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Subject: Re: [PATCH] Ftrace : fix function_graph tracer OOPS
From: Steven Rostedt <rostedt@goodmis.org>
To: Sachin Sant <sachinp@in.ibm.com>
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Date: Tue, 13 Oct 2009 23:01:24 -0400
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On Thu, 2009-10-08 at 20:21 +0530, Sachin Sant wrote:
> Switch to LOAD_REG_ADDR().
> 
> Signed-off-by : Sachin Sant <sachinp@in.ibm.com>
> ---
> diff -Naurp old/arch/powerpc/kernel/entry_64.S
> new/arch/powerpc/kernel/entry_64.S
> --- old/arch/powerpc/kernel/entry_64.S  2009-10-08 18:37:44.000000000
> +0530
> +++ new/arch/powerpc/kernel/entry_64.S  2009-10-08 18:34:33.000000000
> +0530
> @@ -1038,8 +1038,8 @@ _GLOBAL(mod_return_to_handler)
>          * We are in a module using the module's TOC.
>          * Switch to our TOC to run inside the core kernel.
>          */
> -       LOAD_REG_IMMEDIATE(r4,ftrace_return_to_handler)
> -       ld      r2, 8(r4)
> +       ld      r2, PACATOC(r13)
> +       LOAD_REG_ADDR(r4,ftrace_return_to_handler)

Actually, the loading of this register is not needed. The original used
the loading to get the r2.

I actually wrote a fix for this a month ago. I never sent it out because
I was distracted by other issues.

I'll send out the two patches I had now.

Could yo test them?

Thanks!

-- Steve

>  
>         bl      .ftrace_return_to_handler
>         nop
>