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2025-10-02Merge tag 'mm-stable-2025-10-01-19-00' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "mm, swap: improve cluster scan strategy" from Kairui Song improves performance and reduces the failure rate of swap cluster allocation - "support large align and nid in Rust allocators" from Vitaly Wool permits Rust allocators to set NUMA node and large alignment when perforning slub and vmalloc reallocs - "mm/damon/vaddr: support stat-purpose DAMOS" from Yueyang Pan extend DAMOS_STAT's handling of the DAMON operations sets for virtual address spaces for ops-level DAMOS filters - "execute PROCMAP_QUERY ioctl under per-vma lock" from Suren Baghdasaryan reduces mmap_lock contention during reads of /proc/pid/maps - "mm/mincore: minor clean up for swap cache checking" from Kairui Song performs some cleanup in the swap code - "mm: vm_normal_page*() improvements" from David Hildenbrand provides code cleanup in the pagemap code - "add persistent huge zero folio support" from Pankaj Raghav provides a block layer speedup by optionalls making the huge_zero_pagepersistent, instead of releasing it when its refcount falls to zero - "kho: fixes and cleanups" from Mike Rapoport adds a few touchups to the recently added Kexec Handover feature - "mm: make mm->flags a bitmap and 64-bit on all arches" from Lorenzo Stoakes turns mm_struct.flags into a bitmap. To end the constant struggle with space shortage on 32-bit conflicting with 64-bit's needs - "mm/swapfile.c and swap.h cleanup" from Chris Li cleans up some swap code - "selftests/mm: Fix false positives and skip unsupported tests" from Donet Tom fixes a few things in our selftests code - "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised" from David Hildenbrand "allows individual processes to opt-out of THP=always into THP=madvise, without affecting other workloads on the system". It's a long story - the [1/N] changelog spells out the considerations - "Add and use memdesc_flags_t" from Matthew Wilcox gets us started on the memdesc project. Please see https://kernelnewbies.org/MatthewWilcox/Memdescs and https://blogs.oracle.com/linux/post/introducing-memdesc - "Tiny optimization for large read operations" from Chi Zhiling improves the efficiency of the pagecache read path - "Better split_huge_page_test result check" from Zi Yan improves our folio splitting selftest code - "test that rmap behaves as expected" from Wei Yang adds some rmap selftests - "remove write_cache_pages()" from Christoph Hellwig removes that function and converts its two remaining callers - "selftests/mm: uffd-stress fixes" from Dev Jain fixes some UFFD selftests issues - "introduce kernel file mapped folios" from Boris Burkov introduces the concept of "kernel file pages". Using these permits btrfs to account its metadata pages to the root cgroup, rather than to the cgroups of random inappropriate tasks - "mm/pageblock: improve readability of some pageblock handling" from Wei Yang provides some readability improvements to the page allocator code - "mm/damon: support ARM32 with LPAE" from SeongJae Park teaches DAMON to understand arm32 highmem - "tools: testing: Use existing atomic.h for vma/maple tests" from Brendan Jackman performs some code cleanups and deduplication under tools/testing/ - "maple_tree: Fix testing for 32bit compiles" from Liam Howlett fixes a couple of 32-bit issues in tools/testing/radix-tree.c - "kasan: unify kasan_enabled() and remove arch-specific implementations" from Sabyrzhan Tasbolatov moves KASAN arch-specific initialization code into a common arch-neutral implementation - "mm: remove zpool" from Johannes Weiner removes zspool - an indirection layer which now only redirects to a single thing (zsmalloc) - "mm: task_stack: Stack handling cleanups" from Pasha Tatashin makes a couple of cleanups in the fork code - "mm: remove nth_page()" from David Hildenbrand makes rather a lot of adjustments at various nth_page() callsites, eventually permitting the removal of that undesirable helper function - "introduce kasan.write_only option in hw-tags" from Yeoreum Yun creates a KASAN read-only mode for ARM, using that architecture's memory tagging feature. It is felt that a read-only mode KASAN is suitable for use in production systems rather than debug-only - "mm: hugetlb: cleanup hugetlb folio allocation" from Kefeng Wang does some tidying in the hugetlb folio allocation code - "mm: establish const-correctness for pointer parameters" from Max Kellermann makes quite a number of the MM API functions more accurate about the constness of their arguments. This was getting in the way of subsystems (in this case CEPH) when they attempt to improving their own const/non-const accuracy - "Cleanup free_pages() misuse" from Vishal Moola fixes a number of code sites which were confused over when to use free_pages() vs __free_pages() - "Add Rust abstraction for Maple Trees" from Alice Ryhl makes the mapletree code accessible to Rust. Required by nouveau and by its forthcoming successor: the new Rust Nova driver - "selftests/mm: split_huge_page_test: split_pte_mapped_thp improvements" from David Hildenbrand adds a fix and some cleanups to the thp selftesting code - "mm, swap: introduce swap table as swap cache (phase I)" from Chris Li and Kairui Song is the first step along the path to implementing "swap tables" - a new approach to swap allocation and state tracking which is expected to yield speed and space improvements. This patchset itself yields a 5-20% performance benefit in some situations - "Some ptdesc cleanups" from Matthew Wilcox utilizes the new memdesc layer to clean up the ptdesc code a little - "Fix va_high_addr_switch.sh test failure" from Chunyu Hu fixes some issues in our 5-level pagetable selftesting code - "Minor fixes for memory allocation profiling" from Suren Baghdasaryan addresses a couple of minor issues in relatively new memory allocation profiling feature - "Small cleanups" from Matthew Wilcox has a few cleanups in preparation for more memdesc work - "mm/damon: add addr_unit for DAMON_LRU_SORT and DAMON_RECLAIM" from Quanmin Yan makes some changes to DAMON in furtherance of supporting arm highmem - "selftests/mm: Add -Wunreachable-code and fix warnings" from Muhammad Anjum adds that compiler check to selftests code and fixes the fallout, by removing dead code - "Improvements to Victim Process