The quilt patch titled Subject: mm, treewide: redefine MAX_ORDER sanely has been removed from the -mm tree. Its filename was mm-treewide-redefine-max_order-sanely.patch This patch was dropped because it was merged into the mm-stable branch of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm ------------------------------------------------------ From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Subject: mm, treewide: redefine MAX_ORDER sanely Date: Wed, 15 Mar 2023 14:31:33 +0300 MAX_ORDER currently defined as number of orders page allocator supports: user can ask buddy allocator for page order between 0 and MAX_ORDER-1. This definition is counter-intuitive and lead to number of bugs all over the kernel. Change the definition of MAX_ORDER to be inclusive: the range of orders user can ask from buddy allocator is 0..MAX_ORDER now. [kirill@xxxxxxxxxxxxx: fix min() warning] Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box [akpm@xxxxxxxxxxxxxxxxxxxx: fix another min_t warning] [kirill@xxxxxxxxxxxxx: fixups per Zi Yan] Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@xxxxxxxxxxxxxxxxx [akpm@xxxxxxxxxxxxxxxxxxxx: fix underlining in docs] Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@xxxxxxxxx/ Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@xxxxxxxxxxxxxxx Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx> Reviewed-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx> [powerpc] Cc: "Kirill A. Shutemov" <kirill@xxxxxxxxxxxxx> Cc: Zi Yan <ziy@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/admin-guide/kdump/vmcoreinfo.rst | 6 +- Documentation/admin-guide/kernel-parameters.txt | 2 arch/arc/Kconfig | 4 - arch/arm/Kconfig | 9 +-- arch/arm/configs/imx_v6_v7_defconfig | 2 arch/arm/configs/milbeaut_m10v_defconfig | 2 arch/arm/configs/oxnas_v6_defconfig | 2 arch/arm/configs/pxa_defconfig | 2 arch/arm/configs/sama7_defconfig | 2 arch/arm/configs/sp7021_defconfig | 2 arch/arm64/Kconfig | 27 ++++----- arch/arm64/include/asm/sparsemem.h | 2 arch/arm64/kvm/hyp/include/nvhe/gfp.h | 2 arch/arm64/kvm/hyp/nvhe/page_alloc.c | 10 +-- arch/csky/Kconfig | 2 arch/ia64/Kconfig | 8 +- arch/ia64/include/asm/sparsemem.h | 4 - arch/ia64/mm/hugetlbpage.c | 2 arch/loongarch/Kconfig | 15 ++--- arch/m68k/Kconfig.cpu | 5 - arch/mips/Kconfig | 19 ++----- arch/nios2/Kconfig | 7 -- arch/powerpc/Kconfig | 27 ++++----- arch/powerpc/configs/85xx/ge_imp3a_defconfig | 2 arch/powerpc/configs/fsl-emb-nonhw.config | 2 arch/powerpc/mm/book3s64/iommu_api.c | 2 arch/powerpc/mm/hugetlbpage.c | 2 arch/powerpc/platforms/powernv/pci-ioda.c | 2 arch/sh/configs/ecovec24_defconfig | 2 arch/sh/mm/Kconfig | 17 ++---- arch/sparc/Kconfig | 5 - arch/sparc/kernel/pci_sun4v.c | 2 arch/sparc/kernel/traps_64.c | 2 arch/sparc/mm/tsb.c | 4 - arch/um/kernel/um_arch.c | 4 - arch/xtensa/Kconfig | 5 - drivers/base/regmap/regmap-debugfs.c | 8 +- drivers/block/floppy.c | 2 drivers/crypto/ccp/sev-dev.c | 2 drivers/crypto/hisilicon/sgl.c | 6 +- drivers/gpu/drm/i915/gem/i915_gem_internal.c | 2 drivers/gpu/drm/i915/gem/selftests/huge_pages.c | 2 drivers/gpu/drm/ttm/ttm_pool.c | 22 ++++---- drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h | 2 drivers/iommu/dma-iommu.c | 2 drivers/irqchip/irq-gic-v3-its.c | 4 - drivers/md/dm-bufio.c | 2 drivers/misc/genwqe/card_dev.c | 2 drivers/misc/genwqe/card_utils.c | 4 - drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 2 drivers/net/ethernet/ibm/ibmvnic.h | 2 drivers/video/fbdev/hyperv_fb.c | 4 - drivers/video/fbdev/vermilion/vermilion.c | 2 drivers/virtio/virtio_balloon.c | 2 drivers/virtio/virtio_mem.c | 12 ++-- fs/ramfs/file-nommu.c | 2 include/drm/ttm/ttm_pool.h | 2 include/linux/hugetlb.h | 2 include/linux/mmzone.h | 10 +-- include/linux/pageblock-flags.h | 4 - include/linux/slab.h | 6 +- kernel/crash_core.c | 2 kernel/dma/pool.c | 6 +- kernel/events/ring_buffer.c | 6 +- mm/Kconfig | 10 +-- mm/compaction.c | 8 +- mm/debug_vm_pgtable.c | 4 - mm/huge_memory.c | 2 mm/hugetlb.c | 4 - mm/kmsan/init.c | 6 +- mm/memblock.c | 2 mm/memory_hotplug.c | 4 - mm/page_alloc.c | 38 +++++++------- mm/page_isolation.c | 12 ++-- mm/page_owner.c | 6 +- mm/page_reporting.c | 6 +- mm/shuffle.h | 2 mm/slab.c | 2 mm/slub.c | 6 +- mm/vmscan.c | 2 mm/vmstat.c | 14 ++--- net/smc/smc_ib.c | 2 security/integrity/ima/ima_crypto.c | 2 tools/testing/memblock/linux/mmzone.h | 6 +- 84 files changed, 223 insertions(+), 253 deletions(-) --- a/arch/arc/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arc/Kconfig @@ -556,7 +556,7 @@ endmenu # "ARC Architecture Configurati config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "12" if ARC_HUGEPAGE_16M - default "11" + default "11" if ARC_HUGEPAGE_16M + default "10" source "kernel/power/Kconfig" --- a/arch/arm64/include/asm/sparsemem.h~mm-treewide-redefine-max_order-sanely +++ a/arch/arm64/include/asm/sparsemem.h @@ -10,7 +10,7 @@ /* * Section size must be at least 512MB for 64K base * page size config. Otherwise it will be less than - * (MAX_ORDER - 1) and the build process will fail. + * MAX_ORDER and the build process will fail. */ #ifdef CONFIG_ARM64_64K_PAGES #define SECTION_SIZE_BITS 29 --- a/arch/arm64/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm64/Kconfig @@ -1476,22 +1476,22 @@ config XEN # include/linux/mmzone.h requires the following to be true: # -# MAX_ORDER - 1 + PAGE_SHIFT <= SECTION_SIZE_BITS +# MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS # -# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS + 1 - PAGE_SHIFT: +# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT: # # | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_ORDER | default MAX_ORDER | # ----+-------------------+--------------+-----------------+--------------------+ -# 4K | 27 | 12 | 16 | 11 | -# 16K | 27 | 14 | 14 | 12 | -# 64K | 29 | 16 | 14 | 14 | +# 4K | 27 | 12 | 15 | 10 | +# 16K | 27 | 14 | 13 | 11 | +# 64K | 29 | 16 | 13 | 13 | config ARCH_FORCE_MAX_ORDER int "Maximum zone order" if ARM64_4K_PAGES || ARM64_16K_PAGES - default "14" if ARM64_64K_PAGES - range 12 14 if ARM64_16K_PAGES - default "12" if ARM64_16K_PAGES - range 11 16 if ARM64_4K_PAGES - default "11" + 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 blocks into "zones", where each zone is a power of two number of @@ -1500,14 +1500,11 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - We make sure that we can allocate up to a HugePage size for each configuration. Hence we have : - MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2 + MAX_ORDER = PMD_SHIFT - PAGE_SHIFT => PAGE_SHIFT - 3 - However for 4K, we choose a higher default value, 11 as opposed to 10, giving us + 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. config UNMAP_KERNEL_AT_EL0 --- a/arch/arm64/kvm/hyp/include/nvhe/gfp.h~mm-treewide-redefine-max_order-sanely +++ a/arch/arm64/kvm/hyp/include/nvhe/gfp.h @@ -16,7 +16,7 @@ struct hyp_pool { * API at EL2. */ hyp_spinlock_t lock; - struct list_head free_area[MAX_ORDER]; + struct list_head free_area[MAX_ORDER + 1]; phys_addr_t range_start; phys_addr_t range_end; unsigned short max_order; --- a/arch/arm64/kvm/hyp/nvhe/page_alloc.c~mm-treewide-redefine-max_order-sanely +++ a/arch/arm64/kvm/hyp/nvhe/page_alloc.c @@ -110,7 +110,7 @@ static void __hyp_attach_page(struct hyp * after coalescing, so make sure to mark it HYP_NO_ORDER proactively. */ p->order = HYP_NO_ORDER; - for (; (order + 1) < pool->max_order; order++) { + for (; (order + 1) <= pool->max_order; order++) { buddy = __find_buddy_avail(pool, p, order); if (!buddy) break; @@ -203,9 +203,9 @@ void *hyp_alloc_pages(struct hyp_pool *p hyp_spin_lock(&pool->lock); /* Look for a high-enough-order page */ - while (i < pool->max_order && list_empty(&pool->free_area[i])) + while (i <= pool->max_order && list_empty(&pool->free_area[i])) i++; - if (i >= pool->max_order) { + if (i > pool->max_order) { hyp_spin_unlock(&pool->lock); return NULL; } @@ -228,8 +228,8 @@ int hyp_pool_init(struct hyp_pool *pool, int i; hyp_spin_lock_init(&pool->lock); - pool->max_order = min(MAX_ORDER, get_order((nr_pages + 1) << PAGE_SHIFT)); - for (i = 0; i < pool->max_order; i++) + pool->max_order = min(MAX_ORDER, get_order(nr_pages << PAGE_SHIFT)); + for (i = 0; i <= pool->max_order; i++) INIT_LIST_HEAD(&pool->free_area[i]); pool->range_start = phys; pool->range_end = phys + (nr_pages << PAGE_SHIFT); --- a/arch/arm/configs/imx_v6_v7_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/configs/imx_v6_v7_defconfig @@ -31,7 +31,7 @@ CONFIG_SOC_VF610=y CONFIG_SMP=y CONFIG_ARM_PSCI=y CONFIG_HIGHMEM=y -CONFIG_ARCH_FORCE_MAX_ORDER=14 +CONFIG_ARCH_FORCE_MAX_ORDER=13 CONFIG_CMDLINE="noinitrd console=ttymxc0,115200" CONFIG_KEXEC=y CONFIG_CPU_FREQ=y --- a/arch/arm/configs/milbeaut_m10v_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/configs/milbeaut_m10v_defconfig @@ -26,7 +26,7 @@ CONFIG_THUMB2_KERNEL=y # CONFIG_THUMB2_AVOID_R_ARM_THM_JUMP11 is not set # CONFIG_ARM_PATCH_IDIV is not set CONFIG_HIGHMEM=y -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_SECCOMP=y CONFIG_KEXEC=y CONFIG_EFI=y --- a/arch/arm/configs/oxnas_v6_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/configs/oxnas_v6_defconfig @@ -12,7 +12,7 @@ CONFIG_ARCH_OXNAS=y CONFIG_MACH_OX820=y CONFIG_SMP=y CONFIG_NR_CPUS=16 -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_SECCOMP=y CONFIG_ARM_APPENDED_DTB=y CONFIG_ARM_ATAG_DTB_COMPAT=y --- a/arch/arm/configs/pxa_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/configs/pxa_defconfig @@ -20,7 +20,7 @@ CONFIG_PXA_SHARPSL=y CONFIG_MACH_AKITA=y CONFIG_MACH_BORZOI=y CONFIG_AEABI=y -CONFIG_ARCH_FORCE_MAX_ORDER=9 +CONFIG_ARCH_FORCE_MAX_ORDER=8 CONFIG_CMDLINE="root=/dev/ram0 ro" CONFIG_KEXEC=y CONFIG_CPU_FREQ=y --- a/arch/arm/configs/sama7_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/configs/sama7_defconfig @@ -19,7 +19,7 @@ CONFIG_ATMEL_CLOCKSOURCE_TCB=y # CONFIG_CACHE_L2X0 is not set # CONFIG_ARM_PATCH_IDIV is not set # CONFIG_CPU_SW_DOMAIN_PAN is not set -CONFIG_ARCH_FORCE_MAX_ORDER=15 +CONFIG_ARCH_FORCE_MAX_ORDER=14 CONFIG_UACCESS_WITH_MEMCPY=y # CONFIG_ATAGS is not set CONFIG_CMDLINE="console=ttyS0,115200 earlyprintk ignore_loglevel" --- a/arch/arm/configs/sp7021_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/configs/sp7021_defconfig @@ -17,7 +17,7 @@ CONFIG_ARCH_SUNPLUS=y # CONFIG_VDSO is not set CONFIG_SMP=y CONFIG_THUMB2_KERNEL=y -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_VFP=y CONFIG_NEON=y CONFIG_MODULES=y --- a/arch/arm/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/arm/Kconfig @@ -1355,9 +1355,9 @@ config ARM_MODULE_PLTS config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "12" if SOC_AM33XX - default "9" if SA1111 - default "11" + default "11" if SOC_AM33XX + default "8" if SA1111 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -1366,9 +1366,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - config ALIGNMENT_TRAP def_bool CPU_CP15_MMU select HAVE_PROC_CPU if PROC_FS --- a/arch/csky/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/csky/Kconfig @@ -334,7 +334,7 @@ config HIGHMEM config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "11" + default "10" config DRAM_BASE hex "DRAM start addr (the same with memory-section in dts)" --- a/arch/ia64/include/asm/sparsemem.h~mm-treewide-redefine-max_order-sanely +++ a/arch/ia64/include/asm/sparsemem.h @@ -12,9 +12,9 @@ #define SECTION_SIZE_BITS (30) #define MAX_PHYSMEM_BITS (50) #ifdef CONFIG_ARCH_FORCE_MAX_ORDER -#if ((CONFIG_ARCH_FORCE_MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS) +#if (CONFIG_ARCH_FORCE_MAX_ORDER + PAGE_SHIFT > SECTION_SIZE_BITS) #undef SECTION_SIZE_BITS -#define SECTION_SIZE_BITS (CONFIG_ARCH_FORCE_MAX_ORDER - 1 + PAGE_SHIFT) +#define SECTION_SIZE_BITS (CONFIG_ARCH_FORCE_MAX_ORDER + PAGE_SHIFT) #endif #endif --- a/arch/ia64/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/ia64/Kconfig @@ -202,10 +202,10 @@ config IA64_CYCLONE If you're unsure, answer N. config ARCH_FORCE_MAX_ORDER - int "MAX_ORDER (11 - 17)" if !HUGETLB_PAGE - range 11 17 if !HUGETLB_PAGE - default "17" if HUGETLB_PAGE - default "11" + int "MAX_ORDER (10 - 16)" if !HUGETLB_PAGE + range 10 16 if !HUGETLB_PAGE + default "16" if HUGETLB_PAGE + default "10" config SMP bool "Symmetric multi-processing support" --- a/arch/ia64/mm/hugetlbpage.c~mm-treewide-redefine-max_order-sanely +++ a/arch/ia64/mm/hugetlbpage.c @@ -170,7 +170,7 @@ static int __init hugetlb_setup_sz(char size = memparse(str, &str); if (*str || !is_power_of_2(size) || !(tr_pages & size) || size <= PAGE_SIZE || - size >= (1UL << PAGE_SHIFT << MAX_ORDER)) { + size > (1UL << PAGE_SHIFT << MAX_ORDER)) { printk(KERN_WARNING "Invalid huge page size specified\n"); return 1; } --- a/arch/loongarch/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/loongarch/Kconfig @@ -420,12 +420,12 @@ config NODES_SHIFT config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 14 64 if PAGE_SIZE_64KB - default "14" if PAGE_SIZE_64KB - range 12 64 if PAGE_SIZE_16KB - default "12" if PAGE_SIZE_16KB - range 11 64 - default "11" + range 13 63 if PAGE_SIZE_64KB + default "13" if PAGE_SIZE_64KB + range 11 63 if PAGE_SIZE_16KB + default "11" if PAGE_SIZE_16KB + range 10 63 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -434,9 +434,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. --- a/arch/m68k/Kconfig.cpu~mm-treewide-redefine-max_order-sanely +++ a/arch/m68k/Kconfig.cpu @@ -400,7 +400,7 @@ config SINGLE_MEMORY_CHUNK config ARCH_FORCE_MAX_ORDER int "Maximum zone order" if ADVANCED depends on !SINGLE_MEMORY_CHUNK - default "11" + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -413,9 +413,6 @@ config ARCH_FORCE_MAX_ORDER value also defines the minimal size of the hole that allows freeing unused memory map. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - config 060_WRITETHROUGH bool "Use write-through caching for 68060 supervisor accesses" depends on ADVANCED && M68060 --- a/arch/mips/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/mips/Kconfig @@ -2137,14 +2137,14 @@ endchoice config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 14 64 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB - default "14" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB - range 13 64 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB - default "13" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB - range 12 64 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB - default "12" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB - range 0 64 - default "11" + range 13 63 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB + default "13" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_64KB + range 12 63 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB + default "12" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_32KB + range 11 63 if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB + default "11" if MIPS_HUGE_TLB_SUPPORT && PAGE_SIZE_16KB + range 0 63 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -2153,9 +2153,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. --- a/arch/nios2/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/nios2/Kconfig @@ -46,8 +46,8 @@ source "kernel/Kconfig.hz" config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 9 20 - default "11" + range 8 19 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -56,9 +56,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - endmenu source "arch/nios2/platform/Kconfig.platform" --- a/arch/powerpc/configs/85xx/ge_imp3a_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/powerpc/configs/85xx/ge_imp3a_defconfig @@ -30,7 +30,7 @@ CONFIG_PREEMPT=y # CONFIG_CORE_DUMP_DEFAULT_ELF_HEADERS is not set