kernel/linux.git/mm/Makefile, branch v6.19.11

Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-12-06T22:01:20+00:00

Pull non-MM updates from Andrew Morton: - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko) fixes a build issue and does some cleanup in ib/sys_info.c - "Implement mul_u64_u64_div_u64_roundup()" (David Laight) enhances the 64-bit math code on behalf of a PWM driver and beefs up the test module for these library functions - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich) makes BPF symbol names, sizes, and line numbers available to the GDB debugger - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang) adds a sysctl which can be used to cause additional info dumping when the hung-task and lockup detectors fire - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu) adds a general base64 encoder/decoder to lib/ and migrates several users away from their private implementations - "rbree: inline rb_first() and rb_last()" (Eric Dumazet) makes TCP a little faster - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin) reworks the KEXEC Handover interfaces in preparation for Live Update Orchestrator (LUO), and possibly for other future clients - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin) increases the flexibility of KEXEC Handover. Also preparation for LUO - "Live Update Orchestrator" (Pasha Tatashin) is a major new feature targeted at cloud environments. Quoting the cover letter: This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. Mike Rappaport merits a mention here, for his extensive review and testing work. - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain) moves the kexec and kdump sysfs entries from /sys/kernel/ to /sys/kernel/kexec/ and adds back-compatibility symlinks which can hopefully be removed one day - "kho: fixes for vmalloc restoration" (Mike Rapoport) fixes a BUG which was being hit during KHO restoration of vmalloc() regions * tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits) calibrate: update header inclusion Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()" vmcoreinfo: track and log recoverable hardware errors kho: fix restoring of contiguous ranges of order-0 pages kho: kho_restore_vmalloc: fix initialization of pages array MAINTAINERS: TPM DEVICE DRIVER: update the W-tag init: replace simple_strtoul with kstrtoul to improve lpj_setup KHO: fix boot failure due to kmemleak access to non-PRESENT pages Documentation/ABI: new kexec and kdump sysfs interface Documentation/ABI: mark old kexec sysfs deprecated kexec: move sysfs entries to /sys/kernel/kexec test_kho: always print restore status kho: free chunks using free_page() instead of kfree() selftests/liveupdate: add kexec test for multiple and empty sessions selftests/liveupdate: add simple kexec-based selftest for LUO selftests/liveupdate: add userspace API selftests docs: add documentation for memfd preservation via LUO mm: memfd_luo: allow preserving memfd liveupdate: luo_file: add private argument to store runtime state mm: shmem: export some functions to internal.h ...

mm: memfd_luo: allow preserving memfd

2025-11-27T22:24:41+00:00

The ability to preserve a memfd allows userspace to use KHO and LUO to transfer its memory contents to the next kernel. This is useful in many ways. For one, it can be used with IOMMUFD as the backing store for IOMMU page tables. Preserving IOMMUFD is essential for performing a hypervisor live update with passthrough devices. memfd support provides the first building block for making that possible. For another, applications with a large amount of memory that takes time to reconstruct, reboots to consume kernel upgrades can be very expensive. memfd with LUO gives those applications reboot-persistent memory that they can use to quickly save and reconstruct that state. While memfd is backed by either hugetlbfs or shmem, currently only support on shmem is added. To be more precise, support for anonymous shmem files is added. The handover to the next kernel is not transparent. All the properties of the file are not preserved; only its memory contents, position, and size. The recreated file gets the UID and GID of the task doing the restore, and the task's cgroup gets charged with the memory. Once preserved, the file cannot grow or shrink, and all its pages are pinned to avoid migrations and swapping. The file can still be read from or written to. Use vmalloc to get the buffer to hold the folios, and preserve it using kho_preserve_vmalloc(). This doesn't have the size limit. Link: https://lkml.kernel.org/r/20251125165850.3389713-15-pasha.tatashin@soleen.com Signed-off-by: Pratyush Yadav Co-developed-by: Pasha Tatashin Signed-off-by: Pasha Tatashin Reviewed-by: Mike Rapoport (Microsoft) Tested-by: David Matlack Cc: Aleksander Lobakin Cc: Alexander Graf Cc: Alice Ryhl Cc: Andriy Shevchenko Cc: anish kumar Cc: Anna Schumaker Cc: Bartosz Golaszewski Cc: Bjorn Helgaas Cc: Borislav Betkov Cc: Chanwoo Choi Cc: Chen Ridong Cc: Chris Li Cc: Christian Brauner Cc: Daniel Wagner Cc: Danilo Krummrich Cc: Dan Williams Cc: David Hildenbrand Cc: David Jeffery Cc: David Rientjes Cc: Greg Kroah-Hartman Cc: Guixin Liu Cc: "H. Peter Anvin" Cc: Hugh Dickins Cc: Ilpo Järvinen Cc: Ingo Molnar Cc: Ira Weiny Cc: Jann Horn Cc: Jason Gunthorpe Cc: Jens Axboe Cc: Joanthan Cameron Cc: Joel Granados Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Lennart Poettering Cc: Leon Romanovsky Cc: Leon Romanovsky Cc: Lukas Wunner Cc: Marc Rutland Cc: Masahiro Yamada Cc: Matthew Maurer Cc: Miguel Ojeda Cc: Myugnjoo Ham Cc: Parav Pandit Cc: Pratyush Yadav Cc: Randy Dunlap Cc: Roman Gushchin Cc: Saeed Mahameed Cc: Samiullah Khawaja Cc: Song Liu Cc: Steven Rostedt Cc: Stuart Hayes Cc: Tejun Heo Cc: Thomas Gleinxer Cc: Thomas Weißschuh Cc: Vincent Guittot Cc: William Tu Cc: Yoann Congal Cc: Zhu Yanjun Cc: Zijun Hu Signed-off-by: Andrew Morton

