Re: [PATCH v2 06/15] ppc/vof: Fix unaligned FDT property access

[Peter Maydell]

On Thu, 27 Jun 2024 at 14:39, Akihiko Odaki <akihiko.odaki@daynix.com> wrote:
>
> FDT properties are aligned by 4 bytes, not 8 bytes.
>
> Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
> ---
>  hw/ppc/vof.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/ppc/vof.c b/hw/ppc/vof.c
> index e3b430a81f4f..b5b6514d79fc 100644
> --- a/hw/ppc/vof.c
> +++ b/hw/ppc/vof.c
> @@ -646,7 +646,7 @@ static void vof_dt_memory_available(void *fdt, GArray 
> *claimed, uint64_t base)
>      mem0_reg = fdt_getprop(fdt, offset, "reg", &proplen);
>      g_assert(mem0_reg && proplen == sizeof(uint32_t) * (ac + sc));
>      if (sc == 2) {
> -        mem0_end = be64_to_cpu(*(uint64_t *)(mem0_reg + sizeof(uint32_t) * 
> ac));
> +        mem0_end = ldq_be_p(mem0_reg + sizeof(uint32_t) * ac);
>      } else {
>          mem0_end = be32_to_cpu(*(uint32_t *)(mem0_reg + sizeof(uint32_t) * 
> ac));
>      }

I did wonder if there was a better way to do what this is doing,
but neither we (in system/device_tree.c) nor libfdt seem to
provide one.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM