+ arm64-reword-arch_force_max_order-prompt-and-help-text.patch added to mm-unstable branch

+ arm64-reword-arch_force_max_order-prompt-and-help-text.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: arm64: reword ARCH_FORCE_MAX_ORDER prompt and help text
has been added to the -mm mm-unstable branch.  Its filename is
     arm64-reword-arch_force_max_order-prompt-and-help-text.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/arm64-reword-arch_force_max_order-prompt-and-help-text.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Mike Rapoport (IBM)" <rppt@kernel.org>
Subject: arm64: reword ARCH_FORCE_MAX_ORDER prompt and help text
Date: Fri, 24 Mar 2023 08:22:22 +0300

The prompt and help text of ARCH_FORCE_MAX_ORDER are not even close to
describe this configuration option.

Update both to actually describe what this option does.

Link: https://lkml.kernel.org/r/20230324052233.2654090-4-rppt@kernel.org
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: David Miller <davem@davemloft.net>
Cc: Dinh Nguyen <dinguyen@kernel.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: John Paul Adrian Glaubitz <glaubitz@physik.fu-berlin.de>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Rich Felker <dalias@libc.org>
Cc: "Russell King (Oracle)" <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/arm64/Kconfig |   24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

--- a/arch/arm64/Kconfig~arm64-reword-arch_force_max_order-prompt-and-help-text
+++ a/arch/arm64/Kconfig
@@ -1487,24 +1487,24 @@ config XEN
 # 16K |       27          |      14      |       13        |         11         |
 # 64K |       29          |      16      |       13        |         13         |
 config ARCH_FORCE_MAX_ORDER
-	int "Maximum zone order" if EXPERT && (ARM64_4K_PAGES || ARM64_16K_PAGES)
+	int "Order of maximal physically contiguous allocations" if ARM64_4K_PAGES || ARM64_16K_PAGES
 	default "13" if ARM64_64K_PAGES
 	default "11" if ARM64_16K_PAGES
 	default "10"
 	help
-	  The kernel memory allocator divides physically contiguous memory
-	  blocks into "zones", where each zone is a power of two number of
-	  pages.  This option selects the largest power of two that the kernel
-	  keeps in the memory allocator.  If you need to allocate very large
-	  blocks of physically contiguous memory, then you may need to
-	  increase this value.
+	  The kernel page allocator limits the size of maximal physically
+	  contiguous allocations. The limit is called MAX_ORDER and it
+	  defines the maximal power of two of number of pages that can be
+	  allocated as a single contiguous block. This option allows
+	  overriding the default setting when ability to allocate very
+	  large blocks of physically contiguous memory is required.
 
-	  We make sure that we can allocate up to a HugePage size for each configuration.
-	  Hence we have :
-		MAX_ORDER = PMD_SHIFT - PAGE_SHIFT  => PAGE_SHIFT - 3
+	  The maximal size of allocation cannot exceed the size of the
+	  section, so the value of MAX_ORDER should satisfy
 
-	  However for 4K, we choose a higher default value, 10 as opposed to 9, giving us
-	  4M allocations matching the default size used by generic code.
+	    MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
+
+	  Don't change if unsure.
 
 config UNMAP_KERNEL_AT_EL0
 	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
_

Patches currently in -mm which might be from rppt@kernel.org are

loongarch-drop-ranges-for-definition-of-arch_force_max_order.patch
mips-drop-ranges-for-definition-of-arch_force_max_order.patch
mm-move-get_page_from_free_area-to-mm-page_allocc.patch
mips-fix-comment-about-pgtable_init.patch
mm-page_alloc-add-helper-for-checking-if-check_pages_enabled.patch
mm-move-most-of-core-mm-initialization-to-mm-mm_initc.patch
mm-handle-hashdist-initialization-in-mm-mm_initc.patch
mm-page_alloc-rename-page_alloc_init-to-page_alloc_init_cpuhp.patch
init-fold-build_all_zonelists-and-page_alloc_init_cpuhp-to-mm_init.patch
initmm-move-mm_init-to-mm-mm_initc-and-rename-it-to-mm_core_init.patch
mm-call-ptlockpgtable_cache_init-directly-from-mm_core_init.patch
mm-move-init_mem_debugging_and_hardening-to-mm-mm_initc.patch
initmm-fold-late-call-to-page_ext_init-to-page_alloc_init_late.patch
mm-move-mem_init_print_info-to-mm_initc.patch
mm-move-kmem_cache_init-declaration-to-mm-slabh.patch
mm-move-vmalloc_init-declaration-to-mm-internalh.patch
maintainers-extend-memblock-entry-to-include-mm-initialization.patch
arm-reword-arch_force_max_order-prompt-and-help-text.patch
arm64-drop-ranges-in-definition-of-arch_force_max_order.patch
arm64-reword-arch_force_max_order-prompt-and-help-text.patch
csky-drop-arch_force_max_order.patch
ia64-dont-allow-users-to-override-arch_force_max_order.patch
m68k-reword-arch_force_max_order-prompt-and-help-text.patch
nios2-reword-arch_force_max_order-prompt-and-help-text.patch
nios2-drop-ranges-for-definition-of-arch_force_max_order.patch
powerpc-reword-arch_force_max_order-prompt-and-help-text.patch
powerpc-drop-ranges-for-definition-of-arch_force_max_order.patch
sh-reword-arch_force_max_order-prompt-and-help-text.patch
sh-drop-ranges-for-definition-of-arch_force_max_order.patch
sparc-reword-arch_force_max_order-prompt-and-help-text.patch
xtensa-reword-arch_force_max_order-prompt-and-help-text.patch