Re: [PATCH v2 4/4] rehook, fprobe: do not trace rethook related functions

Masami Hiramatsu
2023-05-16T16:05:31Z

On Tue, 16 May 2023 15:18:30 +0800
Ze Gao <zegao2021@gmail.com> wrote:

> These functions are already marked as NOKPROBE to prevent recursion and
> we have the same reason to blacklist them if rethook is used with fprobe,
> since they are beyond the recursion-free region ftrace can guard.
>
> Signed-off-by: Ze Gao <zegao@tencent.com>

Looks good to me.

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thank you!

> ---
> arch/riscv/kernel/probes/Makefile | 2 ++
> arch/s390/kernel/Makefile | 1 +
> arch/x86/kernel/Makefile | 1 +
> 3 files changed, 4 insertions(+)
>
> diff --git a/arch/riscv/kernel/probes/Makefile b/arch/riscv/kernel/probes/Makefile
> index c40139e9ca47..8265ff497977 100644
> --- a/arch/riscv/kernel/probes/Makefile
> +++ b/arch/riscv/kernel/probes/Makefile
> @@ -4,3 +4,5 @@ obj-$(CONFIG_RETHOOK) += rethook.o rethook_trampoline.o
> obj-$(CONFIG_KPROBES_ON_FTRACE) += ftrace.o
> obj-$(CONFIG_UPROBES) += uprobes.o decode-insn.o simulate-insn.o
> CFLAGS_REMOVE_simulate-insn.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_rethook.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_rethook_trampoline.o = $(CC_FLAGS_FTRACE)
> diff --git a/arch/s390/kernel/Makefile b/arch/s390/kernel/Makefile
> index 8983837b3565..6b2a051e1f8a 100644
> --- a/arch/s390/kernel/Makefile
> +++ b/arch/s390/kernel/Makefile
> @@ -10,6 +10,7 @@ CFLAGS_REMOVE_ftrace.o = $(CC_FLAGS_FTRACE)
>
> # Do not trace early setup code
> CFLAGS_REMOVE_early.o = $(CC_FLAGS_FTRACE)
> +CFLAGS_REMOVE_rethook.o = $(CC_FLAGS_FTRACE)
>
> endif
>
> diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
> index dd61752f4c96..4070a01c11b7 100644
> --- a/arch/x86/kernel/Makefile
> +++ b/arch/x86/kernel/Makefile
> @@ -17,6 +17,7 @@ CFLAGS_REMOVE_ftrace.o = -pg
> CFLAGS_REMOVE_early_printk.o = -pg
> CFLAGS_REMOVE_head64.o = -pg
> CFLAGS_REMOVE_sev.o = -pg
> +CFLAGS_REMOVE_rethook.o = -pg
> endif
>
> KASAN_SANITIZE_head$(BITS).o := n
> --
> 2.40.1
>

--
Masami Hiramatsu (Google) <mhiramat@kernel.org>