Re: [PATCH] Revert arm64: drop ranges in definition of ARCH_FORCE_MAX_ORDER

From: Catalin Marinas
Date: Wed May 03 2023 - 06:20:52 EST


On Tue, May 02, 2023 at 06:40:14PM +0100, Catalin Marinas wrote:
> On Tue, May 02, 2023 at 07:15:20PM +0300, Mike Rapoport wrote:
> > On Tue, May 02, 2023 at 03:07:41PM +0100, Catalin Marinas wrote:
> > > On Mon, May 01, 2023 at 04:24:38PM -0500, Justin Forbes wrote:
> > >
> > > Regarding EXPERT, we could drop it and do like the other architectures
> > > but we'll have randconfig occasionally hitting weird values that won't
> > > build (like -1). Not sure EXPERT helps here.
> >
> > AFAIU, randconfig does not randomize int values, it's probably random
> > people that do ;-)
>
> https://lore.kernel.org/r/202303232149.Chh6KhiI-lkp@xxxxxxxxx
>
> with the randconfig here:
>
> https://download.01.org/0day-ci/archive/20230323/202303232149.Chh6KhiI-lkp@xxxxxxxxx/config

You may be right, I can't get my randconfig to set ARCH_FORCE_MAX_ORDER
to anything other than the default. Maybe the kernel test robot has its
own config randomisation (cc'ing lkp@xxxxxxxxx).

If we don't care about about this randconfig, I'm fine do drop EXPERT
from current mainline, together with the 4K/16K pages condition. The
condition only made sense if we kept the ranges in since these were
configurable (no range for 64K).

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index b1201d25a8a4..1867aba83ba3 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1516,7 +1516,7 @@ config XEN
# 16K | 27 | 14 | 13 | 11 |
# 64K | 29 | 16 | 13 | 13 |
config ARCH_FORCE_MAX_ORDER
- int "Order of maximal physically contiguous allocations" if EXPERT && (ARM64_4K_PAGES || ARM64_16K_PAGES)
+ int "Order of maximal physically contiguous allocations"
default "13" if ARM64_64K_PAGES
default "11" if ARM64_16K_PAGES
default "10"

--
Catalin