From: "Mike Rapoport (IBM)" <rppt@kernel.org>
It is not a good idea to change fundamental parameters of core memory
management. Having predefined ranges suggests that the values within
those ranges are sensible, but one has to *really* understand
implications of changing MAX_ORDER before actually amending it and
ranges don't help here.
Drop ranges in definition of ARCH_FORCE_MAX_ORDER
Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
---
arch/arm64/Kconfig | 2 --
1 file changed, 2 deletions(-)
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index e60baf7859d1..bab6483e4317 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -1489,9 +1489,7 @@ config XEN
config ARCH_FORCE_MAX_ORDER
int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES
default "13" if ARM64_64K_PAGES
- range 11 13 if ARM64_16K_PAGES
default "11" if ARM64_16K_PAGES
- range 10 15 if ARM64_4K_PAGES
default "10"
help
The kernel memory allocator divides physically contiguous memory
--
2.35.1Hi Mike,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on 51551d71edbc998fd8c8afa7312db3d270f5998e]
url: https://github.com/intel-lab-lkp/linux/commits/Mike-Rapoport/arm-reword-ARCH_FORCE_MAX_ORDER-prompt-and-help-text/20230323-172512
base: 51551d71edbc998fd8c8afa7312db3d270f5998e
patch link: https://lore.kernel.org/r/20230323092156.2545741-3-rppt%40kernel.org
patch subject: [PATCH 02/14] arm64: drop ranges in definition of ARCH_FORCE_MAX_ORDER
config: arm64-randconfig-r031-20230322 (https://download.01.org/0day-ci/archive/20230324/202303240155.01y6T6Fj-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 67409911353323ca5edf2049ef0df54132fa1ca7)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# install arm64 cross compiling tool for clang build
# apt-get install binutils-aarch64-linux-gnu
# https://github.com/intel-lab-lkp/linux/commit/0522f943c071abf1610651ea40405b7489c50987
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Mike-Rapoport/arm-reword-ARCH_FORCE_MAX_ORDER-prompt-and-help-text/20230323-172512
git checkout 0522f943c071abf1610651ea40405b7489c50987
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/iommu/ kernel/dma/ mm/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202303240155.01y6T6Fj-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
>> mm/memory.c:5791:37: warning: shift count is negative [-Wshift-count-negative]
if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/compiler.h:48:41: note: expanded from macro 'unlikely'
# define unlikely(x) (__branch_check__(x, 0, __builtin_constant_p(x)))
^
include/linux/compiler.h:33:34: note: expanded from macro '__branch_check__'
______r = __builtin_expect(!!(x), expect); \
^
>> mm/memory.c:5791:37: warning: shift count is negative [-Wshift-count-negative]
if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/compiler.h:48:68: note: expanded from macro 'unlikely'
# define unlikely(x) (__branch_check__(x, 0, __builtin_constant_p(x)))
^
include/linux/compiler.h:35:19: note: expanded from macro '__branch_check__'
expect, is_constant); \
^~~~~~~~~~~
mm/memory.c:5843:37: warning: shift count is negative [-Wshift-count-negative]
if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/compiler.h:48:41: note: expanded from macro 'unlikely'
# define unlikely(x) (__branch_check__(x, 0, __builtin_constant_p(x)))
^
include/linux/compiler.h:33:34: note: expanded from macro '__branch_check__'
______r = __builtin_expect(!!(x), expect); \
^
mm/memory.c:5843:37: warning: shift count is negative [-Wshift-count-negative]
if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/compiler.h:48:68: note: expanded from macro 'unlikely'
# define unlikely(x) (__branch_check__(x, 0, __builtin_constant_p(x)))
^
include/linux/compiler.h:35:19: note: expanded from macro '__branch_check__'
expect, is_constant); \
^~~~~~~~~~~
4 warnings generated.
