| Message ID | 20230621095905.31346-1-aleksandr.mikhalitsyn@canonical.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | docs: filesystems: idmappings: clarify from where idmappings are taken | expand |
Hi Alexander, kernel test robot noticed the following build warnings: [auto build test WARNING on vfs-idmapping/for-next] [also build test WARNING on linus/master v6.4-rc7 next-20230623] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Alexander-Mikhalitsyn/docs-filesystems-idmappings-clarify-from-where-idmappings-are-taken/20230621-180345 base: https://git.kernel.org/pub/scm/linux/kernel/git/vfs/idmapping.git for-next patch link: https://lore.kernel.org/r/20230621095905.31346-1-aleksandr.mikhalitsyn%40canonical.com patch subject: [PATCH] docs: filesystems: idmappings: clarify from where idmappings are taken reproduce: (https://download.01.org/0day-ci/archive/20230625/202306252253.qxHG1txo-lkp@intel.com/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@intel.com> | Closes: https://lore.kernel.org/oe-kbuild-all/202306252253.qxHG1txo-lkp@intel.com/ All warnings (new ones prefixed by >>): >> Documentation/filesystems/idmappings.rst:378: WARNING: Unexpected indentation. vim +378 Documentation/filesystems/idmappings.rst 375 376 From the implementation point it's worth mentioning how idmappings are represented. 377 All idmappings are taken from the corresponding user namespace. > 378 - caller's idmapping (usually taken from ``current_user_ns()``) 379 - filesystem's idmapping (``sb->s_user_ns``) 380 - mount's idmapping (``mnt_idmap(vfsmnt)``) 381
diff --git a/Documentation/filesystems/idmappings.rst b/Documentation/filesystems/idmappings.rst index ad6d21640576..c20382f8bbb0 100644 --- a/Documentation/filesystems/idmappings.rst +++ b/Documentation/filesystems/idmappings.rst @@ -373,6 +373,12 @@ kernel maps the caller's userspace id down into a kernel id according to the caller's idmapping and then maps that kernel id up according to the filesystem's idmapping. +From the implementation point it's worth mentioning how idmappings are represented. +All idmappings are taken from the corresponding user namespace. + - caller's idmapping (usually taken from ``current_user_ns()``) + - filesystem's idmapping (``sb->s_user_ns``) + - mount's idmapping (``mnt_idmap(vfsmnt)``) + Let's see some examples with caller/filesystem idmapping but without mount idmappings. This will exhibit some problems we can hit. After that we will revisit/reconsider these examples, this time using mount idmappings, to see how
Let's clarify from where we take idmapping of each type: - caller - filesystem - mount Cc: Jonathan Corbet <corbet@lwn.net> Cc: Christian Brauner <brauner@kernel.org> Cc: linux-fsdevel@vger.kernel.org Cc: linux-doc@vger.kernel.org Signed-off-by: Alexander Mikhalitsyn <aleksandr.mikhalitsyn@canonical.com> --- Documentation/filesystems/idmappings.rst | 6 ++++++ 1 file changed, 6 insertions(+)