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

Ze Gao posted 4 patches 2 years, 8 months ago
There is a newer version of this series
[PATCH v2 4/4] rehook, fprobe: do not trace rethook related functions
Posted by Ze Gao 2 years, 8 months ago 
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>
---
 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
Re: [PATCH v2 4/4] rehook, fprobe: do not trace rethook related functions
Posted by Masami Hiramatsu (Google) 2 years, 8 months ago 
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>
Re: [PATCH v2 4/4] rehook, fprobe: do not trace rethook related functions
Posted by Steven Rostedt 2 years, 8 months ago 
On Tue, 16 May 2023 15:18:30 +0800
Ze Gao <zegao2021@gmail.com> wrote:

>  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

Unrelated to this patch, but someday we need to change the -pg above to
$(CC_FLAGS_FTRACE).

-- Steve


>  endif
>  
>  KASAN_SANITIZE_head$(BITS).o				:= n
> --
Re: [PATCH v2 4/4] rehook, fprobe: do not trace rethook related functions
Posted by Ze Gao 2 years, 8 months ago 
Got it!  Thank you, Steevn.  Maybe I can give it a try later :)

Regards,
Ze

On Tue, May 16, 2023 at 10:20 PM Steven Rostedt <rostedt@goodmis.org> wrote:
>
> On Tue, 16 May 2023 15:18:30 +0800
> Ze Gao <zegao2021@gmail.com> wrote:
>
> >  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
>
> Unrelated to this patch, but someday we need to change the -pg above to
> $(CC_FLAGS_FTRACE).
>
> -- Steve
>
>
> >  endif
> >
> >  KASAN_SANITIZE_head$(BITS).o                         := n
> > --

Patchew 2.1-devel-b67e4c2

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