--
>> drivers/iommu/dma-iommu.c:739:16: error: anonymous bit-field has negative width (-1)
order_mask &= GENMASK(MAX_ORDER, 0);
^
include/linux/bits.h:37:3: note: expanded from macro 'GENMASK'
(GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
^
include/linux/bits.h:23:3: note: expanded from macro 'GENMASK_INPUT_CHECK'
(BUILD_BUG_ON_ZERO(__builtin_choose_expr( \
^
include/linux/build_bug.h:16:53: note: expanded from macro 'BUILD_BUG_ON_ZERO'
#define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
^
>> drivers/iommu/dma-iommu.c:739:16: warning: shift count >= width of type [-Wshift-count-overflow]
order_mask &= GENMASK(MAX_ORDER, 0);
^~~~~~~~~~~~~~~~~~~~~
include/linux/bits.h:37:31: note: expanded from macro 'GENMASK'
(GENMASK_INPUT_CHECK(h, l) + __GENMASK(h, l))
^~~~~~~~~~~~~~~
include/linux/bits.h:35:11: note: expanded from macro '__GENMASK'
(~UL(0) >> (BITS_PER_LONG - 1 - (h))))
^ ~~~~~~~~~~~~~~~~~~~~~~~~~
1 warning and 1 error generated.
--
>> kernel/dma/pool.c:197:39: warning: shift count is negative [-Wshift-count-negative]
pages = min_t(unsigned long, pages, MAX_ORDER_NR_PAGES);
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/minmax.h:126:59: note: expanded from macro 'min_t'
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
^
include/linux/minmax.h:37:12: note: expanded from macro '__careful_cmp'
__cmp(x, y, op), \
^
include/linux/minmax.h:28:34: note: expanded from macro '__cmp'
#define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
^
>> kernel/dma/pool.c:197:39: warning: shift count is negative [-Wshift-count-negative]
pages = min_t(unsigned long, pages, MAX_ORDER_NR_PAGES);
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/minmax.h:126:59: note: expanded from macro 'min_t'
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
^
include/linux/minmax.h:37:12: note: expanded from macro '__careful_cmp'
__cmp(x, y, op), \
^
include/linux/minmax.h:28:46: note: expanded from macro '__cmp'
#define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
^
>> kernel/dma/pool.c:197:39: warning: shift count is negative [-Wshift-count-negative]
pages = min_t(unsigned long, pages, MAX_ORDER_NR_PAGES);
^~~~~~~~~~~~~~~~~~
include/linux/mmzone.h:33:31: note: expanded from macro 'MAX_ORDER_NR_PAGES'
#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
^ ~~~~~~~~~
include/linux/minmax.h:126:59: note: expanded from macro 'min_t'
#define min_t(type, x, y) __careful_cmp((type)(x), (type)(y), <)
^
include/linux/minmax.h:38:17: note: expanded from macro '__careful_cmp'
__cmp_once(x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y), op))
^
include/linux/minmax.h:32:25: note: expanded from macro '__cmp_once'
typeof(y) unique_y = (y); \
^
3 warnings generated.
