From 01e76903f655a4d88c2e09d3182436c65f6e1213 Mon Sep 17 00:00:00 2001 From: Joe Perches Date: Tue, 5 May 2015 16:23:38 -0700 Subject: kasan: show gcc version requirements in Kconfig and Documentation The documentation shows a need for gcc > 4.9.2, but it's really >=. The Kconfig entries don't show require versions so add them. Correct a latter/later typo too. Also mention that gcc 5 required to catch out of bounds accesses to global and stack variables. Signed-off-by: Joe Perches Signed-off-by: Andrey Ryabinin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Kconfig.kasan | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) (limited to 'lib') diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan index 4fecaedc80a2..777eda7d1ab4 100644 --- a/lib/Kconfig.kasan +++ b/lib/Kconfig.kasan @@ -10,8 +10,11 @@ config KASAN help Enables kernel address sanitizer - runtime memory debugger, designed to find out-of-bounds accesses and use-after-free bugs. - This is strictly debugging feature. It consumes about 1/8 - of available memory and brings about ~x3 performance slowdown. + This is strictly a debugging feature and it requires a gcc version + of 4.9.2 or later. Detection of out of bounds accesses to stack or + global variables requires gcc 5.0 or later. + This feature consumes about 1/8 of available memory and brings about + ~x3 performance slowdown. For better error detection enable CONFIG_STACKTRACE, and add slub_debug=U to boot cmdline. @@ -40,6 +43,7 @@ config KASAN_INLINE memory accesses. This is faster than outline (in some workloads it gives about x2 boost over outline instrumentation), but make kernel's .text size much bigger. + This requires a gcc version of 5.0 or later. endchoice -- cgit v1.2.3