Thawing and OOM Reaper Traversal Order" from zhongjinji makes a number of improvements in the OOM killer: mainly thawing a more appropriate group of victim threads so they can release resources - "mm/damon: misc fixups and improvements for 6.18" from SeongJae Park is a bunch of small and unrelated fixups for DAMON - "mm/damon: define and use DAMON initialization check function" from SeongJae Park implement reliability and maintainability improvements to a recently-added bug fix - "mm/damon/stat: expose auto-tuned intervals and non-idle ages" from SeongJae Park provides additional transparency to userspace clients of the DAMON_STAT information - "Expand scope of khugepaged anonymous collapse" from Dev Jain removes some constraints on khubepaged's collapsing of anon VMAs. It also increases the success rate of MADV_COLLAPSE against an anon vma - "mm: do not assume file == vma->vm_file in compat_vma_mmap_prepare()" from Lorenzo Stoakes moves us further towards removal of file_operations.mmap(). This patchset concentrates upon clearing up the treatment of stacked filesystems - "mm: Improve mlock tracking for large folios" from Kiryl Shutsemau provides some fixes and improvements to mlock's tracking of large folios. /proc/meminfo's "Mlocked" field became more accurate - "mm/ksm: Fix incorrect accounting of KSM counters during fork" from Donet Tom fixes several user-visible KSM stats inaccuracies across forks and adds selftest code to verify these counters - "mm_slot: fix the usage of mm_slot_entry" from Wei Yang addresses some potential but presently benign issues in KSM's mm_slot handling * tag 'mm-stable-2025-10-01-19-00' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (372 commits) mm: swap: check for stable address space before operating on the VMA mm: convert folio_page() back to a macro mm/khugepaged: use start_addr/addr for improved readability hugetlbfs: skip VMAs without shareable locks in hugetlb_vmdelete_list alloc_tag: fix boot failure due to NULL pointer dereference mm: silence data-race in update_hiwater_rss mm/memory-failure: don't select MEMORY_ISOLATION mm/khugepaged: remove definition of struct khugepaged_mm_slot mm/ksm: get mm_slot by mm_slot_entry() when slot is !NULL hugetlb: increase number of reserving hugepages via cmdline selftests/mm: add fork inheritance test for ksm_merging_pages counter mm/ksm: fix incorrect KSM counter handling in mm_struct during fork drivers/base/node: fix double free in register_one_node() mm: remove PMD alignment constraint in execmem_vmalloc() mm/memory_hotplug: fix typo 'esecially' -> 'especially' mm/rmap: improve mlock tracking for large folios mm/filemap: map entire large folio faultaround mm/fault: try to map the entire file folio in finish_fault() mm/rmap: mlock large folios in try_to_unmap_one() mm/rmap: fix a mlock race condition in folio_referenced_one() ...
2025-10-02Merge tag 'for-6.18/block-20250929' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux Pull block updates from Jens Axboe: - NVMe pull request via Keith: - FC target fixes (Daniel) - Authentication fixes and updates (Martin, Chris) - Admin controller handling (Kamaljit) - Target lockdep assertions (Max) - Keep-alive updates for discovery (Alastair) - Suspend quirk (Georg) - MD pull request via Yu: - Add support for a lockless bitmap. A key feature for the new bitmap are that the IO fastpath is lockless. If a user issues lots of write IO to the same bitmap bit in a short time, only the first write has additional overhead to update bitmap bit, no additional overhead for the following writes. By supporting only resync or recover written data, means in the case creating new array or replacing with a new disk, there is no need to do a full disk resync/recovery. - Switch ->getgeo() and ->bios_param() to using struct gendisk rather than struct block_device. - Rust block changes via Andreas. This series adds configuration via configfs and remote completion to the rnull driver. The series also includes a set of changes to the rust block device driver API: a few cleanup patches, and a few features supporting the rnull changes. The series removes the raw buffer formatting logic from `kernel::block` and improves the logic available in `kernel::string` to support the same use as the removed logic. - floppy arch cleanups - Reduce the number of dereferencing needed for ublk commands - Restrict supported sockets for nbd. Mostly done to eliminate a class of issues perpetually reported by syzbot, by using nonsensical socket setups. - A few s390 dasd block fixes - Fix a few issues around atomic writes - Improve DMA interation for integrity requests - Improve how iovecs are treated with regards to O_DIRECT aligment constraints. We used to require each segment to adhere to the constraints, now only the request as a whole needs to. - Clean up and improve p2p support, enabling use of p2p for metadata payloads - Improve locking of request lookup, using SRCU where appropriate - Use page references properly for brd, avoiding very long RCU sections - Fix ordering of recursively submitted IOs - Clean up and improve updating nr_requests for a live device - Various fixes and cleanups * tag 'for-6.18/block-20250929' of git://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux: (164 commits) s390/dasd: enforce dma_alignment to ensure proper buffer validation s390/dasd: Return BLK_STS_INVAL for EINVAL from do_dasd_request ublk: remove redundant zone op check in ublk_setup_iod() nvme: Use non zero KATO for persistent discovery connections nvmet: add safety check for subsys lock nvme-core: use nvme_is_io_ctrl() for I/O controller check nvme-core: do ioccsz/iorcsz validation only for I/O controllers nvme-core: add method to check for an I/O controller blk-cgroup: fix possible deadlock while configuring policy blk-mq: fix null-ptr-deref in blk_mq_free_tags() from error path blk-mq: Fix more tag iteration function documentation selftests: ublk: fix behavior when fio is not installed ublk: don't access ublk_queue in ublk_unmap_io() ublk: pass ublk_io to __ublk_complete_rq() ublk: don't access ublk_queue in ublk_need_complete_req() ublk: don't access ublk_queue in ublk_check_commit_and_fetch() ublk: don't pass ublk_queue to ublk_fetch() ublk: don't access ublk_queue in ublk_config_io_buf() ublk: don't access ublk_queue in ublk_check_fetch_buf() ublk: pass q_id and tag to __ublk_check_and_get_req() ...
