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For the vmalloc area, I checked the >> call points on the vfs side, such as dentry_string_cmp() or hash_name(). >> Their "names addr" are all assigned by kmalloc(), so there should be no >> corresponding issues. But I'm not familiar with the other calling >> points... > > Pathname might be a symlink body, sitting in page cache or whatever > ->get_link() has returned... > Thanks for the additional explanation — I indeed hadn't considered symlinks. But if the data is in the page cache, as I understand it, its address wouldn't be in the vmalloc area, right? However, for other .get_link implementations, it's true that there's no guarantee. Thanks, Zizhi Wo