|author||Joe Perches <firstname.lastname@example.org>||2015-05-05 16:23:38 -0700|
|committer||Linus Torvalds <email@example.com>||2015-05-05 17:10:10 -0700|
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 <firstname.lastname@example.org> Signed-off-by: Andrey Ryabinin <email@example.com> Signed-off-by: Andrew Morton <firstname.lastname@example.org> Signed-off-by: Linus Torvalds <email@example.com>
Diffstat (limited to 'lib')
1 files changed, 6 insertions, 2 deletions
diff --git a/lib/Kconfig.kasan b/lib/Kconfig.kasan
index 4fecaedc80a2..777eda7d1ab4 100644
@@ -10,8 +10,11 @@ config KASAN
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.