2025-09-30Merge tag 'x86_cache_for_v6.18_rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull x86 resource control updates from Borislav Petkov: "Add support on AMD for assigning QoS bandwidth counters to resources (RMIDs) with the ability for those resources to be tracked by the counters as long as they're assigned to them. Previously, due to hw limitations, bandwidth counts from untracked resources would get lost when those resources are not tracked. Refactor the code and user interfaces to be able to also support other, similar features on ARM, for example" * tag 'x86_cache_for_v6.18_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (35 commits) fs/resctrl: Fix counter auto-assignment on mkdir with mbm_event enabled MAINTAINERS: resctrl: Add myself as reviewer x86/resctrl: Configure mbm_event mode if supported fs/resctrl: Introduce the interface to switch between monitor modes fs/resctrl: Disable BMEC event configuration when mbm_event mode is enabled fs/resctrl: Introduce the interface to modify assignments in a group fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group fs/resctrl: Auto assign counters on mkdir and clean up on group removal fs/resctrl: Introduce mbm_assign_on_mkdir to enable assignments on mkdir fs/resctrl: Provide interface to update the event configurations fs/resctrl: Add event configuration directory under info/L3_MON/ fs/resctrl: Support counter read/reset with mbm_event assignment mode x86/resctrl: Implement resctrl_arch_reset_cntr() and resctrl_arch_cntr_read() x86/resctrl: Refactor resctrl_arch_rmid_read() fs/resctrl: Introduce counter ID read, reset calls in mbm_event mode fs/resctrl: Pass struct rdtgroup instead of individual members fs/resctrl: Add the functionality to unassign MBM events fs/resctrl: Add the functionality to assign MBM events x86,fs/resctrl: Implement resctrl_arch_config_cntr() to assign a counter with ABMC fs/resctrl: Introduce event configuration field in struct mon_evt ...
2025-09-29Remove bcachefs core codeLinus Torvalds
bcachefs was marked 'externally maintained' in 6.17 but the code remained to make the transition smoother. It's now a DKMS module, making the in-kernel code stale, so remove it to avoid any version confusion. Link: https://lore.kernel.org/linux-bcachefs/yokpt2d2g2lluyomtqrdvmkl3amv3kgnipmenobkpgx537kay7@xgcgjviv3n7x/T/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2025-09-29Merge tag 'vfs-6.18-rc1.async' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs async directory updates from Christian Brauner: "This contains further preparatory changes for the asynchronous directory locking scheme: - Add lookup_one_positive_killable() which allows overlayfs to perform lookup that won't block on a fatal signal - Unify the mount idmap handling in struct renamedata as a rename can only happen within a single mount - Introduce kern_path_parent() for audit which sets the path to the parent and returns a dentry for the target without holding any locks on return - Rename kern_path_locked() as it is only used to prepare for the removal of an object from the filesystem: kern_path_locked() => start_removing_path() kern_path_create() => start_creating_path() user_path_create() => start_creating_user_path() user_path_locked_at() => start_removing_user_path_at() done_path_create() => end_creating_path() NA => end_removing_path()" * tag 'vfs-6.18-rc1.async' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: debugfs: rename start_creating() to debugfs_start_creating() VFS: rename kern_path_locked() and related functions. VFS/audit: introduce kern_path_parent() for audit VFS: unify old_mnt_idmap and new_mnt_idmap in renamedata VFS: discard err2 in filename_create() VFS/ovl: add lookup_one_positive_killable()
2025-09-29Merge tag 'vfs-6.18-rc1.mount' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs mount updates from Christian Brauner: "This contains some work around mount api handling: - Output the warning message for mnt_too_revealing() triggered during fsmount() to the fscontext log. This makes it possible for the mount tool to output appropriate warnings on the command line. For example, with the newest fsopen()-based mount(8) from util-linux, the error messages now look like: # mount -t proc proc /tmp mount: /tmp: fsmount() failed: VFS: Mount too revealing. dmesg(1) may have more information after failed mount system call. - Do not consume fscontext log entries when returning -EMSGSIZE Userspace generally expects APIs that return -EMSGSIZE to allow for them to adjust their buffer size and retry the operation. However, the fscontext log would previously clear the message even in the -EMSGSIZE case. Given that it is very cheap for us to check whether the buffer is too small before we remove the message from the ring buffer, let's just do that instead. - Drop an unused argument from do_remount()" * tag 'vfs-6.18-rc1.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: vfs: fs/namespace.c: remove ms_flags argument from do_remount selftests/filesystems: add basic fscontext log tests fscontext: do not consume log entries when returning -EMSGSIZE vfs: output mount_too_revealing() errors to fscontext docs/vfs: Remove mentions to the old mount API helpers fscontext: add custom-prefix log helpers fs: Remove mount_bdev fs: Remove mount_nodev
2025-09-23VFS: rename kern_path_locked() and related functions.NeilBrown
