diff options
Diffstat (limited to 'mm/Kconfig')
| -rw-r--r-- | mm/Kconfig | 168 |
1 files changed, 104 insertions, 64 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index ebd8ea353687..604c58199acb 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -125,8 +125,6 @@ config ZSWAP_COMPRESSOR_DEFAULT config ZSMALLOC tristate -if ZSMALLOC - menu "Zsmalloc allocator options" depends on ZSMALLOC @@ -161,8 +159,6 @@ config ZSMALLOC_CHAIN_SIZE endmenu -endif - menu "Slab allocator options" config SLUB @@ -172,6 +168,7 @@ config SLUB config KVFREE_RCU_BATCHED def_bool y depends on !SLUB_TINY && !TINY_RCU + depends on !RCU_STRICT_GRACE_PERIOD config SLUB_TINY bool "Configure for minimal memory footprint" @@ -247,22 +244,75 @@ config SLUB_STATS out which slabs are relevant to a particular load. Try running: slabinfo -DA -config RANDOM_KMALLOC_CACHES - default n +config KMALLOC_PARTITION_CACHES depends on !SLUB_TINY - bool "Randomize slab caches for normal kmalloc" + bool "Partitioned slab caches for normal kmalloc" + default RANDOM_KMALLOC_CACHES help - A hardening feature that creates multiple copies of slab caches for - normal kmalloc allocation and makes kmalloc randomly pick one based - on code address, which makes the attackers more difficult to spray - vulnerable memory objects on the heap for the purpose of exploiting - memory vulnerabilities. + A hardening feature that creates multiple isolated copies of slab + caches for normal kmalloc allocations. This makes it more difficult + to exploit memory-safety vulnerabilities by attacking vulnerable + co-located memory objects. Several modes are provided. Currently the number of copies is set to 16, a reasonably large value that effectively diverges the memory objects allocated for different subsystems or modules into different caches, at the expense of a - limited degree of memory and CPU overhead that relates to hardware and - system workload. + limited degree of memory and CPU overhead that relates to hardware + and system workload. + +choice + prompt "Partitioned slab cache mode" + depends on KMALLOC_PARTITION_CACHES + default KMALLOC_PARTITION_TYPED if CC_HAS_ALLOC_TOKEN + default KMALLOC_PARTITION_RANDOM + help + Selects the slab cache partitioning mode. + +config KMALLOC_PARTITION_RANDOM + bool "Randomize slab caches for normal kmalloc" + help + Randomly pick a slab cache based on code address and a per-boot + random seed. + + This makes it harder for attackers to predict object co-location. + The placement is random: while attackers don't know which kmalloc + cache an object will be allocated from, they might circumvent + the randomization by retrying attacks across multiple machines until + the target objects are co-located. + +config KMALLOC_PARTITION_TYPED + bool "Type based slab cache selection for normal kmalloc" + depends on CC_HAS_ALLOC_TOKEN + help + Rely on Clang's allocation tokens to choose a slab cache, where token + IDs are derived from the allocated type. + + Unlike KMALLOC_PARTITION_RANDOM, cache assignment is deterministic based + on type, which guarantees that objects of certain types are not + placed in the same cache. This effectively mitigates certain classes + of exploits that probabilistic defenses like KMALLOC_PARTITION_RANDOM + only make harder but not impossible. However, this also means the + cache assignment is predictable. + + Clang's default token ID calculation returns a bounded hash with + disjoint ranges for pointer-containing and pointerless objects: when + used as the slab cache index, this prevents buffer overflows on + primitive buffers from directly corrupting