CONFIG_BINFMT_MISC=m CONFIG_MATH_EMULATION=y -CONFIG_ARCH_FORCE_MAX_ORDER=17 +CONFIG_ARCH_FORCE_MAX_ORDER=16 CONFIG_PCI=y CONFIG_PCIEPORTBUS=y CONFIG_PCI_MSI=y --- a/arch/powerpc/configs/fsl-emb-nonhw.config~mm-treewide-redefine-max_order-sanely +++ a/arch/powerpc/configs/fsl-emb-nonhw.config @@ -41,7 +41,7 @@ CONFIG_FIXED_PHY=y CONFIG_FONT_8x16=y CONFIG_FONT_8x8=y CONFIG_FONTS=y -CONFIG_ARCH_FORCE_MAX_ORDER=13 +CONFIG_ARCH_FORCE_MAX_ORDER=12 CONFIG_FRAMEBUFFER_CONSOLE=y CONFIG_FRAME_WARN=1024 CONFIG_FTL=y --- a/arch/powerpc/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/powerpc/Kconfig @@ -897,18 +897,18 @@ config DATA_SHIFT config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 8 9 if PPC64 && PPC_64K_PAGES - default "9" if PPC64 && PPC_64K_PAGES - range 13 13 if PPC64 && !PPC_64K_PAGES - default "13" if PPC64 && !PPC_64K_PAGES - range 9 64 if PPC32 && PPC_16K_PAGES - default "9" if PPC32 && PPC_16K_PAGES - range 7 64 if PPC32 && PPC_64K_PAGES - default "7" if PPC32 && PPC_64K_PAGES - range 5 64 if PPC32 && PPC_256K_PAGES - default "5" if PPC32 && PPC_256K_PAGES - range 11 64 - default "11" + range 7 8 if PPC64 && PPC_64K_PAGES + default "8" if PPC64 && PPC_64K_PAGES + range 12 12 if PPC64 && !PPC_64K_PAGES + default "12" if PPC64 && !PPC_64K_PAGES + range 8 63 if PPC32 && PPC_16K_PAGES + default "8" if PPC32 && PPC_16K_PAGES + range 6 63 if PPC32 && PPC_64K_PAGES + default "6" if PPC32 && PPC_64K_PAGES + range 4 63 if PPC32 && PPC_256K_PAGES + default "4" if PPC32 && PPC_256K_PAGES + range 10 63 + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -917,9 +917,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. For example, on 64-bit systems, 64KB pages can be enabled via CONFIG_PPC_64K_PAGES. Keep this in mind when choosing a value for this option. --- a/arch/powerpc/mm/book3s64/iommu_api.c~mm-treewide-redefine-max_order-sanely +++ a/arch/powerpc/mm/book3s64/iommu_api.c @@ -97,7 +97,7 @@ static long mm_iommu_do_alloc(struct mm_ } mmap_read_lock(mm); - chunk = (1UL << (PAGE_SHIFT + MAX_ORDER - 1)) / + chunk = (1UL << (PAGE_SHIFT + MAX_ORDER)) / sizeof(struct vm_area_struct *); chunk = min(chunk, entries); for (entry = 0; entry < entries; entry += chunk) { --- a/arch/powerpc/mm/hugetlbpage.c~mm-treewide-redefine-max_order-sanely +++ a/arch/powerpc/mm/hugetlbpage.c @@ -615,7 +615,7 @@ void __init gigantic_hugetlb_cma_reserve order = mmu_psize_to_shift(MMU_PAGE_16G) - PAGE_SHIFT; if (order) { - VM_WARN_ON(order < MAX_ORDER); + VM_WARN_ON(order <= MAX_ORDER); hugetlb_cma_reserve(order); } } --- a/arch/powerpc/platforms/powernv/pci-ioda.c~mm-treewide-redefine-max_order-sanely +++ a/arch/powerpc/platforms/powernv/pci-ioda.c @@ -1740,7 +1740,7 @@ static long pnv_pci_ioda2_setup_default_ * DMA window can be larger than available memory, which will * cause errors later. */ - const u64 maxblock = 1UL << (PAGE_SHIFT + MAX_ORDER - 1); + const u64 maxblock = 1UL << (PAGE_SHIFT + MAX_ORDER); /* * We create the default window as big as we can. The constraint is --- a/arch/sh/configs/ecovec24_defconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/sh/configs/ecovec24_defconfig @@ -8,7 +8,7 @@ CONFIG_MODULES=y CONFIG_MODULE_UNLOAD=y # CONFIG_BLK_DEV_BSG is not set CONFIG_CPU_SUBTYPE_SH7724=y -CONFIG_ARCH_FORCE_MAX_ORDER=12 +CONFIG_ARCH_FORCE_MAX_ORDER=11 CONFIG_MEMORY_SIZE=0x10000000 CONFIG_FLATMEM_MANUAL=y CONFIG_SH_ECOVEC=y --- a/arch/sh/mm/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/sh/mm/Kconfig @@ -20,13 +20,13 @@ config PAGE_OFFSET config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - range 9 64 if PAGE_SIZE_16KB - default "9" if PAGE_SIZE_16KB - range 7 64 if PAGE_SIZE_64KB - default "7" if PAGE_SIZE_64KB - range 11 64 - default "14" if !MMU - default "11" + range 8 63 if PAGE_SIZE_16KB + default "8" if PAGE_SIZE_16KB + range 6 63 if PAGE_SIZE_64KB + default "6" if PAGE_SIZE_64KB + range 10 63 + default "13" if !MMU + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -35,9 +35,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - The page size is not necessarily 4KB. Keep this in mind when choosing a value for this option. --- a/arch/sparc/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/sparc/Kconfig @@ -271,7 +271,7 @@ config ARCH_SPARSEMEM_DEFAULT config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "13" + default "12" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -280,9 +280,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 13 means that the largest free memory block is 2^12 pages. - if SPARC64 || COMPILE_TEST source "kernel/power/Kconfig" endif --- a/arch/sparc/kernel/pci_sun4v.c~mm-treewide-redefine-max_order-sanely +++ a/arch/sparc/kernel/pci_sun4v.c @@ -193,7 +193,7 @@ static void *dma_4v_alloc_coherent(struc size = IO_PAGE_ALIGN(size); order = get_order(size); - if (unlikely(order >= MAX_ORDER)) + if (unlikely(order > MAX_ORDER)) return NULL; npages = size >> IO_PAGE_SHIFT; --- a/arch/sparc/kernel/traps_64.c~mm-treewide-redefine-max_order-sanely +++ a/arch/sparc/kernel/traps_64.c @@ -897,7 +897,7 @@ void __init cheetah_ecache_flush_init(vo /* Now allocate error trap reporting scoreboard. */ sz = NR_CPUS * (2 * sizeof(struct cheetah_err_info)); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { if ((PAGE_SIZE << order) >= sz) break; } --- a/arch/sparc/mm/tsb.c~mm-treewide-redefine-max_order-sanely +++ a/arch/sparc/mm/tsb.c @@ -402,8 +402,8 @@ void tsb_grow(struct mm_struct *mm, unsi unsigned long new_rss_limit; gfp_t gfp_flags; - if (max_tsb_size > (PAGE_SIZE << (MAX_ORDER - 1))) - max_tsb_size = (PAGE_SIZE << (MAX_ORDER - 1)); + if (max_tsb_size > PAGE_SIZE << MAX_ORDER) + max_tsb_size = PAGE_SIZE << MAX_ORDER; new_cache_index = 0; for (new_size = 8192; new_size < max_tsb_size; new_size <<= 1UL) { --- a/arch/um/kernel/um_arch.c~mm-treewide-redefine-max_order-sanely +++ a/arch/um/kernel/um_arch.c @@ -368,10 +368,10 @@ int __init linux_main(int argc, char **a max_physmem = TASK_SIZE - uml_physmem - iomem_size - MIN_VMALLOC; /* - * Zones have to begin on a 1 << MAX_ORDER-1 page boundary, + * Zones have to begin on a 1 << MAX_ORDER page boundary, * so this makes sure that's true for highmem */ - max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER - 1)) - 1); + max_physmem &= ~((1 << (PAGE_SHIFT + MAX_ORDER)) - 1); if (physmem_size + iomem_size > max_physmem) { highmem = physmem_size + iomem_size - max_physmem; physmem_size -= highmem; --- a/arch/xtensa/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/arch/xtensa/Kconfig @@ -773,7 +773,7 @@ config HIGHMEM config ARCH_FORCE_MAX_ORDER int "Maximum zone order" - default "11" + default "10" help The kernel memory allocator divides physically contiguous memory blocks into "zones", where each zone is a power of two number of @@ -782,9 +782,6 @@ config ARCH_FORCE_MAX_ORDER blocks of physically contiguous memory, then you may need to increase this value. - This config option is actually maximum order plus one. For example, - a value of 11 means that the largest free memory block is 2^10 pages. - endmenu menu "Power management options" --- a/Documentation/admin-guide/kdump/vmcoreinfo.rst~mm-treewide-redefine-max_order-sanely +++ a/Documentation/admin-guide/kdump/vmcoreinfo.rst @@ -172,7 +172,7 @@ variables. Offset of the free_list's member. This value is used to compute the number of free pages. -Each zone has a free_area structure array called free_area[MAX_ORDER]. +Each zone has a free_area structure array called free_area[MAX_ORDER + 1]. The free_list represents a linked list of free page blocks. (list_head, next|prev) @@ -189,8 +189,8 @@ Offsets of the vmap_area's members. They information. Makedumpfile gets the start address of the vmalloc region from this. -(zone.free_area, MAX_ORDER) ---------------------------- +(zone.free_area, MAX_ORDER + 1) +------------------------------- Free areas descriptor. User-space tools use this value to iterate the free_area ranges. MAX_ORDER is used by the zone buddy allocator. --- a/Documentation/admin-guide/kernel-parameters.txt~mm-treewide-redefine-max_order-sanely +++ a/Documentation/admin-guide/kernel-parameters.txt @@ -3969,7 +3969,7 @@ [KNL] Minimal page reporting order Format: <integer> Adjust the minimal page reporting order. The page - reporting is disabled when it exceeds (MAX_ORDER-1). + reporting is disabled when it exceeds MAX_ORDER. panic= [KNL] Kernel behaviour on panic: delay <timeout> timeout > 0: seconds before rebooting --- a/drivers/base/regmap/regmap-debugfs.