vim +739 drivers/iommu/dma-iommu.c
0db2e5d18f76a6 Robin Murphy 2015-10-01 732
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 733 static struct page **__iommu_dma_alloc_pages(struct device *dev,
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 734 unsigned int count, unsigned long order_mask, gfp_t gfp)
0db2e5d18f76a6 Robin Murphy 2015-10-01 735 {
0db2e5d18f76a6 Robin Murphy 2015-10-01 736 struct page **pages;
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 737 unsigned int i = 0, nid = dev_to_node(dev);
3b6b7e19e31a81 Robin Murphy 2016-04-13 738
98d56389a5e38b Kirill A. Shutemov 2023-03-15 @739 order_mask &= GENMASK(MAX_ORDER, 0);
3b6b7e19e31a81 Robin Murphy 2016-04-13 740 if (!order_mask)
3b6b7e19e31a81 Robin Murphy 2016-04-13 741 return NULL;
0db2e5d18f76a6 Robin Murphy 2015-10-01 742
ab6f4b001c8c72 Gustavo A. R. Silva 2021-09-28 743 pages = kvcalloc(count, sizeof(*pages), GFP_KERNEL);
0db2e5d18f76a6 Robin Murphy 2015-10-01 744 if (!pages)
0db2e5d18f76a6 Robin Murphy 2015-10-01 745 return NULL;
0db2e5d18f76a6 Robin Murphy 2015-10-01 746
0db2e5d18f76a6 Robin Murphy 2015-10-01 747 /* IOMMU can map any pages, so himem can also be used here */
0db2e5d18f76a6 Robin Murphy 2015-10-01 748 gfp |= __GFP_NOWARN | __GFP_HIGHMEM;
0db2e5d18f76a6 Robin Murphy 2015-10-01 749
0db2e5d18f76a6 Robin Murphy 2015-10-01 750 while (count) {
0db2e5d18f76a6 Robin Murphy 2015-10-01 751 struct page *page = NULL;
3b6b7e19e31a81 Robin Murphy 2016-04-13 752 unsigned int order_size;
0db2e5d18f76a6 Robin Murphy 2015-10-01 753
0db2e5d18f76a6 Robin Murphy 2015-10-01 754 /*
0db2e5d18f76a6 Robin Murphy 2015-10-01 755 * Higher-order allocations are a convenience rather
0db2e5d18f76a6 Robin Murphy 2015-10-01 756 * than a necessity, hence using __GFP_NORETRY until
3b6b7e19e31a81 Robin Murphy 2016-04-13 757 * falling back to minimum-order allocations.
0db2e5d18f76a6 Robin Murphy 2015-10-01 758 */
a706e6e10225fb Kirill A. Shutemov 2023-03-15 759 for (order_mask &= GENMASK(__fls(count), 0);
3b6b7e19e31a81 Robin Murphy 2016-04-13 760 order_mask; order_mask &= ~order_size) {
3b6b7e19e31a81 Robin Murphy 2016-04-13 761 unsigned int order = __fls(order_mask);
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 762 gfp_t alloc_flags = gfp;
3b6b7e19e31a81 Robin Murphy 2016-04-13 763
3b6b7e19e31a81 Robin Murphy 2016-04-13 764 order_size = 1U << order;
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 765 if (order_mask > order_size)
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 766 alloc_flags |= __GFP_NORETRY;
c4b17afb0a4e8d Ganapatrao Kulkarni 2018-11-30 767 page = alloc_pages_node(nid, alloc_flags, order);
0db2e5d18f76a6 Robin Murphy 2015-10-01 768 if (!page)
0db2e5d18f76a6 Robin Murphy 2015-10-01 769 continue;
4604393ca0c6e4 Robin Murphy 2020-09-03 770 if (order)
0db2e5d18f76a6 Robin Murphy 2015-10-01 771 split_page(page, order);
0db2e5d18f76a6 Robin Murphy 2015-10-01 772 break;
0db2e5d18f76a6 Robin Murphy 2015-10-01 773 }
0db2e5d18f76a6 Robin Murphy 2015-10-01 774 if (!page) {
0db2e5d18f76a6 Robin Murphy 2015-10-01 775 __iommu_dma_free_pages(pages, i);
0db2e5d18f76a6 Robin Murphy 2015-10-01 776 return NULL;
0db2e5d18f76a6 Robin Murphy 2015-10-01 777 }
3b6b7e19e31a81 Robin Murphy 2016-04-13 778 count -= order_size;
3b6b7e19e31a81 Robin Murphy 2016-04-13 779 while (order_size--)
0db2e5d18f76a6 Robin Murphy 2015-10-01 780 pages[i++] = page++;
0db2e5d18f76a6 Robin Murphy 2015-10-01 781 }
0db2e5d18f76a6 Robin Murphy 2015-10-01 782 return pages;
0db2e5d18f76a6 Robin Murphy 2015-10-01 783 }
0db2e5d18f76a6 Robin Murphy 2015-10-01 784
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
Hi Mike,
Thank you for the patch! Yet something to improve:
[auto build test ERROR on 51551d71edbc998fd8c8afa7312db3d270f5998e]
