Re: [PATCH] ARM: memblock limit must be pmd-aligned

Mark Rutland
2017-06-27T17:15:45Z

On Tue, Jun 27, 2017 at 09:57:17AM -0700, Doug Berger wrote:
> On 06/27/2017 03:59 AM, Mark Rutland wrote:
> > On Mon, Jun 26, 2017 at 05:50:03PM -0700, Doug Berger wrote:
> >> On 06/26/2017 04:43 PM, Laura Abbott wrote:
> >>> On 06/26/2017 10:23 AM, Doug Berger wrote:
> >>>> diff --git a/arch/arm/mm/mmu.c b/arch/arm/mm/mmu.c
> >>>> index 31af3cb59a60..2ae4f9c9d757 100644
> >>>> --- a/arch/arm/mm/mmu.c
> >>>> +++ b/arch/arm/mm/mmu.c
> >>>> @@ -1226,7 +1226,7 @@ void __init adjust_lowmem_bounds(void)
> >>>> if (memblock_limit)
> >>>> memblock_limit = round_down(memblock_limit, PMD_SIZE);
> >>>> if (!memblock_limit)
> >>>> - memblock_limit = arm_lowmem_limit;
> >>>> + memblock_limit = round_down(arm_lowmem_limit, PMD_SIZE);
> >>>>
> >
> > Given we're always going to do the rounding, how about we move that out
> > of the existing conditional, i.e. get rid of the first if, and have:
> >
> > if (!memblock_limit)
> > memblock_limit = arm_lowmem_limit;
> >
> > /*
> > * Round the memblock limit down to a pmd size. This
> > * helps to ensure that we will allocate memory from the
> > * last full pmd, which should be mapped.
> > */
> > memblock_limit = round_down(memblock_limit, PMD_SIZE);
> >
> > Thanks,
> > Mark.
> That makes perfect sense to me. I will submit a v2 with this code
> change. Should I add your Signed-off-by since it is your change?

Since you're writing the patch, there's no need.

Feel free to add my Suggested-by if you want, but I'm not too worried
either way.

Thanks,
Mark.