mirror of
https://github.com/edk2-porting/linux-next.git
synced 2024-12-19 02:34:01 +08:00
5dff03813f
By default 3-level paging is used when the kernel is compiled with kasan support. Add 4-level paging option to support systems with more then 3TB of physical memory and to cover 4-level paging specific code with kasan as well. Reviewed-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
78 lines
2.5 KiB
Plaintext
78 lines
2.5 KiB
Plaintext
config HAVE_ARCH_KASAN
|
|
bool
|
|
|
|
if HAVE_ARCH_KASAN
|
|
|
|
config KASAN
|
|
bool "KASan: runtime memory debugger"
|
|
depends on (SLUB && SYSFS) || (SLAB && !DEBUG_SLAB)
|
|
select SLUB_DEBUG if SLUB
|
|
select CONSTRUCTORS
|
|
select STACKDEPOT
|
|
help
|
|
Enables kernel address sanitizer - runtime memory debugger,
|
|
designed to find out-of-bounds accesses and use-after-free bugs.
|
|
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.
|
|
Currently CONFIG_KASAN doesn't work with CONFIG_DEBUG_SLAB
|
|
(the resulting kernel does not boot).
|
|
|
|
config KASAN_EXTRA
|
|
bool "KAsan: extra checks"
|
|
depends on KASAN && DEBUG_KERNEL && !COMPILE_TEST
|
|
help
|
|
This enables further checks in the kernel address sanitizer, for now
|
|
it only includes the address-use-after-scope check that can lead
|
|
to excessive kernel stack usage, frame size warnings and longer
|
|
compile time.
|
|
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81715 has more
|
|
|
|
|
|
choice
|
|
prompt "Instrumentation type"
|
|
depends on KASAN
|
|
default KASAN_OUTLINE
|
|
|
|
config KASAN_OUTLINE
|
|
bool "Outline instrumentation"
|
|
help
|
|
Before every memory access compiler insert function call
|
|
__asan_load*/__asan_store*. These functions performs check
|
|
of shadow memory. This is slower than inline instrumentation,
|
|
however it doesn't bloat size of kernel's .text section so
|
|
much as inline does.
|
|
|
|
config KASAN_INLINE
|
|
bool "Inline instrumentation"
|
|
help
|
|
Compiler directly inserts code checking shadow memory before
|
|
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
|
|
|
|
config KASAN_S390_4_LEVEL_PAGING
|
|
bool "KASan: use 4-level paging"
|
|
depends on KASAN && S390
|
|
help
|
|
Compiling the kernel with KASan disables automatic 3-level vs
|
|
4-level paging selection. 3-level paging is used by default (up
|
|
to 3TB of RAM with KASan enabled). This options allows to force
|
|
4-level paging instead.
|
|
|
|
config TEST_KASAN
|
|
tristate "Module for testing kasan for bug detection"
|
|
depends on m && KASAN
|
|
help
|
|
This is a test module doing various nasty things like
|
|
out of bounds accesses, use after free. It is useful for testing
|
|
kernel debugging features like kernel address sanitizer.
|
|
|
|
endif
|