[PATCH] ARM: vector_table: Fix creation of second level page table

Andrey Smirnov andrew.smirnov at gmail.com
Wed Aug 24 09:07:22 PDT 2016


On Wed, Aug 24, 2016 at 5:23 AM, Sascha Hauer <s.hauer at pengutronix.de> wrote:
> The second level page tables can only start at a 1MiB section boundary,
> so instead of calling arm_create_pte() with the high vector address
> (which is 0xffff0000, not 1MiB aligned) we have to call it with
> 0xfff00000 to correctly create a second level page table. The vectors
> themselves worked as expected with the old value, but the memory around
> it did not do a 1:1 mapping anymore. This breaks SoCs which have
> peripherals in that area, for example Atmel SoCs like the AT91RM9200.
>

Would you mind re-wording it as something to the effect of: "...
mapping anymore, breaking SoCs which also have peripherals in that
area..."? The original sentence structure, to me, reads as if this
patch/commit introduces a change that breaks Atmel SoCs.

> Fixes: f6b77fe9: ARM: Rework vector table setup
>
> Reported-by: Peter Kardos <kardos.peter.sk at gmail.com>
> Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
> ---
>  arch/arm/cpu/mmu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/arm/cpu/mmu.c b/arch/arm/cpu/mmu.c
> index a31bce4..2b70866 100644
> --- a/arch/arm/cpu/mmu.c
> +++ b/arch/arm/cpu/mmu.c
> @@ -307,7 +307,7 @@ static void create_vector_table(unsigned long adr)
>                 vectors = xmemalign(PAGE_SIZE, PAGE_SIZE);
>                 pr_debug("Creating vector table, virt = 0x%p, phys = 0x%08lx\n",
>                          vectors, adr);
> -               exc = arm_create_pte(adr);
> +               exc = arm_create_pte(adr & ~(SZ_1M - 1));

ALIGN_DOWN(adr, SZ_1M) ?

Thanks,
Andrey Smirnov



More information about the barebox mailing list