Re: Breakage in arch/mips/kernel/traps.c for 64bit

[Ralf Baechle <ralf@linux-mips.org>]

On Sun, May 04, 2008 at 01:16:47AM +0900, Atsushi Nemoto wrote:

> Then how about this fix?
> 
> ---------------------------------------------------------------------
> Subject: [PATCH] Fix detection of kernel segment on 64-bit
> 
> Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
> ---
> diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c
> index cb8b0e2..7893bb3 100644
> --- a/arch/mips/kernel/traps.c
> +++ b/arch/mips/kernel/traps.c
> @@ -78,6 +78,19 @@ void (*board_nmi_handler_setup)(void);
>  void (*board_ejtag_handler_setup)(void);
>  void (*board_bind_eic_interrupt)(int irq, int regset);
>  
> +static inline int kernel_unmapped_seg(void *addr)
> +{
> +	unsigned long a = (unsigned long)addr;
> +
> +#ifdef CONFIG_32BIT
> +	/* KSEG0 or KSEG1 */
> +	return (a & 0xc0000000) == KSEG0;

Slightly cleaner:

  return KSEGX(a) == KSEG0;

Unfortunately there is no such macro for the 64-bit segments nor does
the existing KSEGX() work correctly for non-CKSEGx 64-bit addresses.

  Ralf