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/base/regmap/regmap-debugfs.c @@ -226,8 +226,8 @@ static ssize_t regmap_read_debugfs(struc if (*ppos < 0 || !count) return -EINVAL; - if (count > (PAGE_SIZE << (MAX_ORDER - 1))) - count = PAGE_SIZE << (MAX_ORDER - 1); + if (count > (PAGE_SIZE << MAX_ORDER)) + count = PAGE_SIZE << MAX_ORDER; buf = kmalloc(count, GFP_KERNEL); if (!buf) @@ -373,8 +373,8 @@ static ssize_t regmap_reg_ranges_read_fi if (*ppos < 0 || !count) return -EINVAL; - if (count > (PAGE_SIZE << (MAX_ORDER - 1))) - count = PAGE_SIZE << (MAX_ORDER - 1); + if (count > (PAGE_SIZE << MAX_ORDER)) + count = PAGE_SIZE << MAX_ORDER; buf = kmalloc(count, GFP_KERNEL); if (!buf) --- a/drivers/block/floppy.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/block/floppy.c @@ -3079,7 +3079,7 @@ static void raw_cmd_free(struct floppy_r } } -#define MAX_LEN (1UL << (MAX_ORDER - 1) << PAGE_SHIFT) +#define MAX_LEN (1UL << MAX_ORDER << PAGE_SHIFT) static int raw_cmd_copyin(int cmd, void __user *param, struct floppy_raw_cmd **rcmd) --- a/drivers/crypto/ccp/sev-dev.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/crypto/ccp/sev-dev.c @@ -886,7 +886,7 @@ static int sev_ioctl_do_get_id2(struct s /* * The length of the ID shouldn't be assumed by software since * it may change in the future. The allocation size is limited - * to 1 << (PAGE_SHIFT + MAX_ORDER - 1) by the page allocator. + * to 1 << (PAGE_SHIFT + MAX_ORDER) by the page allocator. * If the allocation fails, simply return ENOMEM rather than * warning in the kernel log. */ --- a/drivers/crypto/hisilicon/sgl.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/crypto/hisilicon/sgl.c @@ -70,11 +70,11 @@ struct hisi_acc_sgl_pool *hisi_acc_creat HISI_ACC_SGL_ALIGN_SIZE); /* - * the pool may allocate a block of memory of size PAGE_SIZE * 2^(MAX_ORDER - 1), + * the pool may allocate a block of memory of size PAGE_SIZE * 2^MAX_ORDER, * block size may exceed 2^31 on ia64, so the max of block size is 2^31 */ - block_size = 1 << (PAGE_SHIFT + MAX_ORDER <= 32 ? - PAGE_SHIFT + MAX_ORDER - 1 : 31); + block_size = 1 << (PAGE_SHIFT + MAX_ORDER < 32 ? + PAGE_SHIFT + MAX_ORDER : 31); sgl_num_per_block = block_size / sgl_size; block_num = count / sgl_num_per_block; remain_sgl = count % sgl_num_per_block; --- a/drivers/gpu/drm/i915/gem/i915_gem_internal.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/gpu/drm/i915/gem/i915_gem_internal.c @@ -36,7 +36,7 @@ static int i915_gem_object_get_pages_int struct sg_table *st; struct scatterlist *sg; unsigned int npages; /* restricted by sg_alloc_table */ - int max_order = MAX_ORDER - 1; + int max_order = MAX_ORDER; unsigned int max_segment; gfp_t gfp; --- a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/gpu/drm/i915/gem/selftests/huge_pages.c @@ -115,7 +115,7 @@ static int get_huge_pages(struct drm_i91 do { struct page *page; - GEM_BUG_ON(order >= MAX_ORDER); + GEM_BUG_ON(order > MAX_ORDER); page = alloc_pages(GFP | __GFP_ZERO, order); if (!page) goto err; --- a/drivers/gpu/drm/ttm/ttm_pool.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/gpu/drm/ttm/ttm_pool.c @@ -65,11 +65,11 @@ module_param(page_pool_size, ulong, 0644 static atomic_long_t allocated_pages; -static struct ttm_pool_type global_write_combined[MAX_ORDER]; -static struct ttm_pool_type global_uncached[MAX_ORDER]; +static struct ttm_pool_type global_write_combined[MAX_ORDER + 1]; +static struct ttm_pool_type global_uncached[MAX_ORDER + 1]; -static struct ttm_pool_type global_dma32_write_combined[MAX_ORDER]; -static struct ttm_pool_type global_dma32_uncached[MAX_ORDER]; +static struct ttm_pool_type global_dma32_write_combined[MAX_ORDER + 1]; +static struct ttm_pool_type global_dma32_uncached[MAX_ORDER + 1]; static spinlock_t shrinker_lock; static struct list_head shrinker_list; @@ -405,7 +405,7 @@ int ttm_pool_alloc(struct ttm_pool *pool else gfp_flags |= GFP_HIGHUSER; - for (order = min_t(unsigned int, MAX_ORDER - 1, __fls(num_pages)); + for (order = min_t(unsigned int, MAX_ORDER, __fls(num_pages)); num_pages; order = min_t(unsigned int, order, __fls(num_pages))) { struct ttm_pool_type *pt; @@ -542,7 +542,7 @@ void ttm_pool_init(struct ttm_pool *pool if (use_dma_alloc) { for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) - for (j = 0; j < MAX_ORDER; ++j) + for (j = 0; j <= MAX_ORDER; ++j) ttm_pool_type_init(&pool->caching[i].orders[j], pool, i, j); } @@ -562,7 +562,7 @@ void ttm_pool_fini(struct ttm_pool *pool if (pool->use_dma_alloc) { for (i = 0; i < TTM_NUM_CACHING_TYPES; ++i) - for (j = 0; j < MAX_ORDER; ++j) + for (j = 0; j <= MAX_ORDER; ++j) ttm_pool_type_fini(&pool->caching[i].orders[j]); } @@ -616,7 +616,7 @@ static void ttm_pool_debugfs_header(stru unsigned int i; seq_puts(m, "\t "); - for (i = 0; i < MAX_ORDER; ++i) + for (i = 0; i <= MAX_ORDER; ++i) seq_printf(m, " ---%2u---", i); seq_puts(m, "\n"); } @@ -627,7 +627,7 @@ static void ttm_pool_debugfs_orders(stru { unsigned int i; - for (i = 0; i < MAX_ORDER; ++i) + for (i = 0; i <= MAX_ORDER; ++i) seq_printf(m, " %8u", ttm_pool_type_count(&pt[i])); seq_puts(m, "\n"); } @@ -736,7 +736,7 @@ int ttm_pool_mgr_init(unsigned long num_ spin_lock_init(&shrinker_lock); INIT_LIST_HEAD(&shrinker_list); - for (i = 0; i < MAX_ORDER; ++i) { + for (i = 0; i <= MAX_ORDER; ++i) { ttm_pool_type_init(&global_write_combined[i], NULL, ttm_write_combined, i); ttm_pool_type_init(&global_uncached[i], NULL, ttm_uncached, i); @@ -769,7 +769,7 @@ void ttm_pool_mgr_fini(void) { unsigned int i; - for (i = 0; i < MAX_ORDER; ++i) { + for (i = 0; i <= MAX_ORDER; ++i) { ttm_pool_type_fini(&global_write_combined[i]); ttm_pool_type_fini(&global_uncached[i]); --- a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h~mm-treewide-redefine-max_order-sanely +++ a/drivers/iommu/arm/arm-smmu-v3/arm-smmu-v3.h @@ -182,7 +182,7 @@ #ifdef CONFIG_CMA_ALIGNMENT #define Q_MAX_SZ_SHIFT (PAGE_SHIFT + CONFIG_CMA_ALIGNMENT) #else -#define Q_MAX_SZ_SHIFT (PAGE_SHIFT + MAX_ORDER - 1) +#define Q_MAX_SZ_SHIFT (PAGE_SHIFT + MAX_ORDER) #endif /* --- a/drivers/iommu/dma-iommu.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/iommu/dma-iommu.c @@ -736,7 +736,7 @@ static struct page **__iommu_dma_alloc_p struct page **pages; unsigned int i = 0, nid = dev_to_node(dev); - order_mask &= GENMASK(MAX_ORDER - 1, 0); + order_mask &= GENMASK(MAX_ORDER, 0); if (!order_mask) return NULL; --- a/drivers/irqchip/irq-gic-v3-its.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/irqchip/irq-gic-v3-its.c @@ -2440,8 +2440,8 @@ static bool its_parse_indirect_baser(str * feature is not supported by hardware. */ new_order = max_t(u32, get_order(esz << ids), new_order); - if (new_order >= MAX_ORDER) { - new_order = MAX_ORDER - 1; + if (new_order > MAX_ORDER) { + new_order = MAX_ORDER; ids = ilog2(PAGE_ORDER_TO_SIZE(new_order) / (int)esz); pr_warn("ITS@%pa: %s Table too large, reduce ids %llu->%u\n", &its->phys_base, its_base_type_string[type], --- a/drivers/md/dm-bufio.