Re: [PATCH net-next] airo: work around stack usage warning

From: Kalle Valo
Date: Sat Apr 17 2021 - 14:03:22 EST


Arnd Bergmann <arnd@xxxxxxxxxx> wrote:

> From: Arnd Bergmann <arnd@xxxxxxxx>
>
> gcc-11 with KASAN on 32-bit arm produces a warning about a function
> that needs a lot of stack space:
>
> drivers/net/wireless/cisco/airo.c: In function 'setup_card.constprop':
> drivers/net/wireless/cisco/airo.c:3960:1: error: the frame size of 1512 bytes is larger than 1400 bytes [-Werror=frame-larger-than=]
>
> Most of this is from a single large structure that could be dynamically
> allocated or moved into the per-device structure. However, as the callers
> all seem to have a fairly well bounded call chain, the easiest change
> is to pull out the part of the function that needs the large variables
> into a separate function and mark that as noinline_for_stack. This does
> not reduce the total stack usage, but it gets rid of the warning and
> requires minimal changes otherwise.
>
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Patch applied to wireless-drivers-next.git, thanks.

7909a590eba6 airo: work around stack usage warning

--
https://patchwork.kernel.org/project/linux-wireless/patch/20210323131634.2669455-1-arnd@xxxxxxxxxx/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches