Re: [PATCH v3 0/9] memfd: add sealing to hugetlb-backed memory

[Mike Kravetz <mike.kravetz@oracle.com>]

+Cc: Andrew, Michal, David

Are there any other comments on this patch series from Marc-André?  Is anything
else needed to move forward?

I have reviewed the patches in the series.  David Herrmann (the original
memfd_create/file sealing author) has also taken a look at the patches.

One outstanding issue is sorting out the config option dependencies.  Although,
IMO this is not a strict requirement for this series.  I have addressed this
issue in a follow on series:
http://lkml.kernel.org/r/20171109014109.21077-1-mike.kravetz@oracle.com

-- 
Mike Kravetz


On 11/07/2017 04:27 AM, Marc-André Lureau wrote:
> Hi,
> 
> Recently, Mike Kravetz added hugetlbfs support to memfd. However, he
> didn't add sealing support. One of the reasons to use memfd is to have
> shared memory sealing when doing IPC or sharing memory with another
> process with some extra safety. qemu uses shared memory & hugetables
> with vhost-user (used by dpdk), so it is reasonable to use memfd
> now instead for convenience and security reasons.
> 
> Thanks!
> 
> v3:
> - do remaining MFD_DEF_SIZE/mfd_def_size substitutions
> - fix missing unistd.h include in common.c
> - tweaked a bit commit message prefixes
> - added reviewed-by tags
> 
> v2:
> - add "memfd-hugetlb:" prefix in memfd-test
> - run fuse test on hugetlb backend memory
> - rename function memfd_file_get_seals() -> memfd_file_seals_ptr()
> - update commit messages
> - added reviewed-by tags
> 
> RFC->v1:
> - split rfc patch, after early review feedback
> - added patch for memfd-test changes
> - fix build with hugetlbfs disabled
> - small code and commit messages improvements
> 
> Marc-André Lureau (9):
>   shmem: unexport shmem_add_seals()/shmem_get_seals()
>   shmem: rename functions that are memfd-related
>   hugetlb: expose hugetlbfs_inode_info in header
>   hugetlb: implement memfd sealing
>   shmem: add sealing support to hugetlb-backed memfd
>   memfd-test: test hugetlbfs sealing
>   memfd-test: add 'memfd-hugetlb:' prefix when testing hugetlbfs
>   memfd-test: move common code to a shared unit
>   memfd-test: run fuse test on hugetlb backend memory
> 
>  fs/fcntl.c                                     |   2 +-
>  fs/hugetlbfs/inode.c                           |  39 +++--
>  include/linux/hugetlb.h                        |  11 ++
>  include/linux/shmem_fs.h                       |   6 +-
>  mm/shmem.c                                     |  59 ++++---
>  tools/testing/selftests/memfd/Makefile         |   5 +
>  tools/testing/selftests/memfd/common.c         |  46 ++++++
>  tools/testing/selftests/memfd/common.h         |   9 ++
>  tools/testing/selftests/memfd/fuse_test.c      |  44 +++--
>  tools/testing/selftests/memfd/memfd_test.c     | 212 ++++---------------------
>  tools/testing/selftests/memfd/run_fuse_test.sh |   2 +-
>  tools/testing/selftests/memfd/run_tests.sh     |   1 +
>  12 files changed, 200 insertions(+), 236 deletions(-)
>  create mode 100644 tools/testing/selftests/memfd/common.c
>  create mode 100644 tools/testing/selftests/memfd/common.h
>