url: https://github.com/intel-lab-lkp/linux/commits/Mike-Rapoport/arm-reword-ARCH_FORCE_MAX_ORDER-prompt-and-help-text/20230323-172512
base: 51551d71edbc998fd8c8afa7312db3d270f5998e
patch link: https://lore.kernel.org/r/20230323092156.2545741-3-rppt%40kernel.org
patch subject: [PATCH 02/14] arm64: drop ranges in definition of ARCH_FORCE_MAX_ORDER
config: arm64-randconfig-r022-20230322 (https://download.01.org/0day-ci/archive/20230323/202303232149.Chh6KhiI-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/0522f943c071abf1610651ea40405b7489c50987
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Mike-Rapoport/arm-reword-ARCH_FORCE_MAX_ORDER-prompt-and-help-text/20230323-172512
git checkout 0522f943c071abf1610651ea40405b7489c50987
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm64 olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/base/regmap/ drivers/iommu/ fs/proc/ mm/
If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202303232149.Chh6KhiI-lkp@intel.com/
All error/warnings (new ones prefixed by >>):
In file included from include/linux/kernel.h:25,
from mm/mm_init.c:9:
mm/mm_init.c: In function 'find_zone_movable_pfns_for_nodes':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/math.h:61:25: note: in definition of macro 'roundup'
61 | typeof(y) __y = y; \
| ^
mm/mm_init.c:429:55: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
429 | roundup(required_movablecore, MAX_ORDER_NR_PAGES);
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/math.h:61:25: note: in definition of macro 'roundup'
61 | typeof(y) __y = y; \
| ^
mm/mm_init.c:540:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
540 | roundup(zone_movable_pfn[nid], MAX_ORDER_NR_PAGES);
| ^~~~~~~~~~~~~~~~~~
--
In file included from include/linux/gfp.h:7,
from include/linux/mm.h:7,
from mm/debug.c:10:
mm/debug.c: In function '__dump_page':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
mm/debug.c:70:44: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
70 | if (page < head || (page >= head + MAX_ORDER_NR_PAGES)) {
| ^~~~~~~~~~~~~~~~~~
--
In file included from include/linux/build_bug.h:5,
from include/linux/container_of.h:5,
from include/linux/list.h:5,
from include/linux/smp.h:12,
from include/linux/kernel_stat.h:5,
from mm/memory.c:42:
mm/memory.c: In function 'clear_huge_page':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/compiler.h:78:45: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
| ^
mm/memory.c:5791:44: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
5791 | if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
| ^~~~~~~~~~~~~~~~~~
mm/memory.c: In function 'copy_user_huge_page':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/compiler.h:78:45: note: in definition of macro 'unlikely'
78 | # define unlikely(x) __builtin_expect(!!(x), 0)
| ^
mm/memory.c:5843:44: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
5843 | if (unlikely(pages_per_huge_page > MAX_ORDER_NR_PAGES)) {
| ^~~~~~~~~~~~~~~~~~
--
mm/shuffle.c: In function '__shuffle_zone':
>> mm/shuffle.c:86:35: warning: left shift count is negative [-Wshift-count-negative]
86 | const int order_pages = 1 << order;
| ~~^~~~~~~~
--
In file included from include/vdso/const.h:5,
from include/linux/const.h:4,
from include/linux/list.h:9,
from include/linux/wait.h:7,
from include/linux/wait_bit.h:8,
from include/linux/fs.h:6,
from include/linux/debugfs.h:15,
from mm/page_owner.c:2:
mm/page_owner.c: In function 'pagetypeinfo_showmixedcount_print':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/uapi/linux/const.h:32:50: note: in definition of macro '__ALIGN_KERNEL_MASK'
32 | #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
| ^~~~
include/linux/align.h:8:33: note: in expansion of macro '__ALIGN_KERNEL'
