Re: [PATCH 1/2] powerpc/64: Correct comment on LOAD_HANDLER()

[Nicholas Piggin <npiggin@gmail.com>]

On Tue, 26 Jul 2016 15:29:29 +1000
Michael Ellerman <mpe@ellerman.id.au> wrote:

> The comment for LOAD_HANDLER() was wrong. The part about kdump has not
> been true since 1f6a93e4c35e ("powerpc: Make it possible to move the
> interrupt handlers away from the kernel").
> 
> Describe how it currently works, and combine the two separate comments
> into one.
> 
> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

Reviewed-by: Nick Piggin <npiggin@gmail.com>

> ---
>  arch/powerpc/include/asm/exception-64s.h | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/powerpc/include/asm/exception-64s.h
> b/arch/powerpc/include/asm/exception-64s.h index
> 93ae809fe5ea..4ff3e2f16b5d 100644 ---
> a/arch/powerpc/include/asm/exception-64s.h +++
> b/arch/powerpc/include/asm/exception-64s.h @@ -84,12 +84,12 @@
>  
>  /*
>   * We're short on space and time in the exception prolog, so we can't
> - * use the normal SET_REG_IMMEDIATE macro. Normally we just need the
> - * low halfword of the address, but for Kdump we need the whole low
> - * word.
> + * use the normal LOAD_REG_IMMEDIATE macro to load the address of
> label.
> + * Instead we get the base of the kernel from paca->kernelbase and
> or in the low
> + * part of label. This requires that the label be within 64KB of
> kernelbase, and
> + * that kernelbase be 64K aligned.
>   */
>  #define LOAD_HANDLER(reg,
> label)					\
> -	/* Handlers must be within 64K of kbase, which must be 64k
> aligned */ \ ori	reg,reg,(label)-_stext;	/* virt addr
> of handler ... */ 
>  /* Exception register prefixes */