kern_path_locked() is now only used to prepare for removing an object from the filesystem (and that is the only credible reason for wanting a positive locked dentry). Thus it corresponds to kern_path_create() and so should have a corresponding name. Unfortunately the name "kern_path_create" is somewhat misleading as it doesn't actually create anything. The recently added simple_start_creating() provides a better pattern I believe. The "start" can be matched with "end" to bracket the creating or removing. So this patch changes names: kern_path_locked -> start_removing_path kern_path_create -> start_creating_path user_path_create -> start_creating_user_path user_path_locked_at -> start_removing_user_path_at done_path_create -> end_creating_path and also introduces end_removing_path() which is identical to end_creating_path(). __start_removing_path (which was __kern_path_locked) is enhanced to call mnt_want_write() for consistency with the start_creating_path(). Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: NeilBrown <neil@brown.name> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-21alloc_tag: mark inaccurate allocation counters in /proc/allocinfo outputSuren Baghdasaryan
While rare, memory allocation profiling can contain inaccurate counters if slab object extension vector allocation fails. That allocation might succeed later but prior to that, slab allocations that would have used that object extension vector will not be accounted for. To indicate incorrect counters, "accurate:no" marker is appended to the call site line in the /proc/allocinfo output. Bump up /proc/allocinfo version to reflect the change in the file format and update documentation. Example output with invalid counters: allocinfo - version: 2.0 0 0 arch/x86/kernel/kdebugfs.c:105 func:create_setup_data_nodes 0 0 arch/x86/kernel/alternative.c:2090 func:alternatives_smp_module_add 0 0 arch/x86/kernel/alternative.c:127 func:__its_alloc accurate:no 0 0 arch/x86/kernel/fpu/regset.c:160 func:xstateregs_set 0 0 arch/x86/kernel/fpu/xstate.c:1590 func:fpstate_realloc 0 0 arch/x86/kernel/cpu/aperfmperf.c:379 func:arch_enable_hybrid_capacity_scale 0 0 arch/x86/kernel/cpu/amd_cache_disable.c:258 func:init_amd_l3_attrs 49152 48 arch/x86/kernel/cpu/mce/core.c:2709 func:mce_device_create accurate:no 32768 1 arch/x86/kernel/cpu/mce/genpool.c:132 func:mce_gen_pool_create 0 0 arch/x86/kernel/cpu/mce/amd.c:1341 func:mce_threshold_create_device [surenb@google.com: document new "accurate:no" marker] Fixes: 39d117e04d15 ("alloc_tag: mark inaccurate allocation counters in /proc/allocinfo output") [akpm@linux-foundation.org: simplification per Usama, reflow text] [akpm@linux-foundation.org: add newline to prevent docs warning, per Randy] Link: https://lkml.kernel.org/r/20250915230224.4115531-1-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Usama Arif <usamaarif642@gmail.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: David Rientjes <rientjes@google.com> Cc: David Wang <00107082@163.com> Cc: Kent Overstreet <kent.overstreet@linux.dev> Cc: Pasha Tatashin <pasha.tatashin@soleen.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Sourav Panda <souravpanda@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-15fs: rename generic_delete_inode() and generic_drop_inode()Mateusz Guzik
generic_delete_inode() is rather misleading for what the routine is doing. inode_just_drop() should be much clearer. The new naming is inconsistent with generic_drop_inode(), so rename that one as well with inode_ as the suffix. No functional changes. Signed-off-by: Mateusz Guzik <mjguzik@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-15fs/resctrl: Introduce the interface to switch between monitor modesBabu Moger
Resctrl subsystem can support two monitoring modes, "mbm_event" or "default". In mbm_event mode, monitoring event can only accumulate data while it is backed by a hardware counter. In "default" mode, resctrl assumes there is a hardware counter for each event within every CTRL_MON and MON group. Introduce mbm_assign_mode resctrl file to switch between mbm_event and default modes. Example: To list the MBM monitor modes supported: $ cat /sys/fs/resctrl/info/L3_MON/mbm_assign_mode [mbm_event] default To enable the "mbm_event" counter assignment mode: $ echo "mbm_event" > /sys/fs/resctrl/info/L3_MON/mbm_assign_mode To enable the "default" monitoring mode: $ echo "default" > /sys/fs/resctrl/info/L3_MON/mbm_assign_mode Reset MBM event counters automatically as part of changing the mode. Clear both architectural and non-architectural event states to prevent overflow conditions during the next event read. Clear assignable counter configuration on all the domains. Also, enable auto assignment when switching to "mbm_event" mode. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce the interface to modify assignments in a groupBabu Moger
Enable the mbm_l3_assignments resctrl file to be used to modify counter assignments of CTRL_MON and MON groups when the "mbm_event" counter assignment mode is enabled. Process the assignment modifications in the following format: <Event>:<Domain id>=<Assignment state>;<Domain id>=<Assignment state> Event: A valid MBM event in the /sys/fs/resctrl/info/L3_MON/event_configs directory. Domain ID: A valid domain ID. When writing, '*' applies the changes to all domains. Assignment states: _ : Unassign a counter. e : Assign a counter exclusively. Examples: $ cd /sys/fs/resctrl $ cat /sys/fs/resctrl/mbm_L3_assignments mbm_total_bytes:0=e;1=e mbm_local_bytes:0=e;1=e To unassign the counter associated with the mbm_total_bytes event on domain 0: $ echo "mbm_total_bytes:0=_" > mbm_L3_assignments $ cat /sys/fs/resctrl/mbm_L3_assignments mbm_total_bytes:0=_;1=e mbm_local_bytes:0=e;1=e To unassign the counter associated with the mbm_total_bytes event on all the domains: $ echo "mbm_total_bytes:*=_" > mbm_L3_assignments $ cat /sys/fs/resctrl/mbm_L3_assignments mbm_total_bytes:0=_;1=_ mbm_local_bytes:0=e;1=e Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce mbm_L3_assignments to list assignments in a groupBabu Moger
