Re: [PATCH 3/4] staging: rtl8712: reduce stack usage, again

From: Willem de Bruijn
Date: Fri Jun 28 2019 - 15:52:46 EST


On Fri, Jun 28, 2019 at 8:41 AM Arnd Bergmann <arnd@xxxxxxxx> wrote:
>
> An earlier patch I sent reduced the stack usage enough to get
> below the warning limit, and I could show this was safe, but with
> GCC_PLUGIN_STRUCTLEAK_BYREF_ALL, it gets worse again because large stack
> variables in the same function no longer overlap:
>
> drivers/staging/rtl8712/rtl871x_ioctl_linux.c: In function 'translate_scan.isra.2':
> drivers/staging/rtl8712/rtl871x_ioctl_linux.c:322:1: error: the frame size of 1200 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]
>
> Split out the largest two blocks in the affected function into two
> separate functions and mark those noinline_for_stack.
>
> Fixes: 8c5af16f7953 ("staging: rtl8712: reduce stack usage")
> Fixes: 81a56f6dcd20 ("gcc-plugins: structleak: Generalize to all variable types")
> Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>

Reviewed-by: Willem de Bruijn <willemb@xxxxxxxxxx>