Re: Clarifying confusion of our variable placement rules caused by cleanup.h

On Tue, 18 Nov 2025 10:38:20 -0800
Linus Torvalds <[email protected]> wrote:

>         struct x509_parse_context *ctx __free(kfree) = NULL;
>         ... other code ...
>         ctx = kzalloc(sizeof(struct x509_parse_context), GFP_KERNEL);
> 
> where you have now split up the whole "this is allocated by kmalloc,
> and free'd by kfree" into two different sections that are not next to
> each other.

I've been doing the above, and was even going to recommend it to James. But
if it is preferred to declare the __free() variables where they are
allocated, I'd be much happier.

I think the code could also be better optimized? I haven't run an objcopy to
confirm but now early exits do not require calling the __free() function on
NULL pointers.

Most of my code allocates near the top where I don't find this a problem,
but I do have a few places of:

	struct foo *var __free(kfree) = NULL;

	if (ret < 0)
		return -ERROR;

	[ several more error exits ]

	var = kmalloc(..);

-- Steve