Introduce the mbm_L3_assignments resctrl file associated with CTRL_MON and MON resource groups to display the counter assignment states of the resource group when "mbm_event" counter assignment mode is enabled. Display the list in the following format: <Event>:<Domain id>=<Assignment state>;<Domain id>=<Assignment state> Event: A valid MBM event listed in /sys/fs/resctrl/info/L3_MON/event_configs directory. Domain ID: A valid domain ID. The assignment state can be one of the following: _ : No counter assigned. e : Counter assigned exclusively. Example: To list the assignment states for the default group $ cd /sys/fs/resctrl $ cat /sys/fs/resctrl/mbm_L3_assignments mbm_total_bytes:0=e;1=e mbm_local_bytes:0=e;1=e Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce mbm_assign_on_mkdir to enable assignments on mkdirBabu Moger
The "mbm_event" counter assignment mode allows users to assign a hardware counter to an RMID, event pair and monitor the bandwidth as long as it is assigned. Introduce a user-configurable option that determines if a counter will automatically be assigned to an RMID, event pair when its associated monitor group is created via mkdir. Accessible when "mbm_event" counter assignment mode is enabled. Suggested-by: Peter Newman <peternewman@google.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Provide interface to update the event configurationsBabu Moger
When "mbm_event" counter assignment mode is enabled, users can modify the event configuration by writing to the 'event_filter' resctrl file. The event configurations for mbm_event mode are located in /sys/fs/resctrl/info/L3_MON/event_configs/. Update the assignments of all CTRL_MON and MON resource groups when the event configuration is modified. Example: $ mount -t resctrl resctrl /sys/fs/resctrl $ cd /sys/fs/resctrl/ $ cat info/L3_MON/event_configs/mbm_local_bytes/event_filter local_reads,local_non_temporal_writes,local_reads_slow_memory $ echo "local_reads,local_non_temporal_writes" > info/L3_MON/event_configs/mbm_total_bytes/event_filter $ cat info/L3_MON/event_configs/mbm_total_bytes/event_filter local_reads,local_non_temporal_writes Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Add event configuration directory under info/L3_MON/Babu Moger
The "mbm_event" counter assignment mode allows the user to assign a hardware counter to an RMID, event pair and monitor the bandwidth as long as it is assigned. The user can specify the memory transaction(s) for the counter to track. When this mode is supported, the /sys/fs/resctrl/info/L3_MON/event_configs directory contains a sub-directory for each MBM event that can be assigned to a counter. The MBM event sub-directory contains a file named "event_filter" that is used to view and modify which memory transactions the MBM event is configured with. Create /sys/fs/resctrl/info/L3_MON/event_configs directory on resctrl mount and pre-populate it with directories for the two existing MBM events: mbm_total_bytes and mbm_local_bytes. Create the "event_filter" file within each MBM event directory with the needed *show() that displays the memory transactions with which the MBM event is configured. Example: $ mount -t resctrl resctrl /sys/fs/resctrl $ cd /sys/fs/resctrl/ $ cat info/L3_MON/event_configs/mbm_total_bytes/event_filter local_reads,remote_reads,local_non_temporal_writes, remote_non_temporal_writes,local_reads_slow_memory, remote_reads_slow_memory,dirty_victim_writes_all $ cat info/L3_MON/event_configs/mbm_local_bytes/event_filter local_reads,local_non_temporal_writes,local_reads_slow_memory Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Support counter read/reset with mbm_event assignment modeBabu Moger
When "mbm_event" counter assignment mode is enabled, the architecture requires a counter ID to read the event data. Introduce an is_mbm_cntr field in struct rmid_read to indicate whether counter assignment mode is in use. Update the logic to call resctrl_arch_cntr_read() and resctrl_arch_reset_cntr() when the assignment mode is active. Report 'Unassigned' in case the user attempts to read an event without assigning a hardware counter. Suggested-by: Reinette Chatre <reinette.chatre@intel.com> Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce interface to display number of free MBM countersBabu Moger
Introduce the "available_mbm_cntrs" resctrl file to display the number of counters available for assignment in each domain when "mbm_event" mode is enabled. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Add resctrl file to display number of assignable countersBabu Moger
The "mbm_event" counter assignment mode allows users to assign a hardware counter to an RMID, event pair and monitor bandwidth usage as long as it is assigned. The hardware continues to track the assigned counter until it is explicitly unassigned by the user. Create 'num_mbm_cntrs' resctrl file that displays the number of counters supported in each domain. 'num_mbm_cntrs' is only visible to user space when the system supports "mbm_event" mode. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15fs/resctrl: Introduce the interface to display monitoring modesBabu Moger
