Re: [PATCH 0/4 v3] Add KFENCE support for LoongArch

[Huacai Chen <chenhuacai@kernel.org>]

Hi, Enze,

I applied this series (with some small modifications) together with KASAN at:
https://github.com/chenhuacai/linux/commits/loongarch-next

Please confirm everything works well for you.

Huacai

On Tue, Aug 1, 2023 at 10:59 AM Enze Li <lienze@kylinos.cn> wrote:
>
> Hi all,
>
> This patchset adds KFENCE support on LoongArch.
>
> To run the testcases, you will need to enable the following options,
>
> -> Kernel hacking
>    [*] Tracers
>        [*] Support for tracing block IO actions (NEW)
>    -> Kernel Testing and Coverage
>       <*> KUnit - Enable support for unit tests
>
> and then,
>
> -> Kernel hacking
>    -> Memory Debugging
>       [*] KFENCE: low-overhead sampling-based memory safety error detector (NEW)
>           <*> KFENCE integration test suite (NEW)
>
> With these options enabled, KFENCE will be tested during kernel startup.
> And normally, you might get the following feedback,
>
> ========================================================
> [   35.326363 ] # kfence: pass:23 fail:0 skip:2 total:25
> [   35.326486 ] # Totals: pass:23 fail:0 skip:2 total:25
> [   35.326621 ] ok 1 kfence
> ========================================================
>
> you might notice that 2 testcases have been skipped.  If you tend to run
> all testcases, please enable CONFIG_INIT_ON_FREE_DEFAULT_ON, you can
> find it here,
>
> -> Security options
>    -> Kernel hardening options
>       -> Memory initialization
>          [*] Enable heap memory zeroing on free by default
>
> and you might get all testcases passed.
> ========================================================
> [   35.531860 ] # kfence: pass:25 fail:0 skip:0 total:25
> [   35.531999 ] # Totals: pass:25 fail:0 skip:0 total:25
> [   35.532135 ] ok 1 kfence
> ========================================================
>
> v3:
>    * Address Huacai's comments.
>    * Fix a bug that Jackie Liu pointed out.
>    * Rewrite arch_stack_walk() with the suggestion of Jinyang He.
>
> v2:
>    * Address Huacai's comments.
>    * Fix typos in commit message.
>
> Thanks,
> Enze
>
> Enze Li (4):
>   KFENCE: Defer the assignment of the local variable addr
>   LoongArch: mm: Add page table mapped mode support
>   LoongArch: Get stack without NMI when providing regs parameter
>   LoongArch: Add KFENCE support
>
>  arch/loongarch/Kconfig               |  1 +
>  arch/loongarch/include/asm/kfence.h  | 66 ++++++++++++++++++++++++++++
>  arch/loongarch/include/asm/page.h    |  8 +++-
>  arch/loongarch/include/asm/pgtable.h | 16 ++++++-
>  arch/loongarch/kernel/stacktrace.c   | 18 ++++----
>  arch/loongarch/mm/fault.c            | 22 ++++++----
>  arch/loongarch/mm/pgtable.c          |  7 +++
>  mm/kfence/core.c                     |  5 ++-
>  8 files changed, 123 insertions(+), 20 deletions(-)
>  create mode 100644 arch/loongarch/include/asm/kfence.h
>
> --
> 2.34.1
>