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/md/dm-bufio.c @@ -408,7 +408,7 @@ static void __cache_size_refresh(void) * If the allocation may fail we use __get_free_pages. Memory fragmentation * won't have a fatal effect here, but it just causes flushes of some other * buffers and more I/O will be performed. Don't use __get_free_pages if it - * always fails (i.e. order >= MAX_ORDER). + * always fails (i.e. order > MAX_ORDER). * * If the allocation shouldn't fail we use __vmalloc. This is only for the * initial reserve allocation, so there's no risk of wasting all vmalloc --- a/drivers/misc/genwqe/card_dev.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/misc/genwqe/card_dev.c @@ -443,7 +443,7 @@ static int genwqe_mmap(struct file *filp if (vsize == 0) return -EINVAL; - if (get_order(vsize) >= MAX_ORDER) + if (get_order(vsize) > MAX_ORDER) return -ENOMEM; dma_map = kzalloc(sizeof(struct dma_mapping), GFP_KERNEL); --- a/drivers/misc/genwqe/card_utils.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/misc/genwqe/card_utils.c @@ -210,7 +210,7 @@ u32 genwqe_crc32(u8 *buff, size_t len, u void *__genwqe_alloc_consistent(struct genwqe_dev *cd, size_t size, dma_addr_t *dma_handle) { - if (get_order(size) >= MAX_ORDER) + if (get_order(size) > MAX_ORDER) return NULL; return dma_alloc_coherent(&cd->pci_dev->dev, size, dma_handle, @@ -308,7 +308,7 @@ int genwqe_alloc_sync_sgl(struct genwqe_ sgl->write = write; sgl->sgl_size = genwqe_sgl_size(sgl->nr_pages); - if (get_order(sgl->sgl_size) >= MAX_ORDER) { + if (get_order(sgl->sgl_size) > MAX_ORDER) { dev_err(&pci_dev->dev, "[%s] err: too much memory requested!\n", __func__); return ret; --- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c @@ -1041,7 +1041,7 @@ static void hns3_init_tx_spare_buffer(st return; order = get_order(alloc_size); - if (order >= MAX_ORDER) { + if (order > MAX_ORDER) { if (net_ratelimit()) dev_warn(ring_to_dev(ring), "failed to allocate tx spare buffer, exceed to max order\n"); return; --- a/drivers/net/ethernet/ibm/ibmvnic.h~mm-treewide-redefine-max_order-sanely +++ a/drivers/net/ethernet/ibm/ibmvnic.h @@ -75,7 +75,7 @@ * pool for the 4MB. Thus the 16 Rx and Tx queues require 32 * 5 = 160 * plus 16 for the TSO pools for a total of 176 LTB mappings per VNIC. */ -#define IBMVNIC_ONE_LTB_MAX ((u32)((1 << (MAX_ORDER - 1)) * PAGE_SIZE)) +#define IBMVNIC_ONE_LTB_MAX ((u32)((1 << MAX_ORDER) * PAGE_SIZE)) #define IBMVNIC_ONE_LTB_SIZE min((u32)(8 << 20), IBMVNIC_ONE_LTB_MAX) #define IBMVNIC_LTB_SET_SIZE (38 << 20) --- a/drivers/video/fbdev/hyperv_fb.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/video/fbdev/hyperv_fb.c @@ -946,7 +946,7 @@ static phys_addr_t hvfb_get_phymem(struc if (request_size == 0) return -1; - if (order < MAX_ORDER) { + if (order <= MAX_ORDER) { /* Call alloc_pages if the size is less than 2^MAX_ORDER */ page = alloc_pages(GFP_KERNEL | __GFP_ZERO, order); if (!page) @@ -977,7 +977,7 @@ static void hvfb_release_phymem(struct h { unsigned int order = get_order(size); - if (order < MAX_ORDER) + if (order <= MAX_ORDER) __free_pages(pfn_to_page(paddr >> PAGE_SHIFT), order); else dma_free_coherent(&hdev->device, --- a/drivers/video/fbdev/vermilion/vermilion.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/video/fbdev/vermilion/vermilion.c @@ -197,7 +197,7 @@ static int vmlfb_alloc_vram(struct vml_i va = &vinfo->vram[i]; order = 0; - while (requested > (PAGE_SIZE << order) && order < MAX_ORDER) + while (requested > (PAGE_SIZE << order) && order <= MAX_ORDER) order++; err = vmlfb_alloc_vram_area(va, order, 0); --- a/drivers/virtio/virtio_balloon.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/virtio/virtio_balloon.c @@ -33,7 +33,7 @@ #define VIRTIO_BALLOON_FREE_PAGE_ALLOC_FLAG (__GFP_NORETRY | __GFP_NOWARN | \ __GFP_NOMEMALLOC) /* The order of free page blocks to report to host */ -#define VIRTIO_BALLOON_HINT_BLOCK_ORDER (MAX_ORDER - 1) +#define VIRTIO_BALLOON_HINT_BLOCK_ORDER MAX_ORDER /* The size of a free page block in bytes */ #define VIRTIO_BALLOON_HINT_BLOCK_BYTES \ (1 << (VIRTIO_BALLOON_HINT_BLOCK_ORDER + PAGE_SHIFT)) --- a/drivers/virtio/virtio_mem.c~mm-treewide-redefine-max_order-sanely +++ a/drivers/virtio/virtio_mem.c @@ -1120,13 +1120,13 @@ static void virtio_mem_clear_fake_offlin */ static void virtio_mem_fake_online(unsigned long pfn, unsigned long nr_pages) { - unsigned long order = MAX_ORDER - 1; + unsigned long order = MAX_ORDER; unsigned long i; /* * We might get called for ranges that don't cover properly aligned - * MAX_ORDER - 1 pages; however, we can only online properly aligned - * pages with an order of MAX_ORDER - 1 at maximum. + * MAX_ORDER pages; however, we can only online properly aligned + * pages with an order of MAX_ORDER at maximum. */ while (!IS_ALIGNED(pfn | nr_pages, 1 << order)) order--; @@ -1237,9 +1237,9 @@ static void virtio_mem_online_page(struc bool do_online; /* - * We can get called with any order up to MAX_ORDER - 1. If our - * subblock size is smaller than that and we have a mixture of plugged - * and unplugged subblocks within such a page, we have to process in + * We can get called with any order up to MAX_ORDER. If our subblock + * size is smaller than that and we have a mixture of plugged and + * unplugged subblocks within such a page, we have to process in * smaller granularity. In that case we'll adjust the order exactly once * within the loop. */ --- a/fs/ramfs/file-nommu.c~mm-treewide-redefine-max_order-sanely +++ a/fs/ramfs/file-nommu.c @@ -70,7 +70,7 @@ int ramfs_nommu_expand_for_mapping(struc /* make various checks */ order = get_order(newsize); - if (unlikely(order >= MAX_ORDER)) + if (unlikely(order > MAX_ORDER)) return -EFBIG; ret = inode_newsize_ok(inode, newsize); --- a/include/drm/ttm/ttm_pool.h~mm-treewide-redefine-max_order-sanely +++ a/include/drm/ttm/ttm_pool.h @@ -72,7 +72,7 @@ struct ttm_pool { bool use_dma32; struct { - struct ttm_pool_type orders[MAX_ORDER]; + struct ttm_pool_type orders[MAX_ORDER + 1]; } caching[TTM_NUM_CACHING_TYPES]; }; --- a/include/linux/hugetlb.h~mm-treewide-redefine-max_order-sanely +++ a/include/linux/hugetlb.h @@ -818,7 +818,7 @@ static inline unsigned huge_page_shift(s static inline bool hstate_is_gigantic(struct hstate *h) { - return huge_page_order(h) >= MAX_ORDER; + return huge_page_order(h) > MAX_ORDER; } static inline unsigned int pages_per_huge_page(const struct hstate *h) --- a/include/linux/mmzone.h~mm-treewide-redefine-max_order-sanely +++ a/include/linux/mmzone.h @@ -26,11 +26,11 @@ /* Free memory management - zoned buddy allocator. */ #ifndef CONFIG_ARCH_FORCE_MAX_ORDER -#define MAX_ORDER 11 +#define MAX_ORDER 10 #else #define MAX_ORDER CONFIG_ARCH_FORCE_MAX_ORDER #endif -#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1)) +#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER) /* * PAGE_ALLOC_COSTLY_ORDER is the order at which allocations are deemed @@ -93,7 +93,7 @@ static inline bool migratetype_is_mergea } #define for_each_migratetype_order(order, type) \ - for (order = 0; order < MAX_ORDER; order++) \ + for (order = 0; order <= MAX_ORDER; order++) \ for (type = 0; type < MIGRATE_TYPES; type++) extern int page_group_by_mobility_disabled; @@ -922,7 +922,7 @@ struct zone { CACHELINE_PADDING(_pad1_); /* free areas of different sizes */ - struct free_area free_area[MAX_ORDER]; + struct free_area free_area[MAX_ORDER + 1]; /* zone flags, see below */ unsigned long flags; @@ -1745,7 +1745,7 @@ static inline bool movable_only_nodes(no #define SECTION_BLOCKFLAGS_BITS \ ((1UL << (PFN_SECTION_SHIFT - pageblock_order)) * NR_PAGEBLOCK_BITS) -#if (MAX_ORDER - 1 + PAGE_SHIFT) > SECTION_SIZE_BITS +#if (MAX_ORDER + PAGE_SHIFT) > SECTION_SIZE_BITS #error Allocator MAX_ORDER exceeds SECTION_SIZE #endif --- a/include/linux/pageblock-flags.h~mm-treewide-redefine-max_order-sanely +++ a/include/linux/pageblock-flags.h @@ -41,14 +41,14 @@ extern unsigned int pageblock_order; * Huge pages are a constant size, but don't exceed the maximum allocation * granularity. */ -#define pageblock_order min_t(unsigned