Introduce the resctrl file "mbm_assign_mode" to list the supported counter assignment modes. The "mbm_event" counter assignment mode allows users to assign a hardware counter to an RMID, event pair and monitor bandwidth usage as long as it is assigned. The hardware continues to track the assigned counter until it is explicitly unassigned by the user. Each event within a resctrl group can be assigned independently in this mode. On AMD systems "mbm_event" mode is backed by the ABMC (Assignable Bandwidth Monitoring Counters) hardware feature and is enabled by default. The "default" mode is the existing mode that works without the explicit counter assignment, instead relying on dynamic counter assignment by hardware that may result in hardware not dedicating a counter resulting in monitoring data reads returning "Unavailable". Provide an interface to display the monitor modes on the system. $ cat /sys/fs/resctrl/info/L3_MON/mbm_assign_mode [mbm_event] default Add IS_ENABLED(CONFIG_RESCTRL_ASSIGN_FIXED) check to support Arm64. On x86, CONFIG_RESCTRL_ASSIGN_FIXED is not defined. On Arm64, it will be defined when the "mbm_event" mode is supported. Add IS_ENABLED(CONFIG_RESCTRL_ASSIGN_FIXED) check early to ensure the user interface remains compatible with upcoming Arm64 support. IS_ENABLED() safely evaluates to 0 when the configuration is not defined. As a result, for MPAM, the display would be either: [default] or [mbm_event] Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-15x86/resctrl: Add ABMC feature in the command line optionsBabu Moger
Add a kernel command-line parameter to enable or disable the exposure of the ABMC (Assignable Bandwidth Monitoring Counters) hardware feature to resctrl. Signed-off-by: Babu Moger <babu.moger@amd.com> Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de> Reviewed-by: Reinette Chatre <reinette.chatre@intel.com> Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
2025-09-13prctl: extend PR_SET_THP_DISABLE to optionally exclude VM_HUGEPAGEDavid Hildenbrand
Patch series "prctl: extend PR_SET_THP_DISABLE to only provide THPs when advised", v5. This will allow individual processes to opt-out of THP = "always" into THP = "madvise", without affecting other workloads on the system. This has been extensively discussed on the mailing list and has been summarized very well by David in the first patch which also includes the links to alternatives, please refer to the first patch commit message for the motivation for this series. Patch 1 adds the PR_THP_DISABLE_EXCEPT_ADVISED flag to implement this, along with the MMF changes. Patch 2 is a cleanup patch for tva_flags that will allow the forced collapse case to be transmitted to vma_thp_disabled (which is done in patch 3). Patch 4 adds documentation for PR_SET_THP_DISABLE/PR_GET_THP_DISABLE. Patches 6-7 implement the selftests for PR_SET_THP_DISABLE for completely disabling THPs (old behaviour) and only enabling it at advise (PR_THP_DISABLE_EXCEPT_ADVISED). This patch (of 7): People want to make use of more THPs, for example, moving from the "never" system policy to "madvise", or from "madvise" to "always". While this is great news for every THP desperately waiting to get allocated out there, apparently there are some workloads that require a bit of care during that transition: individual processes may need to opt-out from this behavior for various reasons, and this should be permitted without needing to make all other workloads on the system similarly opt-out. The following scenarios are imaginable: (1) Switch from "none" system policy to "madvise"/"always", but keep THPs disabled for selected workloads. (2) Stay at "none" system policy, but enable THPs for selected workloads, making only these workloads use the "madvise" or "always" policy. (3) Switch from "madvise" system policy to "always", but keep the "madvise" policy for selected workloads: allocate THPs only when advised. (4) Stay at "madvise" system policy, but enable THPs even when not advised for selected workloads -- "always" policy. Once can emulate (2) through (1), by setting the system policy to "madvise"/"always" while disabling THPs for all processes that don't want THPs. It requires configuring all workloads, but that is a user-space problem to sort out. (4) can be emulated through (3) in a similar way. Back when (1) was relevant in the past, as people started enabling THPs, we added PR_SET_THP_DISABLE, so relevant workloads that were not ready yet (i.e., used by Redis) were able to just disable THPs completely. Redis still implements the option to use this interface to disable THPs completely. With PR_SET_THP_DISABLE, we added a way to force-disable THPs for a workload -- a process, including fork+exec'ed process hierarchy. That essentially made us support (1): simply disable THPs for all workloads that are not ready for THPs yet, while still enabling THPs system-wide. The quest for handling (3) and (4) started, but current approaches (completely new prctl, options to set other policies per process, alternatives to prctl -- mctrl, cgroup handling) don't look particularly promising. Likely, the future will use bpf or something similar to implement better policies, in particular to also make better decisions about THP sizes to use, but this will certainly take a while as that work just started. Long story short: a simple enable/disable is not really suitable for the future, so we're not