pointer-containing + objects. + + The current effectiveness of Clang's type inference can be judged by + -Rpass=alloc-token, which provides diagnostics where (after dead-code + elimination) type inference failed. + + Requires Clang 22 or later. + +endchoice + +config RANDOM_KMALLOC_CACHES + bool + transitional + help + Transitional config for migration to KMALLOC_PARTITION_CACHES. endmenu # Slab allocator options @@ -340,6 +390,7 @@ choice config FLATMEM_MANUAL bool "Flat Memory" + depends on !NUMA depends on !ARCH_SPARSEMEM_ENABLE || ARCH_FLATMEM_ENABLE help This option is best suited for non-NUMA systems with @@ -374,6 +425,7 @@ config SPARSEMEM config FLATMEM def_bool y + depends on !NUMA depends on !SPARSEMEM || FLATMEM_MANUAL # @@ -455,24 +507,14 @@ config EXCLUSIVE_SYSTEM_RAM def_bool y depends on !DEVMEM || STRICT_DEVMEM -# -# Only be set on architectures that have completely implemented memory hotplug -# feature. If you are not sure, don't touch it. -# -config HAVE_BOOTMEM_INFO_NODE - def_bool n - config ARCH_ENABLE_MEMORY_HOTPLUG bool -config ARCH_ENABLE_MEMORY_HOTREMOVE - bool - # eventually, we can have this option just 'select SPARSEMEM' menuconfig MEMORY_HOTPLUG bool "Memory hotplug" select MEMORY_ISOLATION - depends on SPARSEMEM + depends on SPARSEMEM_VMEMMAP depends on ARCH_ENABLE_MEMORY_HOTPLUG depends on 64BIT select NUMA_KEEP_MEMINFO if NUMA @@ -539,13 +581,10 @@ endchoice config MEMORY_HOTREMOVE bool "Allow for memory hot remove" - select HAVE_BOOTMEM_INFO_NODE if (X86_64 || PPC64) - depends on MEMORY_HOTPLUG && ARCH_ENABLE_MEMORY_HOTREMOVE - depends on MIGRATION + select MIGRATION config MHP_MEMMAP_ON_MEMORY def_bool y - depends on MEMORY_HOTPLUG && SPARSEMEM_VMEMMAP depends on ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE endif # MEMORY_HOTPLUG @@ -572,6 +611,7 @@ config SPLIT_PTE_PTLOCKS depends on !ARM || CPU_CACHE_VIPT depends on !PARISC || PA20 depends on !SPARC32 + depends on !UML config ARCH_ENABLE_SPLIT_PMD_PTLOCK bool @@ -630,20 +670,20 @@ config PAGE_REPORTING those pages to another entity, such as a hypervisor, so that the memory can be freed within the host for other uses. -# -# support for page migration -# -config MIGRATION - bool "Page migration" +config NUMA_MIGRATION + bool "NUMA page migration" default y - depends on (NUMA || ARCH_ENABLE_MEMORY_HOTREMOVE || COMPACTION || CMA) && MMU + depends on NUMA && MMU + select MIGRATION help - Allows the migration of the physical location of pages of processes - while the virtual addresses are not changed. This is useful in - two situations. The first is on NUMA systems to put pages nearer - to the processors accessing. The second is when allocating huge - pages as migration can relocate pages to satisfy a huge page - allocation instead of reclaiming. + Support the migration of pages to other NUMA nodes, available to + user space through interfaces like migrate_pages(), move_pages(), + and mbind(). Selecting this option also enables support for page + demotion for memory tiering. + +config MIGRATION + bool + depends on MMU config DEVICE_MIGRATION def_bool MIGRATION && ZONE_DEVICE @@ -651,7 +691,7 @@ config DEVICE_MIGRATION config ARCH_ENABLE_HUGEPAGE_MIGRATION bool -config ARCH_ENABLE_THP_MIGRATION +config ARCH_HAS_PMD_SOFTLEAVES bool config HUGETLB_PAGE_SIZE_VARIABLE @@ -727,6 +767,7 @@ config MEMORY_FAILURE depends on ARCH_SUPPORTS_MEMORY_FAILURE bool "Enable recovery from hardware memory errors" select INTERVAL_TREE + select MIGRATION help Enables code to recover from some memory failures on systems with MCA recovery. This allows a system to continue running @@ -811,7 +852,6 @@ if TRANSPARENT_HUGEPAGE choice prompt "Transparent Hugepage Support sysfs defaults" - depends on TRANSPARENT_HUGEPAGE default TRANSPARENT_HUGEPAGE_ALWAYS help Selects the sysfs defaults for Transparent Hugepage Support. @@ -841,7 +881,6 @@ endchoice choice prompt "Shmem hugepage allocation defaults" - depends on TRANSPARENT_HUGEPAGE default TRANSPARENT_HUGEPAGE_SHMEM_HUGE_NEVER help Selects the hugepage allocation policy defaults for @@ -887,7 +926,6 @@ endchoice choice prompt "Tmpfs hugepage allocation defaults" - depends on TRANSPARENT_HUGEPAGE default TRANSPARENT_HUGEPAGE_TMPFS_HUGE_NEVER help Selects the hugepage allocation policy defaults for @@ -932,7 +970,7 @@ endchoice config THP_SWAP def_bool y - depends on TRANSPARENT_HUGEPAGE && ARCH_WANTS_THP_SWAP && SWAP && 64BIT + depends on ARCH_WANTS_THP_SWAP && SWAP && 64BIT help Swap transparent huge pages in one piece, without splitting. XXX: For now, swap cluster backing transparent huge page @@ -940,17 +978,6 @@ config THP_SWAP For selection by architectures with reasonable THP sizes. -config READ_ONLY_THP_FOR_FS - bool "Read-only THP for filesystems (EXPERIMENTAL)" - depends on TRANSPARENT_HUGEPAGE - - help - Allow khugepaged to put read-only file-backed pages in THP. - - This is marked experimental because it is a new feature. Write - support of file THPs will be developed in the next few release - cycles. - config NO_PAGE_MAPCOUNT bool "No per-page mapcount (EXPERIMENTAL)" help @@ -1197,9 +1224,7 @@ config ZONE_DMA32 config ZONE_DEVICE bool "Device memory (pmem, HMM, etc...) hotplug support" - depends on MEMORY_HOTPLUG depends on MEMORY_HOTREMOVE - depends on SPARSEMEM_VMEMMAP select XARRAY_MULTI help @@ -1222,6 +1247,7 @@ config ZONE_DEVICE config HMM_MIRROR bool depends on MMU + select MMU_NOTIFIER config GET_FREE_REGION bool @@ -1304,7 +1330,7 @@ config ARCH_HAS_PTE_SPECIAL bool config MAPPING_DIRTY_HELPERS - bool + bool config KMAP_LOCAL bool @@ -1348,6 +1374,15 @@ config HAVE_ARCH_USERFAULTFD_MINOR help Arch has userfaultfd minor fault support +config USERFAULTFD_RWP + def_bool y + depends on 64BIT && ARCH_HAS_PTE_PROTNONE && HAVE_ARCH_USERFAULTFD_WP + help + Userfaultfd read-write protection (UFFDIO_RWPROTECT) delivers a + userfaultfd notification on every access -- read or write -- to a + protected range, letting userspace observe the working set of a + process. + menuconfig USERFAULTFD bool "Enable userfaultfd() system call" depends on MMU @@ -1355,17 +1390,15 @@ menuconfig USERFAULTFD Enable the userfaultfd() system call that allows to intercept and handle page faults in userland. -if USERFAULTFD config PTE_MARKER_UFFD_WP bool "Userfaultfd write protection support for shmem/hugetlbfs" default y - depends on HAVE_ARCH_USERFAULTFD_WP + depends on USERFAULTFD && HAVE_ARCH_USERFAULTFD_WP help Allows to create marker PTEs for userfaultfd write protection purposes. It is required to enable userfaultfd write protection on file-backed memory types like shmem and hugetlbfs. -endif # USERFAULTFD # multi-gen LRU { config LRU_GEN @@ -1431,11 +1464,18 @@ config NUMA_EMU into virtual nodes when booted with "numa=fake=N", where N is the number of nodes. This is only useful for debugging. +config GENERIC_ARCH_NUMA + bool + select NUMA_MEMBLKS + help + Enable support for generic NUMA implementation. Currently, RISC-V + and ARM64 use it. + config ARCH_HAS_USER_SHADOW_STACK bool help The architecture has hardware support for userspace shadow call - stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). + stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). config HAVE_ARCH_TLB_REMOVE_TABLE def_bool n |