The patch titled Subject: kasan: always respect CONFIG_KASAN_STACK has been added to the -mm tree. Its filename is kasan-always-respect-config_kasan_stack.patch This patch should soon appear at https://ozlabs.org/~akpm/mmots/broken-out/kasan-always-respect-config_kasan_stack.patch and later at https://ozlabs.org/~akpm/mmotm/broken-out/kasan-always-respect-config_kasan_stack.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Nathan Chancellor <nathan@xxxxxxxxxx> Subject: kasan: always respect CONFIG_KASAN_STACK Currently, the asan-stack parameter is only passed along if CFLAGS_KASAN_SHADOW is not empty, which requires KASAN_SHADOW_OFFSET to be defined in Kconfig so that the value can be checked. In RISC-V's case, KASAN_SHADOW_OFFSET is not defined in Kconfig, which means that asan-stack does not get disabled with clang even when CONFIG_KASAN_STACK is disabled, resulting in large stack warnings with allmodconfig: drivers/video/fbdev/omap2/omapfb/displays/panel-lgphilips-lb035q02.c:117:12: error: stack frame size (14400) exceeds limit (2048) in function 'lb035q02_connect' [-Werror,-Wframe-larger-than] static int lb035q02_connect(struct omap_dss_device *dssdev) ^ 1 error generated. Ensure that the value of CONFIG_KASAN_STACK is always passed along to the compiler so that these warnings do not happen when CONFIG_KASAN_STACK is disabled. Link: https://github.com/ClangBuiltLinux/linux/issues/1453 References: 6baec880d7a5 ("kasan: turn off asan-stack for clang-8 and earlier") Link: https://lkml.kernel.org/r/20210922205525.570068-1-nathan@xxxxxxxxxx Signed-off-by: Nathan Chancellor <nathan@xxxxxxxxxx> Reviewed-by: Marco Elver <elver@xxxxxxxxxx> Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Konovalov <andreyknvl@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- scripts/Makefile.kasan | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/scripts/Makefile.kasan~kasan-always-respect-config_kasan_stack +++ a/scripts/Makefile.kasan @@ -33,10 +33,11 @@ else CFLAGS_KASAN := $(CFLAGS_KASAN_SHADOW) \ $(call cc-param,asan-globals=1) \ $(call cc-param,asan-instrumentation-with-call-threshold=$(call_threshold)) \ - $(call cc-param,asan-stack=$(stack_enable)) \ $(call cc-param,asan-instrument-allocas=1) endif +CFLAGS_KASAN += $(call cc-param,asan-stack=$(stack_enable)) + endif # CONFIG_KASAN_GENERIC ifdef CONFIG_KASAN_SW_TAGS _ Patches currently in -mm which might be from nathan@xxxxxxxxxx are kasan-always-respect-config_kasan_stack.patch