mm/hugetlb: extract sysctl into hugetlb_sysctl.c

2025-11-20T21:43:57+00:00

Following the extraction of sysfs code, this patch moves the sysctl interface implementation into a dedicated file to further improve code organization and maintainability of the hugetlb subsystem. The following components are moved to mm/hugetlb_sysctl.c: - proc_hugetlb_doulongvec_minmax() - hugetlb_sysctl_handler_common() - hugetlb_sysctl_handler() - hugetlb_mempolicy_sysctl_handler() (CONFIG_NUMA) - hugetlb_overcommit_handler() - hugetlb_table[] sysctl table definition - hugetlb_sysctl_init() The hugetlb_internal.h header file is updated to declare the sysctl initialization function with proper #ifdef guards for configurations without CONFIG_SYSCTL support. The Makefile is updated to compile hugetlb_sysctl.o when CONFIG_HUGETLBFS is enabled. This refactoring reduces the size of hugetlb.c and logically separates the sysctl interface from core hugetlb management code. MAINTAINERS is updated to add new file hugetlb_sysctl.c. No functional changes are introduced; all code is moved as-is from hugetlb.c with consistent formatting. Link: https://lkml.kernel.org/r/5bbee7ab5be71d0bb1aebec38642d7e83526bb7a.1762398359.git.zhuhui@kylinos.cn Signed-off-by: Geliang Tang Signed-off-by: Hui Zhu Cc: David Hildenbrand Cc: Muchun Song Cc: Oscar Salvador Cc: SeongJae Park Signed-off-by: Andrew Morton

mm/hugetlb: extract sysfs into hugetlb_sysfs.c

2025-11-20T21:43:57+00:00

Patch series "mm/hugetlb: refactor sysfs/sysctl interfaces", v5. hugetlb.c has grown significantly and become difficult to maintain. This patch series extracts the sysfs and sysctl interface code into separate dedicated files to improve code organization. The refactoring includes: - Patch 1: Extract sysfs interface into mm/hugetlb_sysfs.c - Patch 2: Extract sysctl interface into mm/hugetlb_sysctl.c No functional changes are introduced in this series. The code is moved as-is, with only minor formatting adjustments for code style consistency. This should make future maintenance and enhancements to the hugetlb subsystem easier. Testing: The patch series has been compile-tested and maintains the same functionality as the original code. This patch (of 2): Currently, hugetlb.c contains both core management logic and sysfs interface implementations, making it difficult to maintain. This patch extracts the sysfs-related code into a dedicated file to improve code organization. The following components are moved to mm/hugetlb_sysfs.c: - sysfs attribute definitions and handlers - sysfs kobject management functions - NUMA per-node hstate attribute registration Several inline helper functions and macros are moved to mm/hugetlb_internal.h: - hstate_is_gigantic_no_runtime() - next_node_allowed() - get_valid_node_allowed() - hstate_next_node_to_alloc() - hstate_next_node_to_free() - for_each_node_mask_to_alloc/to_free macros To support code sharing, these functions are changed from static to exported symbols: - remove_hugetlb_folio() - add_hugetlb_folio() - init_new_hugetlb_folio() - prep_and_add_allocated_folios() - demote_pool_huge_page() - __nr_hugepages_store_common() The Makefile is updated to compile hugetlb_sysfs.o when CONFIG_HUGETLBFS is enabled. This maintains all existing functionality while improving maintainability by separating concerns. MAINTAINERS is updated to add new file hugetlb_sysfs.c. Link: https://lkml.kernel.org/r/cover.1762398359.git.zhuhui@kylinos.cn Link: https://lkml.kernel.org/r/656a03dff7e2bb20e24e841ede81fdca01d21410.1762398359.git.zhuhui@kylinos.cn Signed-off-by: Geliang Tang Signed-off-by: Hui Zhu Cc: David Hildenbrand Cc: Muchun Song Cc: Oscar Salvador Cc: SeongJae Park Signed-off-by: Andrew Morton