int, HUGETLB_PAGE_ORDER, MAX_ORDER - 1) +#define pageblock_order min_t(unsigned int, HUGETLB_PAGE_ORDER, MAX_ORDER) #endif /* CONFIG_HUGETLB_PAGE_SIZE_VARIABLE */ #else /* CONFIG_HUGETLB_PAGE */ /* If huge pages are not used, group by MAX_ORDER_NR_PAGES */ -#define pageblock_order (MAX_ORDER-1) +#define pageblock_order MAX_ORDER #endif /* CONFIG_HUGETLB_PAGE */ --- a/include/linux/slab.h~mm-treewide-redefine-max_order-sanely +++ a/include/linux/slab.h @@ -284,7 +284,7 @@ static inline unsigned int arch_slab_min * (PAGE_SIZE*2). Larger requests are passed to the page allocator. */ #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 5 #endif @@ -292,7 +292,7 @@ static inline unsigned int arch_slab_min #ifdef CONFIG_SLUB #define KMALLOC_SHIFT_HIGH (PAGE_SHIFT + 1) -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 3 #endif @@ -305,7 +305,7 @@ static inline unsigned int arch_slab_min * be allocated from the same page. */ #define KMALLOC_SHIFT_HIGH PAGE_SHIFT -#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT - 1) +#define KMALLOC_SHIFT_MAX (MAX_ORDER + PAGE_SHIFT) #ifndef KMALLOC_SHIFT_LOW #define KMALLOC_SHIFT_LOW 3 #endif --- a/kernel/crash_core.c~mm-treewide-redefine-max_order-sanely +++ a/kernel/crash_core.c @@ -474,7 +474,7 @@ static int __init crash_save_vmcoreinfo_ VMCOREINFO_OFFSET(list_head, prev); VMCOREINFO_OFFSET(vmap_area, va_start); VMCOREINFO_OFFSET(vmap_area, list); - VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER); + VMCOREINFO_LENGTH(zone.free_area, MAX_ORDER + 1); log_buf_vmcoreinfo_setup(); VMCOREINFO_LENGTH(free_area.free_list, MIGRATE_TYPES); VMCOREINFO_NUMBER(NR_FREE_PAGES); --- a/kernel/dma/pool.c~mm-treewide-redefine-max_order-sanely +++ a/kernel/dma/pool.c @@ -84,8 +84,8 @@ static int atomic_pool_expand(struct gen void *addr; int ret = -ENOMEM; - /* Cannot allocate larger than MAX_ORDER-1 */ - order = min(get_order(pool_size), MAX_ORDER-1); + /* Cannot allocate larger than MAX_ORDER */ + order = min(get_order(pool_size), MAX_ORDER); do { pool_size = 1 << (PAGE_SHIFT + order); @@ -190,7 +190,7 @@ static int __init dma_atomic_pool_init(v /* * If coherent_pool was not used on the command line, default the pool - * sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER-1. + * sizes to 128KB per 1GB of memory, min 128KB, max MAX_ORDER. */ if (!atomic_pool_size) { unsigned long pages = totalram_pages() / (SZ_1G / SZ_128K); --- a/kernel/events/ring_buffer.c~mm-treewide-redefine-max_order-sanely +++ a/kernel/events/ring_buffer.c @@ -609,8 +609,8 @@ static struct page *rb_alloc_aux_page(in { struct page *page; - if (order >= MAX_ORDER) - order = MAX_ORDER - 1; + if (order > MAX_ORDER) + order = MAX_ORDER; do { page = alloc_pages_node(node, PERF_AUX_GFP, order); @@ -814,7 +814,7 @@ struct perf_buffer *rb_alloc(int nr_page size = sizeof(struct perf_buffer); size += nr_pages * sizeof(void *); - if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER) + if (order_base_2(size) > PAGE_SHIFT+MAX_ORDER) goto fail; node = (cpu == -1) ? cpu : cpu_to_node(cpu); --- a/mm/compaction.c~mm-treewide-redefine-max_order-sanely +++ a/mm/compaction.c @@ -583,7 +583,7 @@ static unsigned long isolate_freepages_b if (PageCompound(page)) { const unsigned int order = compound_order(page); - if (likely(order < MAX_ORDER)) { + if (likely(order <= MAX_ORDER)) { blockpfn += (1UL << order) - 1; cursor += (1UL << order) - 1; } @@ -938,7 +938,7 @@ isolate_migratepages_block(struct compac * a valid page order. Consider only values in the * valid order range to prevent low_pfn overflow. */ - if (freepage_order > 0 && freepage_order < MAX_ORDER) + if (freepage_order > 0 && freepage_order <= MAX_ORDER) low_pfn += (1UL << freepage_order) - 1; continue; } @@ -954,7 +954,7 @@ isolate_migratepages_block(struct compac if (PageCompound(page) && !cc->alloc_contig) { const unsigned int order = compound_order(page); - if (likely(order < MAX_ORDER)) + if (likely(order <= MAX_ORDER)) low_pfn += (1UL << order) - 1; goto isolate_fail; } @@ -2124,7 +2124,7 @@ static enum compact_result __compact_fin /* Direct compactor: Is a suitable page free? */ ret = COMPACT_NO_SUITABLE_PAGE; - for (order = cc->order; order < MAX_ORDER; order++) { + for (order = cc->order; order <= MAX_ORDER; order++) { struct free_area *area = &cc->zone->free_area[order]; bool can_steal; --- a/mm/debug_vm_pgtable.c~mm-treewide-redefine-max_order-sanely +++ a/mm/debug_vm_pgtable.c @@ -1086,7 +1086,7 @@ debug_vm_pgtable_alloc_huge_page(struct struct page *page = NULL; #ifdef CONFIG_CONTIG_ALLOC - if (order >= MAX_ORDER) { + if (order > MAX_ORDER) { page = alloc_contig_pages((1 << order), GFP_KERNEL, first_online_node, NULL); if (page) { @@ -1096,7 +1096,7 @@ debug_vm_pgtable_alloc_huge_page(struct } #endif - if (order < MAX_ORDER) + if (order <= MAX_ORDER) page = alloc_pages(GFP_KERNEL, order); return page; --- a/mm/huge_memory.c~mm-treewide-redefine-max_order-sanely +++ a/mm/huge_memory.c @@ -467,7 +467,7 @@ static int __init hugepage_init(void) /* * hugepages can't be allocated by the buddy allocator */ - MAYBE_BUILD_BUG_ON(HPAGE_PMD_ORDER >= MAX_ORDER); + MAYBE_BUILD_BUG_ON(HPAGE_PMD_ORDER > MAX_ORDER); /* * we use page->mapping and page->index in second tail page * as list_head: assuming THP order >= 2 --- a/mm/hugetlb.c~mm-treewide-redefine-max_order-sanely +++ a/mm/hugetlb.c @@ -2090,7 +2090,7 @@ pgoff_t hugetlb_basepage_index(struct pa pgoff_t index = page_index(page_head); unsigned long compound_idx; - if (compound_order(page_head) >= MAX_ORDER) + if (compound_order(page_head) > MAX_ORDER) compound_idx = page_to_pfn(page) - page_to_pfn(page_head); else compound_idx = page - page_head; @@ -4497,7 +4497,7 @@ static int __init default_hugepagesz_set * The number of default huge pages (for this size) could have been * specified as the first hugetlb parameter: hugepages=X. If so, * then default_hstate_max_huge_pages is set. If the default huge - * page size is gigantic (>= MAX_ORDER), then the pages must be + * page size is gigantic (> MAX_ORDER), then the pages must be * allocated here from bootmem allocator. */ if (default_hstate_max_huge_pages) { --- a/mm/Kconfig~mm-treewide-redefine-max_order-sanely +++ a/mm/Kconfig @@ -346,9 +346,9 @@ config SHUFFLE_PAGE_ALLOCATOR the presence of a memory-side-cache. There are also incidental security benefits as it reduces the predictability of page allocations to compliment SLAB_FREELIST_RANDOM, but the - default granularity of shuffling on the "MAX_ORDER - 1" i.e, - 10th order of pages is selected based on cache utilization - benefits on x86. + default granularity of shuffling on the MAX_ORDER i.e, 10th + order of pages is selected based on cache utilization benefits + on x86. While the randomization improves cache utilization it may negatively impact workloads on platforms without a cache. For @@ -666,8 +666,8 @@ config HUGETLB_PAGE_SIZE_VARIABLE HUGETLB_PAGE_ORDER when there are multiple HugeTLB page sizes available on a platform. - Note that the pageblock_order cannot exceed MAX_ORDER - 1 and will be - clamped down to MAX_ORDER - 1. + Note that the pageblock_order cannot exceed MAX_ORDER and will be + clamped down to MAX_ORDER. config CONTIG_ALLOC def_bool (MEMORY_ISOLATION && COMPACTION) || CMA --- a/mm/kmsan/init.c~mm-treewide-redefine-max_order-sanely +++ a/mm/kmsan/init.c @@ -96,7 +96,7 @@ void __init kmsan_init_shadow(void) struct metadata_page_pair { struct page *shadow, *origin; }; -static struct metadata_page_pair held_back[MAX_ORDER] __initdata; +static struct metadata_page_pair held_back[MAX_ORDER + 1] __initdata; /* * Eager metadata allocation. When the memblock allocator is freeing pages to @@ -211,8 +211,8 @@ static void kmsan_memblock_discard(void) * order=N-1, * - repeat. */ - collect.order = MAX_ORDER - 1; - for (int i = MAX_ORDER - 1; i >= 0; i--) { + collect.order = MAX_ORDER; + for (int i = MAX_ORDER; i >= 0; i--) { if (held_back[i].shadow) smallstack_push(&collect, held_back[i].shadow); if (held_back[i].origin) --- a/mm/memblock.c~mm-treewide-redefine-max_order-sanely +++ a/mm/memblock.c @@ -2043,7 +2043,7 @@ static void __init __free_pages_memory(u int order; while (start < end) { - order = min(MAX_ORDER - 1UL, __ffs(start)); + order = min_t(int, MAX_ORDER, __ffs(start)); while (start + (1UL << order) > end) order--; --- a/mm/memory_hotplug.c~mm-treewide-redefine-max_order-sanely +++ a/mm/memory_hotplug.c @@ -596,7 +596,7 @@ static void online_pages_range(unsigned unsigned long pfn; /* - * Online the pages in MAX_ORDER - 1 aligned chunks. The callback might + * Online the pages in MAX_ORDER aligned chunks. The callback might * decide to not expose all pages to the buddy (e.g., expose them * later). We account all pages as being online and belonging to this * zone ("present"). @@ -605,7 +605,7 @@ static void online_pages_range(unsigned * this and the first chunk to online will be pageblock_nr_pages. */ for (pfn = start_pfn; pfn < end_pfn;) { - int order = min(MAX_ORDER - 1UL, __ffs(pfn)); + int order = min_t(int, MAX_ORDER, __ffs(pfn)); (*online_page_callback)(pfn_to_page(pfn), order); pfn += (1UL << order); --- a/mm/page_alloc.c~mm-treewide-redefine-max_order-sanely +++ a/mm/page_alloc.c @@ -1063,7 +1063,7 @@ buddy_merge_likely(unsigned long pfn, un unsigned long higher_page_pfn; struct page *higher_page; - if (order >= MAX_ORDER - 2) + if (order >= MAX_ORDER - 1) return false; higher_page_pfn = buddy_pfn & pfn; @@ -1118,7 +1118,7 @@ static inline void __free_one_page(struc VM_BUG_ON_PAGE(pfn & ((1 << order) - 1), page); VM_BUG_ON_PAGE(bad_range(zone, page), page); - while (order < MAX_ORDER - 1) { + while (order < MAX_ORDER) { if (compaction_capture(capc, page, order, migratetype)) { __mod_zone_freepage_state(zone, -(1 << order), migratetype); @@ -2499,7 +2499,7 @@ struct page *__rmqueue_smallest(struct z struct page *page; /* Find a page of the appropriate size in the preferred list */ - for (current_order = order; current_order < MAX_ORDER; ++current_order) { + for (current_order = order; current_order <= MAX_ORDER; ++current_order) { area = &(zone->free_area[current_order]); page = get_page_from_free_area(area, migratetype); if (!page) @@ -2871,7 +2871,7 @@ static bool unreserve_highatomic_pageblo continue; spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct free_area *area = &(zone->free_area[order]); page = get_page_from_free_area(area, MIGRATE_HIGHATOMIC); @@ -2955,7 +2955,7 @@ __rmqueue_fallback(struct zone *zone, in * approximates finding the pageblock with the most free pages, which * would be too costly to do exactly. */ - for (current_order = MAX_ORDER - 1; current_order >= min_order; + for (current_order = MAX_ORDER; current_order >= min_order; --current_order) { area = &(zone->free_area[current_order]); fallback_mt = find_suitable_fallback(area, current_order, @@ -2981,7 +2981,7 @@ __rmqueue_fallback(struct zone *zone, in return false; find_smallest: - for (current_order = order; current_order < MAX_ORDER; + for (current_order = order; current_order <= MAX_ORDER; current_order++) { area = &(zone->free_area[current_order]); fallback_mt = find_suitable_fallback(area, current_order, @@ -2994,7 +2994,7 @@ find_smallest: * This should not happen - we already found a suitable fallback * when looking for the largest page. */ - VM_BUG_ON(current_order == MAX_ORDER); + VM_BUG_ON(current_order > MAX_ORDER); do_steal: page = get_page_from_free_area(area, fallback_mt); @@ -3955,7 +3955,7 @@ bool __zone_watermark_ok(struct zone *z, return true; /* For a high-order request, check at least one suitable page is free */ - for (o = order; o < MAX_ORDER; o++) { + for (o = order; o <= MAX_ORDER; o++) { struct free_area *area = &z->free_area[o]; int mt; @@ -5475,7 +5475,7 @@ struct page *__alloc_pages(gfp_t gfp, un * There are several places where we assume that the order value is sane * so bail out early if the request is out of bound. */ - if (WARN_ON_ONCE_GFP(order >= MAX_ORDER, gfp)) + if (WARN_ON_ONCE_GFP(order > MAX_ORDER, gfp)) return NULL; gfp &= gfp_allowed_mask; @@ -6205,8 +6205,8 @@ void __show_free_areas(unsigned int filt for_each_populated_zone(zone) { unsigned int order; - unsigned long nr[MAX_ORDER], flags, total = 0; - unsigned char types[MAX_ORDER]; + unsigned long nr[MAX_ORDER + 1], flags, total = 0; + unsigned char types[MAX_ORDER + 1]; if (zone_idx(zone) > max_zone_idx) continue; @@ -6216,7 +6216,7 @@ void __show_free_areas(unsigned int filt printk(KERN_CONT "%s: ", zone->name); spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct free_area *area = &zone->free_area[order]; int type; @@ -6230,7 +6230,7 @@ void __show_free_areas(unsigned int filt } } spin_unlock_irqrestore(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { printk(KERN_CONT "%lu*%lukB ", nr[order], K(1UL) << order); if (nr[order]) @@ -7581,7 +7581,7 @@ static inline void setup_usemap(struct z /* Initialise the number of pages represented by NR_PAGEBLOCK_BITS */ void __init set_pageblock_order(void) { - unsigned int order = MAX_ORDER - 1; + unsigned int order = MAX_ORDER; /* Check that pageblock_nr_pages has not already been setup */ if (pageblock_order) @@ -9076,7 +9076,7 @@ void *__init alloc_large_system_hash(con else table = memblock_alloc_raw(size, SMP_CACHE_BYTES); - } else if (get_order(size) >= MAX_ORDER || hashdist) { + } else if (get_order(size) > MAX_ORDER || hashdist) { table = vmalloc_huge(size, gfp_flags); virt = true; if (table) @@ -9290,7 +9290,7 @@ int alloc_contig_range(unsigned long sta order = 0; outer_start = start; while (!PageBuddy(pfn_to_page(outer_start))) { - if (++order >= MAX_ORDER) { + if (++order > MAX_ORDER) { outer_start = start; break; } @@ -9540,7 +9540,7 @@ bool is_free_buddy_page(struct page *pag unsigned long pfn = page_to_pfn(page); unsigned int order; - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); if (PageBuddy(page_head) && @@ -9548,7 +9548,7 @@ bool is_free_buddy_page(struct page *pag break; } - return order < MAX_ORDER; + return order <= MAX_ORDER; } EXPORT_SYMBOL(is_free_buddy_page); @@ -9599,7 +9599,7 @@ bool take_page_off_buddy(struct page *pa bool ret = false; spin_lock_irqsave(&zone->lock, flags); - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { struct page *page_head = page - (pfn & ((1 << order) - 1)); int page_order = buddy_order(page_head); --- a/mm/page_isolation.c~mm-treewide-redefine-max_order-sanely +++ a/mm/page_isolation.c @@ -226,7 +226,7 @@ static void unset_migratetype_isolate(st */ if (PageBuddy(page)) { order = buddy_order(page); - if (order >= pageblock_order && order < MAX_ORDER - 1) { + if (order >= pageblock_order && order < MAX_ORDER) { buddy = find_buddy_page_pfn(page, page_to_pfn(page), order, NULL); if (buddy && !is_migrate_isolate_page(buddy)) { @@ -290,11 +290,11 @@ __first_valid_page(unsigned long pfn, un * isolate_single_pageblock() * @migratetype: migrate type to set in error recovery. * - * Free and in-use pages can be as big as MAX_ORDER-1 and contain more than one + * Free and in-use pages can be as big as MAX_ORDER and contain more than one * pageblock. When not all pageblocks within a page are isolated at the same * time, free page accounting can go wrong. For example, in the case of - * MAX_ORDER-1 = pageblock_order + 1, a MAX_ORDER-1 page has two pagelbocks. - * [ MAX_ORDER-1 ] + * MAX_ORDER = pageblock_order + 1, a MAX_ORDER page has two pagelbocks. + * [ MAX_ORDER ] * [ pageblock0 | pageblock1 ] * When either pageblock is isolated, if it is a free page, the page is not * split into separate migratetype lists, which is supposed to; if it is an @@ -451,7 +451,7 @@ static int isolate_single_pageblock(unsi * the free page to the right migratetype list. * * head_pfn