This adds a super basic version just to get the mechanism going, along with sample usage. The macro set is incomplete (e.g., lack of locking macros) and dump_inode routine fails to dump any state yet, to be implemented(tm). I think despite the primitive state this is complete enough to start sprinkling asserts as necessary. v3: - move dump_inode to fs/inode.c - s/failed/encountered/ - pr_warn instead of pr_crit, matches dump_mapping v2: - correct may_open - fixed up condition reporting: before: VFS_WARN_ON_INODE(__builtin_choose_expr((sizeof(int) == sizeof(*(8 ? ((void *)((long)(__builtin_strlen(link)) * 0l)) : (int *)8))), __builtin_strlen(link), __fortify_strlen(link)) != linklen) failed for inode ff32f7c350c8aec8 after: VFS_WARN_ON_INODE(strlen(link) != linklen) failed for inode ff2b81ddca13f338 Mateusz Guzik (3): vfs: add initial support for CONFIG_VFS_DEBUG vfs: catch invalid modes in may_open() vfs: use the new debug macros in inode_set_cached_link() fs/inode.c | 12 +++++++++++ fs/namei.c | 2 ++ include/linux/fs.h | 16 +++----------- include/linux/vfsdebug.h | 45 ++++++++++++++++++++++++++++++++++++++++ lib/Kconfig.debug | 9 ++++++++ 5 files changed, 71 insertions(+), 13 deletions(-) create mode 100644 include/linux/vfsdebug.h -- 2.43.0