The patch titled
Subject: Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default
has been added to the -mm mm-hotfixes-unstable branch. Its filename is
kconfigdebug-disable-config_frame_warn-for-kmsan-by-default.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/kconfigdebug-disable-config_frame_warn-for-kmsan-by-default.patch
This patch will later appear in the mm-hotfixes-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: Alexander Potapenko <glider@xxxxxxxxxx>
Subject: Kconfig.debug: disable CONFIG_FRAME_WARN for KMSAN by default
Date: Mon, 24 Oct 2022 23:21:42 +0200
KMSAN adds a lot of instrumentation to the code, which results in
increased stack usage (up to 2048 bytes and more in some cases). It's
hard to predict how big the stack frames can be, so we disable the
warnings for KMSAN instead.
Link: https://lkml.kernel.org/r/20221024212144.2852069-3-glider@xxxxxxxxxx
Link: https://github.com/google/kmsan/issues/89
Signed-off-by: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Kees Cook <keescook@xxxxxxxxxxxx>
Cc: Masahiro Yamada <masahiroy@xxxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
lib/Kconfig.debug | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
--- a/lib/Kconfig.debug~kconfigdebug-disable-config_frame_warn-for-kmsan-by-default
+++ a/lib/Kconfig.debug
@@ -400,8 +400,9 @@ config FRAME_WARN
default 1536 if (!64BIT && XTENSA)
default 1024 if !64BIT
default 2048 if 64BIT
+ default 0 if KMSAN
help
- Tell gcc to warn at build time for stack frames larger than this.
+ Tell the compiler to warn at build time for stack frames larger than this.
Setting this too low will cause a lot of warnings.
Setting it to 0 disables the warning.
_
Patches currently in -mm which might be from glider@xxxxxxxxxx are
mm-kmsan-export-kmsan_copy_page_meta.patch
x86-purgatory-disable-kmsan-instrumentation.patch
kconfigdebug-disable-config_frame_warn-for-kmsan-by-default.patch
x86-asm-make-sure-__put_user_size-evaluates-pointer-once.patch
x86-fortify-kmsan-fix-kmsan-fortify-builds.patch