8 | #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
| ^~~~~~~~~~~~~~
mm/page_owner.c:298:31: note: in expansion of macro 'ALIGN'
298 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~
mm/page_owner.c:298:46: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
298 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/uapi/linux/const.h:32:61: note: in definition of macro '__ALIGN_KERNEL_MASK'
32 | #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
| ^~~~
include/linux/align.h:8:33: note: in expansion of macro '__ALIGN_KERNEL'
8 | #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
| ^~~~~~~~~~~~~~
mm/page_owner.c:298:31: note: in expansion of macro 'ALIGN'
298 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~
mm/page_owner.c:298:46: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
298 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~~~~~~~~~~~~~~
In file included from include/linux/gfp.h:7,
from include/linux/xarray.h:15,
from include/linux/list_lru.h:14,
from include/linux/fs.h:13:
mm/page_owner.c: In function 'read_page_owner':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
mm/page_owner.c:526:43: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
526 | while (!pfn_valid(pfn) && (pfn & (MAX_ORDER_NR_PAGES - 1)) != 0)
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
mm/page_owner.c:543:29: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
543 | if ((pfn & (MAX_ORDER_NR_PAGES - 1)) == 0 && !pfn_valid(pfn)) {
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
mm/page_owner.c:544:32: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
544 | pfn += MAX_ORDER_NR_PAGES - 1;
| ^~~~~~~~~~~~~~~~~~
mm/page_owner.c: In function 'init_pages_in_zone':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/uapi/linux/const.h:32:50: note: in definition of macro '__ALIGN_KERNEL_MASK'
32 | #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
| ^~~~
include/linux/align.h:8:33: note: in expansion of macro '__ALIGN_KERNEL'
8 | #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
| ^~~~~~~~~~~~~~
mm/page_owner.c:636:31: note: in expansion of macro 'ALIGN'
636 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~
mm/page_owner.c:636:46: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
636 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/uapi/linux/const.h:32:61: note: in definition of macro '__ALIGN_KERNEL_MASK'
32 | #define __ALIGN_KERNEL_MASK(x, mask) (((x) + (mask)) & ~(mask))
| ^~~~
include/linux/align.h:8:33: note: in expansion of macro '__ALIGN_KERNEL'
8 | #define ALIGN(x, a) __ALIGN_KERNEL((x), (a))
| ^~~~~~~~~~~~~~
mm/page_owner.c:636:31: note: in expansion of macro 'ALIGN'
636 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~
mm/page_owner.c:636:46: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
636 | pfn = ALIGN(pfn + 1, MAX_ORDER_NR_PAGES);
| ^~~~~~~~~~~~~~~~~~
--
In file included from include/linux/kernel.h:26,
from arch/arm64/include/asm/cpufeature.h:22,
from arch/arm64/include/asm/ptrace.h:11,
from arch/arm64/include/asm/irqflags.h:10,
from include/linux/irqflags.h:16,
from include/linux/spinlock.h:59,
from include/linux/mmzone.h:8,
from include/linux/gfp.h:7,
from include/linux/mm.h:7,
from mm/page_isolation.c:6:
mm/page_isolation.c: In function 'isolate_single_pageblock':
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:28:27: note: in definition of macro '__cmp'
28 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:28:27: note: in definition of macro '__cmp'
28 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:28:27: note: in definition of macro '__cmp'
28 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:28:40: note: in definition of macro '__cmp'
