return
> > ERR_PTR(0) which is incorrect. They should return NULL instead for
> > success and ERR_PTR() only with negative error codes for failure.
> >
> > Return NULL instead of passing to ERR_PTR while err is zero
> > Fixes smatch warnings:
> >    fs/9p/vfs_inode_dotl.c:420 v9fs_vfs_mkdir_dotl() warn: passing zero to 'ERR_PTR'
> >    fs/9p/vfs_inode.c:695 v9fs_vfs_mkdir() warn: passing zero to 'ERR_PTR'
> >
> > This change does not alter the runtime behavior since ERR_PTR(0) and NULL
> > are equivalent. However, it improves code readability and silences static
> > analyzer warnings.
> >
> > Fixes: 88d5baf69082 ("Change inode_operations.mkdir to return struct dentry *")
> > Acked-by: Christian Schoenebeck <linux_oss@xxxxxxxxxxxxx>
> > Signed-off-by: Hongling Zeng <zenghongling@xxxxxxxxxx>
> Thanks, I've picked this up with s/Fix/make/ in the commit subject, as I
> (subjectively) don't consider this a fix given it's only a style change