Re: [PATCH v2] x86/Kconfig: Fix allyesconfig

From: Guenter Roeck
Date: Wed Apr 16 2025 - 20:17:13 EST


On 4/16/25 17:03, Andrew Morton wrote:
On Wed, 16 Apr 2025 16:05:59 -0700 Guenter Roeck <linux@xxxxxxxxxxxx> wrote:

64-bit allyesconfig builds fail with

x86_64-linux-ld: kernel image bigger than KERNEL_IMAGE_SIZE

Bisect points to commit 6f110a5e4f99 ("Disable SLUB_TINY for build
testing") as the responsible commit. Reverting that patch does indeed
fix the problem. Further analysis shows that disabling SLUB_TINY enables
KASAN, and that KASAN is responsible for the image size increase.

Solve the build problem by disabling KASAN for test builds.


Excluding KASAN from COMPILE_TEST builds is regrettable.

Can we address this some other way? One way might be to alter or
disable the KERNEL_IMAGE_SIZE check if COMPILE_TEST? That will be sad
for anyone who tries to boot a COMPILE_TEST kernel, but who the heck
does that?

I tried increasing the limit. It didn't work. With the RFC I sent earlier
I made it dependent on allmodconfig, but Linus said I should just disable
it for test builds (which was the cases anyway until commit 6f110a5e4f99).

Personally I don't have a preference either way. I can also do nothing and
stop testing allyesconfig. That would help reducing the load on my testbed,
so I would be all for it.

Guenter