28 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:28:40: note: in definition of macro '__cmp'
28 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:28:40: note: in definition of macro '__cmp'
28 | #define __cmp(x, y, op) ((x) op (y) ? (x) : (y))
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:31:39: note: in definition of macro '__cmp_once'
31 | typeof(x) unique_x = (x); \
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:31:39: note: in definition of macro '__cmp_once'
31 | typeof(x) unique_x = (x); \
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
>> include/linux/mmzone.h:33:31: warning: left shift count is negative [-Wshift-count-negative]
33 | #define MAX_ORDER_NR_PAGES (1 << MAX_ORDER)
| ^~
include/linux/minmax.h:31:39: note: in definition of macro '__cmp_once'
31 | typeof(x) unique_x = (x); \
| ^
include/linux/minmax.h:74:25: note: in expansion of macro '__careful_cmp'
74 | #define max(x, y) __careful_cmp(x, y, >)
| ^~~~~~~~~~~~~
mm/page_isolation.c:329:22: note: in expansion of macro 'max'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~
include/uapi/linux/const.h:31:41: note: in expansion of macro '__ALIGN_KERNEL_MASK'
31 | #define __ALIGN_KERNEL(x, a) __ALIGN_KERNEL_MASK(x, (typeof(x))(a) - 1)
| ^~~~~~~~~~~~~~~~~~~
include/linux/align.h:9:33: note: in expansion of macro '__ALIGN_KERNEL'
9 | #define ALIGN_DOWN(x, a) __ALIGN_KERNEL((x) - ((a) - 1), (a))
| ^~~~~~~~~~~~~~
mm/page_isolation.c:329:26: note: in expansion of macro 'ALIGN_DOWN'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~
mm/page_isolation.c:329:56: note: in expansion of macro 'MAX_ORDER_NR_PAGES'
329 | start_pfn = max(ALIGN_DOWN(isolate_pageblock, MAX_ORDER_NR_PAGES),
| ^~~~~~~~~~~~~~~~~~
..
vim +16 include/linux/build_bug.h
bc6245e5efd70c Ian Abbott 2017-07-10 6
bc6245e5efd70c Ian Abbott 2017-07-10 7 #ifdef __CHECKER__
bc6245e5efd70c Ian Abbott 2017-07-10 8 #define BUILD_BUG_ON_ZERO(e) (0)
bc6245e5efd70c Ian Abbott 2017-07-10 9 #else /* __CHECKER__ */
bc6245e5efd70c Ian Abbott 2017-07-10 10 /*
bc6245e5efd70c Ian Abbott 2017-07-10 11 * Force a compilation error if condition is true, but also produce a
8788994376d84d Rikard Falkeborn 2019-12-04 12 * result (of value 0 and type int), so the expression can be used
bc6245e5efd70c Ian Abbott 2017-07-10 13 * e.g. in a structure initializer (or where-ever else comma expressions
bc6245e5efd70c Ian Abbott 2017-07-10 14 * aren't permitted).
bc6245e5efd70c Ian Abbott 2017-07-10 15 */
8788994376d84d Rikard Falkeborn 2019-12-04 @16 #define BUILD_BUG_ON_ZERO(e) ((int)(sizeof(struct { int:(-!!(e)); })))
527edbc18a70e7 Masahiro Yamada 2019-01-03 17 #endif /* __CHECKER__ */
527edbc18a70e7 Masahiro Yamada 2019-01-03 18
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests
On Thu, Mar 23, 2023 at 11:21:44AM +0200, Mike Rapoport wrote: > From: "Mike Rapoport (IBM)" <rppt@kernel.org> > > It is not a good idea to change fundamental parameters of core memory > management. Having predefined ranges suggests that the values within > those ranges are sensible, but one has to *really* understand > implications of changing MAX_ORDER before actually amending it and > ranges don't help here. > > Drop ranges in definition of ARCH_FORCE_MAX_ORDER > > Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> > --- > arch/arm64/Kconfig | 2 -- > 1 file changed, 2 deletions(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index e60baf7859d1..bab6483e4317 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -1489,9 +1489,7 @@ config XEN > config ARCH_FORCE_MAX_ORDER > int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES > default "13" if ARM64_64K_PAGES > - range 11 13 if ARM64_16K_PAGES > default "11" if ARM64_16K_PAGES > - range 10 15 if ARM64_4K_PAGES > default "10" I don't mind rewriting the help text as in the subsequent patch but I'd keep the ranges as a safety measure. It's less wasted time explaining to people why some random max order doesn't work. Alternatively, we can drop the ranges but make this option configurable only if EXPERT. -- Catalin
