Honestly, I hate this. In particular, I intensely dislike that horrendous 'SIZE' parameter to those helper macros, and this just needs to die.
The argument for that horror is also just silly: On Fri, 21 Nov 2025 at 17:43, Kees Cook <[email protected]> wrote: > > These each return the newly allocated pointer to the type (which may be > NULL on failure). For cases where the total size of the allocation is > needed, the kmalloc_obj_sz(), kmalloc_objs_sz(), and kmalloc_flex_sz() > family of macros can be used. For example: > > size = struct_size(ptr, flex_member, count); > ptr = kmalloc(size, gfp); > > becomes: > > ptr = kmalloc_flex_sz(*ptr, flex_member, count, gfp, &size); That thing is ACTIVELY WORSE than the code it replaces. One of them makes sense and is legible toi a normal human. The other does not. The alleged advantage is apparently that you can do it on one line, but when that one line is just horrible garbage, that is not an advantyage at all. And the impact of that crazy SIZE on the macro expansions makes the whole thing entirely illegible. I will not merge anything this broken. The whole "limit to pre-defined size" argument is also just crazy, because now the SIZE parameter suddenly gets a second meaning. EVEN WORSE. Finally, I think the parts of this that aren't wrong are too limited, and do not go far enough. Because once you give that "alloc_obj()" an actual type, it should take the alignment of the type into account too. I also think this part: + typeof(VAR) *__obj_ptr = NULL; \ + if (!WARN_ON_ONCE(!__can_set_flex_counter(__obj_ptr->FAM, __count)) && \ absolutely needs to die. You just set __obj_ptr to NULL, and then you use __obj_ptr->FAM. Now, it so happens that __can_set_flex_counter() only cares about the *type*, but dammit, this kind of code sequence is simply not acceptable, and it needs to make that *explicit* by using sane syntax like perhaps just spelling that out, using VAR, not that NULL value. IOW. making it use something like "typeof(VAR.FAM)" might work. Not that crazy garbage. I never want to see this kind of horrendous patch again. Everything about it just screamed "disgusting". Linus