willing to add completely new toggles. While we could emulate (3)+(4) through (1)+(2) by simply disabling THPs completely for these processes, this is a step backwards, because these processes can no longer allocate THPs in regions where THPs were explicitly advised: regions flagged as VM_HUGEPAGE. Apparently, that imposes a problem for relevant workloads, because "not THPs" is certainly worse than "THPs only when advised". Could we simply relax PR_SET_THP_DISABLE, to "disable THPs unless not explicitly advised by the app through MAD_HUGEPAGE"? *maybe*, but this would change the documented semantics quite a bit, and the versatility to use it for debugging purposes, so I am not 100% sure that is what we want -- although it would certainly be much easier. So instead, as an easy way forward for (3) and (4), add an option to make PR_SET_THP_DISABLE disable *less* THPs for a process. In essence, this patch: (A) Adds PR_THP_DISABLE_EXCEPT_ADVISED, to be used as a flag in arg3 of prctl(PR_SET_THP_DISABLE) when disabling THPs (arg2 != 0). prctl(PR_SET_THP_DISABLE, 1, PR_THP_DISABLE_EXCEPT_ADVISED). (B) Makes prctl(PR_GET_THP_DISABLE) return 3 if PR_THP_DISABLE_EXCEPT_ADVISED was set while disabling. Previously, it would return 1 if THPs were disabled completely. Now it returns the set flags as well: 3 if PR_THP_DISABLE_EXCEPT_ADVISED was set. (C) Renames MMF_DISABLE_THP to MMF_DISABLE_THP_COMPLETELY, to express the semantics clearly. Fortunately, there are only two instances outside of prctl() code. (D) Adds MMF_DISABLE_THP_EXCEPT_ADVISED to express "no THP except for VMAs with VM_HUGEPAGE" -- essentially "thp=madvise" behavior Fortunately, we only have to extend vma_thp_disabled(). (E) Indicates "THP_enabled: 0" in /proc/pid/status only if THPs are disabled completely Only indicating that THPs are disabled when they are really disabled completely, not only partially. For now, we don't add another interface to obtained whether THPs are disabled partially (PR_THP_DISABLE_EXCEPT_ADVISED was set). If ever required, we could add a new entry. The documented semantics in the man page for PR_SET_THP_DISABLE "is inherited by a child created via fork(2) and is preserved across execve(2)" is maintained. This behavior, for example, allows for disabling THPs for a workload through the launching process (e.g., systemd where we fork() a helper process to then exec()). For now, MADV_COLLAPSE will *fail* in regions without VM_HUGEPAGE and VM_NOHUGEPAGE. As MADV_COLLAPSE is a clear advise that user space thinks a THP is a good idea, we'll enable that separately next (requiring a bit of cleanup first). There is currently not way to prevent that a process will not issue PR_SET_THP_DISABLE itself to re-enable THP. There are not really known users for re-enabling it, and it's against the purpose of the original interface. So if ever required, we could investigate just forbidding to re-enable them, or make this somehow configurable. Link: https://lkml.kernel.org/r/20250815135549.130506-1-usamaarif642@gmail.com Link: https://lkml.kernel.org/r/20250815135549.130506-2-usamaarif642@gmail.com Acked-by: Zi Yan <ziy@nvidia.com> Acked-by: Usama Arif <usamaarif642@gmail.com> Tested-by: Usama Arif <usamaarif642@gmail.com> Signed-off-by: David Hildenbrand <david@redhat.com> Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Signed-off-by: Usama Arif <usamaarif642@gmail.com> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Baolin Wang <baolin.wang@linux.alibaba.com> Cc: Barry Song <baohua@kernel.org> Cc: Dev Jain <dev.jain@arm.com> Cc: Jann Horn <jannh@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Mariano Pache <npache@redhat.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Rik van Riel <riel@surriel.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: SeongJae Park <sj@kernel.org> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Yafang <laoar.shao@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-09-02procfs: add "pidns" mount optionAleksa Sarai
Since the introduction of pid namespaces, their interaction with procfs has been entirely implicit in ways that require a lot of dancing around by programs that need to construct sandboxes with different PID namespaces. Being able to explicitly specify the pid namespace to use when constructing a procfs super block will allow programs to no longer need to fork off a process which does then does unshare(2) / setns(2) and forks again in order to construct a procfs in a pidns. So, provide a "pidns" mount option which allows such users to just explicitly state which pid namespace they want that procfs instance to use. This interface can be used with fsconfig(2) either with a file descriptor or a path: fsconfig(procfd, FSCONFIG_SET_FD, "pidns", NULL, nsfd); fsconfig(procfd, FSCONFIG_SET_STRING, "pidns", "/proc/self/ns/pid", 0); or with classic mount(2) / mount(8): // mount -t proc -o pidns=/proc/self/ns/pid proc /tmp/proc mount("proc", "/tmp/proc", "proc", MS_..., "pidns=/proc/self/ns/pid"); As this new API is effectively shorthand for setns(2) followed by mount(2), the permission model for this mirrors pidns_install() to avoid opening up new attack surfaces by loosening the existing permission model. In order to avoid having to RCU-protect all users of proc_pid_ns() (to avoid UAFs), attempting to reconfigure an existing procfs instance's pid namespace will error out with -EBUSY. Creating new procfs instances is quite cheap, so this should not be an impediment to most users, and lets us avoid a lot of churn in fs/proc/* for a feature that it seems unlikely userspace would use. Signed-off-by: Aleksa Sarai <cyphar@cyphar.com> Link: https://lore.kernel.org/20250805-procfs-pidns-api-v4-2-705f984940e7@cyphar.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-13block: switch ->getgeo() to struct gendiskAl Viro
