Re: ipv4/tcp.c:4234:1: error: the frame size of 1152 bytes is larger than 1024 bytes [-Werror=frame-larger-than=]

From: Shuah Khan
Date: Wed Sep 08 2021 - 13:16:53 EST

On 9/8/21 11:05 AM, Arnd Bergmann wrote:
On Wed, Sep 8, 2021 at 4:12 PM Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx> wrote:
On 9/7/21 5:14 PM, Linus Torvalds wrote:
The KUNIT macros create all these individually reasonably small
initialized structures on stack, and when you have more than a small
handful of them the KUNIT infrastructure just makes the stack space
explode. Sometimes the compiler will be able to re-use the stack
slots, but it seems to be an iffy proposition to depend on it - it
seems to be a combination of luck and various config options.

I have been concerned about these macros creeping in for a while.
I will take a closer look and work with Brendan to come with a plan
to address it.

I've previously sent patches to turn off the structleak plugin for
any kunit test file to work around this, but only a few of those patches
got merged and new files have been added since. It would
definitely help to come up with a proper fix, but my structleak-disable
hack should be sufficient as a quick fix.

Looks like these are RFC patches and the discussion went cold. Let's pick
this back up and we can make progress.

-- Shuah