mm: remove unused zpool layer

2025-09-21T21:21:59+00:00

With zswap using zsmalloc directly, there are no more in-tree users of this code. Remove it. With zpool gone, zsmalloc is now always a simple dependency and no longer something the user needs to configure. Hide CONFIG_ZSMALLOC from the user and have zswap and zram pull it in as needed. Link: https://lkml.kernel.org/r/20250829162212.208258-3-hannes@cmpxchg.org Signed-off-by: Johannes Weiner Acked-by: SeongJae Park Acked-by: Yosry Ahmed Cc: Chengming Zhou Cc: Nhat Pham Cc: Vitaly Wool Signed-off-by: Andrew Morton

mm: remove mm/io-mapping.c

2025-08-02T19:06:10+00:00

This is dead code, which was used from commit b739f125e4eb ("i915: use io_mapping_map_user") but reverted a month later by commit 0e4fe0c9f2f9 ("Revert "i915: use io_mapping_map_user"") back in 2021. Since then nobody has used it, so remove it. [akpm@linux-foundation.org: update Documentation/core-api/mm-api.rst, per Vlastimil] Link: https://lkml.kernel.org/r/20250725142901.81502-1-lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Acked-by: David Hildenbrand Acked-by: Vlastimil Babka Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton

mm: perform VMA allocation, freeing, duplication in mm

2025-05-13T06:50:48+00:00

Right now these are performed in kernel/fork.c which is odd and a violation of separation of concerns, as well as preventing us from integrating this and related logic into userland VMA testing going forward. There is a fly in the ointment - nommu - mmap.c is not compiled if CONFIG_MMU not set, and neither is vma.c. To square the circle, let's add a new file - vma_init.c. This will be compiled for both CONFIG_MMU and nommu builds, and will also form part of the VMA userland testing. This allows us to de-duplicate code, while maintaining separation of concerns and the ability for us to userland test this logic. Update the VMA userland tests accordingly, additionally adding a detach_free_vma() helper function to correctly detach VMAs before freeing them in test code, as this change was triggering the assert for this. [akpm@linux-foundation.org: remove stray newline, per Liam] Link: https://lkml.kernel.org/r/f97b3a85a6da0196b28070df331b99e22b263be8.1745853549.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Reviewed-by: Pedro Falcato Reviewed-by: David Hildenbrand Reviewed-by: Kees Cook Reviewed-by: Suren Baghdasaryan Reviewed-by: Vlastimil Babka Cc: Al Viro Cc: Christian Brauner Cc: Jan Kara Cc: Jann Horn Signed-off-by: Andrew Morton

