"Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> writes: > I am confused what is going on with ext4 and f2fs. I think they > are calling d_invalidate when all they need to call is d_drop. ext4 and f2f2 are buggy in how they call d_invalidate, if I am reading the code correctly. d_invalidate calls detach_mounts. detach_mounts relies on setting D_CANT_MOUNT on the top level dentry to prevent races with new mounts. ext4 and f2fs (in their case insensitive code) are calling d_invalidate before dont_mount has been called to set D_CANT_MOUNT. Eric