[PATCH v2 0/8] fs: add some missing ctime updates

[Al Viro]

On Mon, Jun 12, 2023 at 06:45:16AM -0400, Jeff Layton wrote:
> Jeff Layton (8):
>   ibmvmc: update ctime in conjunction with mtime on write
>   usb: update the ctime as well when updating mtime after an ioctl
>   autofs: set ctime as well when mtime changes on a dir
>   bfs: update ctime in addition to mtime when adding entries
>   efivarfs: update ctime when mtime changes on a write
>   exfat: ensure that ctime is updated whenever the mtime is
>   apparmor: update ctime whenever the mtime changes on an inode
>   cifs: update the ctime on a partial page write
> 
>  drivers/misc/ibmvmc.c             |  2 +-
>  drivers/usb/core/devio.c          | 16 ++++++++--------
>  fs/autofs/root.c                  |  6 +++---
>  fs/bfs/dir.c                      |  2 +-
>  fs/efivarfs/file.c                |  2 +-
>  fs/exfat/namei.c                  |  8 ++++----
>  fs/smb/client/file.c              |  2 +-
>  security/apparmor/apparmorfs.c    |  7 +++++--
>  security/apparmor/policy_unpack.c | 11 +++++++----
>  9 files changed, 31 insertions(+), 25 deletions(-)

As a possible followup (again, apologies for being MIA for months):
touch_cmtime(inode)...