mm: establish mm/vma_exec.c for shared exec/mm VMA functionality

2025-05-13T06:50:48+00:00

Patch series "move all VMA allocation, freeing and duplication logic to mm", v3. Currently VMA allocation, freeing and duplication exist in kernel/fork.c, which is a violation of separation of concerns, and leaves these functions exposed to the rest of the kernel when they are in fact internal implementation details. Resolve this by moving this logic to mm, and making it internal to vma.c, vma.h. This also allows us, in future, to provide userland testing around this functionality. We additionally abstract dup_mmap() to mm, being careful to ensure kernel/fork.c acceses this via the mm internal header so it is not exposed elsewhere in the kernel. As part of this change, also abstract initial stack allocation performed in __bprm_mm_init() out of fs code into mm via the create_init_stack_vma(), as this code uses vm_area_alloc() and vm_area_free(). In order to do so sensibly, we introduce a new mm/vma_exec.c file, which contains the code that is shared by mm and exec. This file is added to both memory mapping and exec sections in MAINTAINERS so both sets of maintainers can maintain oversight. As part of this change, we also move relocate_vma_down() to mm/vma_exec.c so all shared mm/exec functionality is kept in one place. We add code shared between nommu and mmu-enabled configurations in order to share VMA allocation, freeing and duplication code correctly while also keeping these functions available in userland VMA testing. This is achieved by adding a mm/vma_init.c file which is also compiled by the userland tests. This patch (of 4): There is functionality that overlaps the exec and memory mapping subsystems. While it properly belongs in mm, it is important that exec maintainers maintain oversight of this functionality correctly. We can establish both goals by adding a new mm/vma_exec.c file which contains these 'glue' functions, and have fs/exec.c import them. As a part of this change, to ensure that proper oversight is achieved, add the file to both the MEMORY MAPPING and EXEC & BINFMT API, ELF sections. scripts/get_maintainer.pl can correctly handle files in multiple entries and this neatly handles the cross-over. [akpm@linux-foundation.org: fix comment typo] Link: https://lkml.kernel.org/r/80f0d0c6-0b68-47f9-ab78-0ab7f74677fc@lucifer.local Link: https://lkml.kernel.org/r/cover.1745853549.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/91f2cee8f17d65214a9d83abb7011aa15f1ea690.1745853549.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Reviewed-by: Suren Baghdasaryan Reviewed-by: Pedro Falcato Reviewed-by: David Hildenbrand Reviewed-by: Kees Cook Reviewed-by: Vlastimil Babka Cc: Al Viro Cc: Christian Brauner Cc: Jan Kara Cc: Jann Horn Signed-off-by: Andrew Morton

mm: rename GENERIC_PTDUMP and PTDUMP_CORE

2025-03-17T07:05:32+00:00

Platforms subscribe into generic ptdump implementation via GENERIC_PTDUMP. But generic ptdump gets enabled via PTDUMP_CORE. These configs combination is confusing as they sound very similar and does not differentiate between platform's feature subscription and feature enablement for ptdump. Rename the configs as ARCH_HAS_PTDUMP and PTDUMP making it more clear and improve readability. Link: https://lkml.kernel.org/r/20250226122404.1927473-6-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Reviewed-by: Christophe Leroy (powerpc) Acked-by: Catalin Marinas [arm64] Cc: Will Deacon Cc: Jonathan Corbet Cc: Marc Zyngier Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Paul Walmsley Cc: Palmer Dabbelt Cc: Heiko Carstens Cc: Vasily Gorbik Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Christophe Leroy Cc: Madhavan Srinivasan Cc: Mark Rutland Cc: Steven Price Signed-off-by: Andrew Morton

mm, swap: remove swap slot cache

2025-03-17T05:06:43+00:00

Slot cache is no longer needed now, removing it and all related code. - vm-scalability with: `usemem --init-time -O -y -x -R -31 1G`, 12G memory cgroup using simulated pmem as SWAP (32G pmem, 32 CPUs), 16 test runs for each case, measuring the total throughput: Before (KB/s) (stdev) After (KB/s) (stdev) Random (4K): 424907.60 (24410.78) 414745.92 (34554.78) Random (64K): 163308.82 (11635.72) 167314.50 (18434.99) Sequential (4K, !-R): 6150056.79 (103205.90) 6321469.06 (115878.16) The performance changes are below noise level. - Build linux kernel with make -j96, using 4K folio with 1.5G memory cgroup limit and 64K folio with 2G memory cgroup limit, on top of tmpfs, 12 test runs, measuring the system time: Before (s) (stdev) After (s) (stdev) make -j96 (4K): 6445.69 (61.95) 6408.80 (69.46) make -j96 (64K): 6841.71 (409.04) 6437.99 (435.55) Similar to above, 64k mTHP case showed a slight improvement. Link: https://lkml.kernel.org/r/20250313165935.63303-7-ryncsn@gmail.com Signed-off-by: Kairui Song Reviewed-by: Baoquan He Cc: Baolin Wang Cc: Barry Song Cc: Chris Li Cc: "Huang, Ying" Cc: Hugh Dickins Cc: Johannes Weiner Cc: Kalesh Singh Cc: Matthew Wilcow (Oracle) Cc: Nhat Pham Cc: Yosry Ahmed Signed-off-by: Andrew Morton