is not used here as a hugetlb page order - * can be bigger than MAX_ORDER-1, but after it is + * can be bigger than MAX_ORDER, but after it is * freed, the free page order is not. Use pfn within * the range to find the head of the free page. */ @@ -459,7 +459,7 @@ static int isolate_single_pageblock(unsi outer_pfn = pfn; while (!PageBuddy(pfn_to_page(outer_pfn))) { /* stop if we cannot find the free page */ - if (++order >= MAX_ORDER) + if (++order > MAX_ORDER) goto failed; outer_pfn &= ~0UL << order; } --- a/mm/page_owner.c~mm-treewide-redefine-max_order-sanely +++ a/mm/page_owner.c @@ -315,7 +315,7 @@ void pagetypeinfo_showmixedcount_print(s unsigned long freepage_order; freepage_order = buddy_order_unsafe(page); - if (freepage_order < MAX_ORDER) + if (freepage_order <= MAX_ORDER) pfn += (1UL << freepage_order) - 1; continue; } @@ -549,7 +549,7 @@ read_page_owner(struct file *file, char if (PageBuddy(page)) { unsigned long freepage_order = buddy_order_unsafe(page); - if (freepage_order < MAX_ORDER) + if (freepage_order <= MAX_ORDER) pfn += (1UL << freepage_order) - 1; continue; } @@ -657,7 +657,7 @@ static void init_pages_in_zone(pg_data_t if (PageBuddy(page)) { unsigned long order = buddy_order_unsafe(page); - if (order > 0 && order < MAX_ORDER) + if (order > 0 && order <= MAX_ORDER) pfn += (1UL << order) - 1; continue; } --- a/mm/page_reporting.c~mm-treewide-redefine-max_order-sanely +++ a/mm/page_reporting.c @@ -20,7 +20,7 @@ static int page_order_update_notify(cons * If param is set beyond this limit, order is set to default * pageblock_order value */ - return param_set_uint_minmax(val, kp, 0, MAX_ORDER-1); + return param_set_uint_minmax(val, kp, 0, MAX_ORDER); } static const struct kernel_param_ops page_reporting_param_ops = { @@ -276,7 +276,7 @@ page_reporting_process_zone(struct page_ return err; /* Process each free list starting from lowest order/mt */ - for (order = page_reporting_order; order < MAX_ORDER; order++) { + for (order = page_reporting_order; order <= MAX_ORDER; order++) { for (mt = 0; mt < MIGRATE_TYPES; mt++) { /* We do not pull pages from the isolate free list */ if (is_migrate_isolate(mt)) @@ -370,7 +370,7 @@ int page_reporting_register(struct page_ */ if (page_reporting_order == -1) { - if (prdev->order > 0 && prdev->order < MAX_ORDER) + if (prdev->order > 0 && prdev->order <= MAX_ORDER) page_reporting_order = prdev->order; else page_reporting_order = pageblock_order; --- a/mm/shuffle.h~mm-treewide-redefine-max_order-sanely +++ a/mm/shuffle.h @@ -4,7 +4,7 @@ #define _MM_SHUFFLE_H #include <linux/jump_label.h> -#define SHUFFLE_ORDER (MAX_ORDER-1) +#define SHUFFLE_ORDER MAX_ORDER #ifdef CONFIG_SHUFFLE_PAGE_ALLOCATOR DECLARE_STATIC_KEY_FALSE(page_alloc_shuffle_key); --- a/mm/slab.c~mm-treewide-redefine-max_order-sanely +++ a/mm/slab.c @@ -465,7 +465,7 @@ static int __init slab_max_order_setup(c { get_option(&str, &slab_max_order); slab_max_order = slab_max_order < 0 ? 0 : - min(slab_max_order, MAX_ORDER - 1); + min(slab_max_order, MAX_ORDER); slab_max_order_set = true; return 1; --- a/mm/slub.c~mm-treewide-redefine-max_order-sanely +++ a/mm/slub.c @@ -4171,8 +4171,8 @@ static inline int calculate_order(unsign /* * Doh this slab cannot be placed using slub_max_order. */ - order = calc_slab_order(size, 1, MAX_ORDER - 1, 1); - if (order < MAX_ORDER) + order = calc_slab_order(size, 1, MAX_ORDER, 1); + if (order <= MAX_ORDER) return order; return -ENOSYS; } @@ -4697,7 +4697,7 @@ __setup("slub_min_order=", setup_slub_mi static int __init setup_slub_max_order(char *str) { get_option(&str, (int *)&slub_max_order); - slub_max_order = min(slub_max_order, (unsigned int)MAX_ORDER - 1); + slub_max_order = min_t(unsigned int, slub_max_order, MAX_ORDER); return 1; } --- a/mm/vmscan.c~mm-treewide-redefine-max_order-sanely +++ a/mm/vmscan.c @@ -7002,7 +7002,7 @@ unsigned long try_to_free_pages(struct z * scan_control uses s8 fields for order, priority, and reclaim_idx. * Confirm they are large enough for max values. */ - BUILD_BUG_ON(MAX_ORDER > S8_MAX); + BUILD_BUG_ON(MAX_ORDER >= S8_MAX); BUILD_BUG_ON(DEF_PRIORITY > S8_MAX); BUILD_BUG_ON(MAX_NR_ZONES > S8_MAX); --- a/mm/vmstat.c~mm-treewide-redefine-max_order-sanely +++ a/mm/vmstat.c @@ -1055,7 +1055,7 @@ static void fill_contig_page_info(struct info->free_blocks_total = 0; info->free_blocks_suitable = 0; - for (order = 0; order < MAX_ORDER; order++) { + for (order = 0; order <= MAX_ORDER; order++) { unsigned long blocks; /* @@ -1088,7 +1088,7 @@ static int __fragmentation_index(unsigne { unsigned long requested = 1UL << order; - if (WARN_ON_ONCE(order >= MAX_ORDER)) + if (WARN_ON_ONCE(order > MAX_ORDER)) return 0; if (!info->free_blocks_total) @@ -1462,7 +1462,7 @@ static void frag_show_print(struct seq_f int order; seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) + for (order = 0; order <= MAX_ORDER; ++order) /* * Access to nr_free is lockless as nr_free is used only for * printing purposes. Use data_race to avoid KCSAN warning. @@ -1491,7 +1491,7 @@ static void pagetypeinfo_showfree_print( pgdat->node_id, zone->name, migratetype_names[mtype]); - for (order = 0; order < MAX_ORDER; ++order) { + for (order = 0; order <= MAX_ORDER; ++order) { unsigned long freecount = 0; struct free_area *area; struct list_head *curr; @@ -1531,7 +1531,7 @@ static void pagetypeinfo_showfree(struct /* Print header */ seq_printf(m, "%-43s ", "Free pages count per migrate type at order"); - for (order = 0; order < MAX_ORDER; ++order) + for (order = 0; order <= MAX_ORDER; ++order) seq_printf(m, "%6d ", order); seq_putc(m, '\n'); @@ -2153,7 +2153,7 @@ static void unusable_show_print(struct s seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) { + for (order = 0; order <= MAX_ORDER; ++order) { fill_contig_page_info(zone, order, &info); index = unusable_free_index(order, &info); seq_printf(m, "%d.%03d ", index / 1000, index % 1000); @@ -2205,7 +2205,7 @@ static void extfrag_show_print(struct se seq_printf(m, "Node %d, zone %8s ", pgdat->node_id, zone->name); - for (order = 0; order < MAX_ORDER; ++order) { + for (order = 0; order <= MAX_ORDER; ++order) { fill_contig_page_info(zone, order, &info); index = __fragmentation_index(order, &info); seq_printf(m, "%2d.%03d ", index / 1000, index % 1000); --- a/net/smc/smc_ib.c~mm-treewide-redefine-max_order-sanely +++ a/net/smc/smc_ib.c @@ -843,7 +843,7 @@ long smc_ib_setup_per_ibdev(struct smc_i goto out; /* the calculated number of cq entries fits to mlx5 cq allocation */ cqe_size_order = cache_line_size() == 128 ? 7 : 6; - smc_order = MAX_ORDER - cqe_size_order - 1; + smc_order = MAX_ORDER - cqe_size_order; if (SMC_MAX_CQE + 2 > (0x00000001 << smc_order) * PAGE_SIZE) cqattr.cqe = (0x00000001 << smc_order) * PAGE_SIZE - 2; smcibdev->roce_cq_send = ib_create_cq(smcibdev->ibdev, --- a/security/integrity/ima/ima_crypto.c~mm-treewide-redefine-max_order-sanely +++ a/security/integrity/ima/ima_crypto.c @@ -38,7 +38,7 @@ static int param_set_bufsize(const char size = memparse(val, NULL); order = get_order(size); - if (order >= MAX_ORDER) + if (order > MAX_ORDER) return -EINVAL; ima_maxorder = order; ima_bufsize = PAGE_SIZE << order; --- a/tools/testing/memblock/linux/mmzone.h~mm-treewide-redefine-max_order-sanely +++ a/tools/testing/memblock/linux/mmzone.h @@ -17,10 +17,10 @@ enum zone_type { }; #define MAX_NR_ZONES __MAX_NR_ZONES -#define MAX_ORDER 11 -#define MAX_ORDER_NR_PAGES (1 << (MAX_ORDER - 1)) +#define MAX_ORDER 10 +#define MAX_ORDER_NR_PAGES (1 << MAX_ORDER) -#define pageblock_order (MAX_ORDER - 1) +#define pageblock_order MAX_ORDER #define pageblock_nr_pages BIT(pageblock_order) #define pageblock_align(pfn) ALIGN((pfn), pageblock_nr_pages) #define pageblock_start_pfn(pfn) ALIGN_DOWN((pfn), pageblock_nr_pages) _ Patches currently in -mm which might be from kirill.shutemov@xxxxxxxxxxxxxxx are