From 3f181b4d8652f7bcd7e9932c7307b8ecd4d87cf6 Mon Sep 17 00:00:00 2001 From: Andrey Ryabinin Date: Thu, 22 Oct 2015 13:32:24 -0700 Subject: [PATCH] lib/Kconfig.debug: disable -Wframe-larger-than warnings with KASAN=y When the kernel compiled with KASAN=y, GCC adds redzones for each variable on stack. This enlarges function's stack frame and causes: 'warning: the frame size of X bytes is larger than Y bytes' The worst case I've seen for now is following: ../net/wireless/nl80211.c: In function `nl80211_send_wiphy': ../net/wireless/nl80211.c:1731:1: warning: the frame size of 5448 bytes is larger than 2048 bytes [-Wframe-larger-than=] That kind of warning becomes useless with KASAN=y. It doesn't necessarily indicate that there is some problem in the code, thus we should turn it off. (The KASAN=y stack size in increased from 16k to 32k for this reason) Signed-off-by: Andrey Ryabinin Reported-by: Fengguang Wu Acked-by: Abylay Ospan Cc: Andi Kleen Cc: Ingo Molnar Cc: Mauro Carvalho Chehab Cc: Kozlov Sergey Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index ab76b99adc85..1d1521c26302 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -197,6 +197,7 @@ config ENABLE_MUST_CHECK config FRAME_WARN int "Warn for stack frames larger than (needs gcc 4.4)" range 0 8192 + default 0 if KASAN default 1024 if !64BIT default 2048 if 64BIT help -- 2.20.1