Re: lib/crypto/chacha.c:65:1: warning: the frame size of 1604 bytes is larger than 1024 bytes

[Linus Torvalds]

On Thu, Aug 27, 2020 at 10:34 AM Linus Torvalds
<torvalds@xxxxxxxxxxxxxxxxxxxx> wrote:
>
> How are you guys testing? I have UBSAN and GCOV on, and don't see
> crazy frames on either i386 or x86-64.

Oh, never mind. I also have COMPILE_TEST on, so it ends up disabling
GCOV_PROFILE_ALL and UBSAN_SANITIZE_ALL.

And yeah, this seems to be a gcc bug. It generates a ton of stack
slots for temporaries. It's -fsanitize=object-size that seems to do
it.

And "-fstack-reuse=all" doesn't seem to make any difference.

So I think

 (a) our stack size check is good to catch this

 (b) gcc and -fsanitize=object-size is basically an unusable combination

and it's not a bug in the kernel.

                Linus