On Thu, Mar 23, 2023 at 10:15:33AM +0000, Catalin Marinas wrote: > On Thu, Mar 23, 2023 at 11:21:44AM +0200, Mike Rapoport wrote: > > From: "Mike Rapoport (IBM)" <rppt@kernel.org> > > > > It is not a good idea to change fundamental parameters of core memory > > management. Having predefined ranges suggests that the values within > > those ranges are sensible, but one has to *really* understand > > implications of changing MAX_ORDER before actually amending it and > > ranges don't help here. > > > > Drop ranges in definition of ARCH_FORCE_MAX_ORDER > > > > Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> > > --- > > arch/arm64/Kconfig | 2 -- > > 1 file changed, 2 deletions(-) > > > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > > index e60baf7859d1..bab6483e4317 100644 > > --- a/arch/arm64/Kconfig > > +++ b/arch/arm64/Kconfig > > @@ -1489,9 +1489,7 @@ config XEN > > config ARCH_FORCE_MAX_ORDER > > int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES > > default "13" if ARM64_64K_PAGES > > - range 11 13 if ARM64_16K_PAGES > > default "11" if ARM64_16K_PAGES > > - range 10 15 if ARM64_4K_PAGES > > default "10" > > I don't mind rewriting the help text as in the subsequent patch but I'd > keep the ranges as a safety measure. It's less wasted time explaining to > people why some random max order doesn't work. Alternatively, we can > drop the ranges but make this option configurable only if EXPERT. I like the EXPERT alternative more. I'll add it in v2. > -- > Catalin -- Sincerely yours, Mike.
On 23 Mar 2023, at 6:37, Mike Rapoport wrote: > On Thu, Mar 23, 2023 at 10:15:33AM +0000, Catalin Marinas wrote: >> On Thu, Mar 23, 2023 at 11:21:44AM +0200, Mike Rapoport wrote: >>> From: "Mike Rapoport (IBM)" <rppt@kernel.org> >>> >>> It is not a good idea to change fundamental parameters of core memory >>> management. Having predefined ranges suggests that the values within >>> those ranges are sensible, but one has to *really* understand >>> implications of changing MAX_ORDER before actually amending it and >>> ranges don't help here. >>> >>> Drop ranges in definition of ARCH_FORCE_MAX_ORDER >>> >>> Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org> >>> --- >>> arch/arm64/Kconfig | 2 -- >>> 1 file changed, 2 deletions(-) >>> >>> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >>> index e60baf7859d1..bab6483e4317 100644 >>> --- a/arch/arm64/Kconfig >>> +++ b/arch/arm64/Kconfig >>> @@ -1489,9 +1489,7 @@ config XEN >>> config ARCH_FORCE_MAX_ORDER >>> int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES >>> default "13" if ARM64_64K_PAGES >>> - range 11 13 if ARM64_16K_PAGES >>> default "11" if ARM64_16K_PAGES >>> - range 10 15 if ARM64_4K_PAGES >>> default "10" >> >> I don't mind rewriting the help text as in the subsequent patch but I'd >> keep the ranges as a safety measure. It's less wasted time explaining to >> people why some random max order doesn't work. Alternatively, we can >> drop the ranges but make this option configurable only if EXPERT. > > I like the EXPERT alternative more. I'll add it in v2. I got an error report from kernel test robot, which set -1 to ARCH_FORCE_MAX_ORDER via random config generator[1]. Does the EXPERT option prevent kernel test robot from generating such config? Or we should fix random config generator? [1] https://lore.kernel.org/linux-mm/91E887E4-0867-421F-9C75-FB9CFF15C33A@nvidia.com/ -- Best Regards, Yan, Zi
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