KASAN is supported on 32-bit powerpc and the docs should reflect this. Suggested-by: Christophe Leroy <christophe.le...@csgroup.eu> Reviewed-by: Christophe Leroy <christophe.le...@csgroup.eu> Signed-off-by: Daniel Axtens <d...@axtens.net> --- Documentation/dev-tools/kasan.rst | 8 ++++++-- Documentation/powerpc/kasan.txt | 12 ++++++++++++ 2 files changed, 18 insertions(+), 2 deletions(-) create mode 100644 Documentation/powerpc/kasan.txt
diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index a8c3e0cff88d..2cfd5d9068c0 100644 --- a/Documentation/dev-tools/kasan.rst +++ b/Documentation/dev-tools/kasan.rst @@ -36,7 +36,8 @@ Both software KASAN modes work with SLUB and SLAB memory allocators, while the hardware tag-based KASAN currently only supports SLUB. Currently, generic KASAN is supported for the x86_64, arm, arm64, xtensa, s390, -and riscv architectures, and tag-based KASAN modes are supported only for arm64. +and riscv architectures. It is also supported on 32-bit powerpc kernels. +Tag-based KASAN modes are supported only for arm64. Usage ----- @@ -334,7 +335,10 @@ CONFIG_KASAN_VMALLOC With ``CONFIG_KASAN_VMALLOC``, KASAN can cover vmalloc space at the cost of greater memory usage. Currently, this is supported on x86, -riscv, s390, and powerpc. +riscv, s390, and 32-bit powerpc. + +It is optional, except on 32-bit powerpc kernels with module support, +where it is required. This works by hooking into vmalloc and vmap and dynamically allocating real shadow memory to back the mappings. diff --git a/Documentation/powerpc/kasan.txt b/Documentation/powerpc/kasan.txt new file mode 100644 index 000000000000..26bb0e8bb18c --- /dev/null +++ b/Documentation/powerpc/kasan.txt @@ -0,0 +1,12 @@ +KASAN is supported on powerpc on 32-bit only. + +32 bit support +============== + +KASAN is supported on both hash and nohash MMUs on 32-bit. + +The shadow area sits at the top of the kernel virtual memory space above the +fixmap area and occupies one eighth of the total kernel virtual memory space. + +Instrumentation of the vmalloc area is optional, unless built with modules, +in which case it is required. -- 2.27.0
