Re: [PATCH 1/3] tmpfs: simplify constructing "security.foo" xattr names

[Greg Kroah-Hartman <gregkh@linuxfoundation.org>]

On Tue, May 26, 2026 at 10:46:12AM +0200, Miklos Szeredi wrote:
> [Cc: Greg KH]
> 
> On Mon, 25 May 2026 at 05:59, Calum Mackay <calum.mackay@oracle.com> wrote:
> >
> > hi Christian, Miklos,
> >
> > https://lore.kernel.org/all/177945382308.2991556.1256192774754909984.b4-ty@b4/
> >
> > > Date: Fri, 22 May 2026 14:43:43 +0200> On Tue, 19 May 2026 10:13:21 +0200, Miklos Szeredi wrote:
> > >> tmpfs: simplify constructing "security.foo" xattr names
> > >
> > > Thanks, this looks great!
> > >
> > > ---
> > >
> > > Applied to the vfs-7.2.misc branch of the vfs/vfs.git tree.
> > > Patches in the vfs-7.2.misc branch should appear in linux-next soon.
> > >
> > > Please report any outstanding bugs that were missed during review in a
> > > new review to the original patch series allowing us to drop it.
> > >
> > > It's encouraged to provide Acked-bys and Reviewed-bys even though the
> > > patch has now been applied. If possible patch trailers will be updated.
> > >
> > > Note that commit hashes shown below are subject to change due to rebase,
> > > trailer updates or similar. If in doubt, please check the listed branch.
> > >
> > > tree:   https://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs.git
> > > branch: vfs-7.2.misc
> > >
> > > [1/3] tmpfs: simplify constructing "security.foo" xattr names
> > >       https://git.kernel.org/vfs/vfs/c/aba5853b137b
> > > [2/3] simple_xattr: change interface to pass struct simple_xattrs **
> > >       https://git.kernel.org/vfs/vfs/c/1cd9d2387c05
> > > [3/3] simpe_xattr: use per-sb cache
> > >       https://git.kernel.org/vfs/vfs/c/12e9e3cd03b5
> >
> >
> > I have been doing some testing of Chuck's nfsd-testing tree, which
> > includes some vfs changes.
> >
> > The test systems are reliably crashing, in what looks like it might
> > possibly be something related to these three patches.
> 
> Calum, thanks for the report.
> 
> Relevant part of call trace is:
> 
> kernfs_new_node
>   __kernfs_new_node
>     security_kernfs_init_security
>       selinux_kernfs_init_security
>         kernfs_xattr_set
>           kernfs_root
> 
> Since __parent is assigned after security_kernfs_init_security() gets
> called, kernfs_root() will return NULL.
> 
> Greg, any idea about dealing with this?

Don't call this so early?  :)

I really don't know, sorry.

greg k-h