From b3d40a2b6d10c9d0424d2b398bf962fb6adad87e Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Tue, 22 Mar 2022 14:43:20 -0700 Subject: mm: enforce pageblock_order < MAX_ORDER Some places in the kernel don't really expect pageblock_order >= MAX_ORDER, and it looks like this is only possible in corner cases: 1) CONFIG_DEFERRED_STRUCT_PAGE_INIT we'll end up freeing pageblock_order pages via __free_pages_core(), which cannot possibly work. 2) find_zone_movable_pfns_for_nodes() will roundup the ZONE_MOVABLE start PFN to MAX_ORDER_NR_PAGES. Consequently with a bigger pageblock_order, we could have a single pageblock partially managed by two zones. 3) compaction code runs into __fragmentation_index() with order >= MAX_ORDER, when checking WARN_ON_ONCE(order >= MAX_ORDER). [1] 4) mm/page_reporting.c won't be reporting any pages with default page_reporting_order == pageblock_order, as we'll be skipping the reporting loop inside page_reporting_process_zone(). 5) __rmqueue_fallback() will never be able to steal with ALLOC_NOFRAGMENT. pageblock_order >= MAX_ORDER is weird either way: it's a pure optimization for making alloc_contig_range(), as used for allcoation of gigantic pages, a little more reliable to succeed. However, if there is demand for somewhat reliable allocation of gigantic pages, affected setups should be using CMA or boottime allocations instead. So let's make sure that pageblock_order < MAX_ORDER and simplify. [1] https://lkml.kernel.org/r/87r189a2ks.fsf@linux.ibm.com Link: https://lkml.kernel.org/r/20220214174132.219303-3-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Zi Yan Cc: Aneesh Kumar K.V Cc: Benjamin Herrenschmidt Cc: Christoph Hellwig Cc: Frank Rowand Cc: John Garry via iommu Cc: Marek Szyprowski Cc: Michael Ellerman Cc: Michael S. Tsirkin Cc: Minchan Kim Cc: Paul Mackerras Cc: Rob Herring Cc: Robin Murphy Cc: Vlastimil Babka Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/Kconfig | 3 +++ 1 file changed, 3 insertions(+) (limited to 'mm/Kconfig') diff --git a/mm/Kconfig b/mm/Kconfig index 3326ee3903f3..4c91b92e7537 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -262,6 +262,9 @@ 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. + config CONTIG_ALLOC def_bool (MEMORY_ISOLATION && COMPACTION) || CMA -- cgit v1.2.3 From 07431506e8d752ff21c3d5fba0927fe8be4ed18f Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Tue, 22 Mar 2022 14:45:15 -0700 Subject: mm/hugetlb: generalize ARCH_WANT_GENERAL_HUGETLB ARCH_WANT_GENERAL_HUGETLB config has duplicate definitions on platforms that subscribe it. Instead make it a generic config option which can be selected on applicable platforms when required. Link: https://lkml.kernel.org/r/1643718465-4324-1-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Cc: Russell King Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Mike Kravetz Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/arm/Kconfig | 4 +--- arch/riscv/Kconfig | 4 +--- arch/x86/Kconfig | 4 +--- mm/Kconfig | 3 +++ 4 files changed, 6 insertions(+), 9 deletions(-) (limited to 'mm/Kconfig') diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 4c97cb40eebb..ba6ba78a9cb6 100644 --- a/arch/arm/Kconfig +++ b/arch/arm/Kconfig @@ -37,6 +37,7 @@ config ARM select ARCH_USE_CMPXCHG_LOCKREF select ARCH_USE_MEMTEST select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU + select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_IPC_PARSE_VERSION select ARCH_WANT_LD_ORPHAN_WARN select BINFMT_FLAT_ARGVP_ENVP_ON_STACK @@ -1508,9 +1509,6 @@ config HW_PERF_EVENTS def_bool y depends on ARM_PMU -config ARCH_WANT_GENERAL_HUGETLB - def_bool y - config ARM_MODULE_PLTS bool "Use PLTs to allow module memory to spill over into vmalloc area" depends on MODULES diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 5adcbd9b5e88..0804b9a11934 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -40,6 +40,7 @@ config RISCV select ARCH_USE_MEMTEST select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU select ARCH_WANT_FRAME_POINTERS + select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_HUGE_PMD_SHARE if 64BIT select BINFMT_FLAT_NO_DATA_START_OFFSET if !MMU select BUILDTIME_TABLE_SORT if MMU @@ -171,9 +172,6 @@ config ARCH_SPARSEMEM_ENABLE config ARCH_SELECT_MEMORY_MODEL def_bool ARCH_SPARSEMEM_ENABLE -config ARCH_WANT_GENERAL_HUGETLB - def_bool y - config ARCH_SUPPORTS_UPROBES def_bool y diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 9f5bd41bf660..37372cd5c9a7 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -118,6 +118,7 @@ config X86 select ARCH_WANT_DEFAULT_BPF_JIT if X86_64 select ARCH_WANTS_DYNAMIC_TASK_STRUCT select ARCH_WANTS_NO_INSTR + select ARCH_WANT_GENERAL_HUGETLB select ARCH_WANT_HUGE_PMD_SHARE select ARCH_WANT_LD_ORPHAN_WARN select ARCH_WANTS_THP_SWAP if X86_64 @@ -347,9 +348,6 @@ config ARCH_NR_GPIO config ARCH_SUSPEND_POSSIBLE def_bool y -config ARCH_WANT_GENERAL_HUGETLB - def_bool y - config AUDIT_ARCH def_bool y if X86_64 diff --git a/mm/Kconfig b/mm/Kconfig index 4c91b92e7537..1235cec5ceaa 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -414,6 +414,9 @@ choice benefit. endchoice +config ARCH_WANT_GENERAL_HUGETLB + bool + config ARCH_WANTS_THP_SWAP def_bool n -- cgit v1.2.3