[GIT PULL] Landlock updates for v6.5

[Mickaël Salaün]

Hi Linus,

This PR adds support for Landlock to UML.  In fact, this fixes the way
hostfs manages inodes according to the underlying filesystem [1].  They
are now properly handled as for other filesystems, which enables to
support Landlock (and probably other features).  This PR also extends
Landlock's tests with 6 pseudo filesystems, including hostfs.

This PR can lead to a trivial merge conflict with tip [2] where one of
Thomas's commit adds ARCH_HAS_CPU_FINALIZE_INIT and one of mine removes
ARCH_EPHEMERAL_INODES in arch/um/Kconfig.

Please pull these changes for v6.5-rc1 .  These commits merged cleanly
with v6.4, and have been successfully tested in the latest linux-next
releases for a few weeks.

[1] https://lore.kernel.org/all/20230612191430.339153-1-mic@digikod.net/
[2] https://lore.kernel.org/all/b57481af-5824-72f7-d20f-cfd78fcde519@digikod.net/

Regards,
 Mickaël

--
The following changes since commit 858fd168a95c5b9669aac8db6c14a9aeab446375:

  Linux 6.4-rc6 (2023-06-11 14:35:30 -0700)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/mic/linux.git tags/landlock-6.5-rc1

for you to fetch changes up to 35ca4239929737bdc021ee923f97ebe7aff8fcc4:

  selftests/landlock: Add hostfs tests (2023-06-12 21:26:23 +0200)

----------------------------------------------------------------
Landlock updates for v6.5-rc1

----------------------------------------------------------------
Mickaël Salaün (6):
      hostfs: Fix ephemeral inodes
      selftests/landlock: Don't create useless file layouts
      selftests/landlock: Add supports_filesystem() helper
      selftests/landlock: Make mounts configurable
      selftests/landlock: Add tests for pseudo filesystems
      selftests/landlock: Add hostfs tests

 arch/Kconfig                               |   7 -
 arch/um/Kconfig                            |   1 -
 fs/hostfs/hostfs.h                         |   1 +
 fs/hostfs/hostfs_kern.c                    | 213 ++++++++--------
 fs/hostfs/hostfs_user.c                    |   1 +
 security/landlock/Kconfig                  |   2 +-
 tools/testing/selftests/landlock/config    |   9 +-
 tools/testing/selftests/landlock/config.um |   1 +
 tools/testing/selftests/landlock/fs_test.c | 387 +++++++++++++++++++++++++++--
 9 files changed, 478 insertions(+), 144 deletions(-)
 create mode 100644 tools/testing/selftests/landlock/config.um