Instances are happier that way and it makes more sense anyway - the only part of the result that is related to partition we are given is the start sector, and that has been filled in by the caller. Everything else is a function of the disk. Only one instance (DASD) is ever looking at anything other than bdev->bd_disk and that one is trivial to adjust. Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2025-08-11docs/vfs: Remove mentions to the old mount API helpersPedro Falcato
Now that mount_bdev(), mount_nodev() and mount_single() have all been removed, remove mentions to them in vfs.rst. While we're at it, redirect people looking for mount API docs to mount_api.rst (which documents the newer API). Signed-off-by: Pedro Falcato <pfalcato@suse.de> Link: https://lore.kernel.org/20250723132156.225410-4-pfalcato@suse.de Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-08-04Merge tag 'f2fs-for-6.17-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs Pull f2fs updates from Jaegeuk Kim: "Three main updates: folio conversion by Matthew, switch to a new mount API by Hongbo and Eric, and several sysfs entries to tune GCs for ZUFS with finer granularity by Daeho. There are also patches to address bugs and issues in the existing features such as GCs, file pinning, write-while-dio-read, contingous block allocation, and memory access violations. Enhancements: - switch to new mount API and folio conversion - add sysfs nodes to controle F2FS GCs for ZUFS - improve performance on the nat entry cache - drop inode from the donation list when the last file is closed - avoid splitting bio when reading multiple pages Bug fixes: - fix to trigger foreground gc during f2fs_map_blocks() in lfs mode - make sure zoned device GC to use FG_GC in shortage of free section - fix to calculate dirty data during has_not_enough_free_secs() - fix to update upper_p in __get_secs_required() correctly - wait for inflight dio completion, excluding pinned files read using dio - don't break allocation when crossing contiguous sections - vm_unmap_ram() may be called from an invalid context - fix to avoid out-of-boundary access in dnode page - fix to avoid panic in f2fs_evict_inode - fix to avoid UAF in f2fs_sync_inode_meta() - fix to use f2fs_is_valid_blkaddr_raw() in do_write_page() - fix UAF of f2fs_inode_info in f2fs_free_dic - fix to avoid invalid wait context issue - fix bio memleak when committing super block - handle nat.blkaddr corruption in f2fs_get_node_info() In addition, there are also clean-ups and minor bug fixes" * tag 'f2fs-for-6.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (109 commits) f2fs: drop inode from the donation list when the last file is closed f2fs: add gc_boost_gc_greedy sysfs node f2fs: add gc_boost_gc_multiple sysfs node f2fs: fix to trigger foreground gc during f2fs_map_blocks() in lfs mode f2fs: fix to calculate dirty data during has_not_enough_free_secs() f2fs: fix to update upper_p in __get_secs_required() correctly f2fs: directly add newly allocated pre-dirty nat entry to dirty set list f2fs: avoid redundant clean nat entry move in lru list f2fs: zone: wait for inflight dio completion, excluding pinned files read using dio f2fs: ignore valid ratio when free section count is low f2fs: don't break allocation when crossing contiguous sections f2fs: remove unnecessary tracepoint enabled check f2fs: merge the two conditions to avoid code duplication f2fs: vm_unmap_ram() may be called from an invalid context f2fs: fix to avoid out-of-boundary access in dnode page f2fs: switch to the new mount api f2fs: introduce fs_context_operation structure f2fs: separate the options parsing and options checking f2fs: Add f2fs_fs_context to record the mount options f2fs: Allow sbi to be NULL in f2fs_printk ...
2025-07-31Merge tag 'mm-stable-2025-07-30-15-25' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "As usual, many cleanups. The below blurbiage describes 42 patchsets. 21 of those are partially or fully cleanup work. "cleans up", "cleanup", "maintainability", "rationalizes", etc. I never knew the MM code was so dirty. "mm: ksm: prevent KSM from breaking merging of new VMAs" (Lorenzo Stoakes) addresses an issue with KSM's PR_SET_MEMORY_MERGE mode: newly mapped VMAs were not eligible for merging with existing adjacent VMAs. "mm/damon: introduce DAMON_STAT for simple and practical access monitoring" (SeongJae Park) adds a new kernel module which simplifies the setup and usage of DAMON in production environments. "stop passing a writeback_control to swap/shmem writeout" (Christoph Hellwig) is a cleanup to the writeback code which removes a couple of pointers from struct writeback_control. "drivers/base/node.c: optimization and cleanups" (Donet Tom) contains largely uncorrelated cleanups to the NUMA node setup and management code. "mm: userfaultfd: assorted fixes and cleanups" (Tal Zussman) does some maintenance work on the userfaultfd code. "Readahead tweaks for larger folios" (Ryan Roberts) implements some tuneups for pagecache readahead when it is reading into order>0 folios. "selftests/mm: Tweaks to the cow test" (Mark Brown) provides some cleanups and consistency improvements to the selftests code. "Optimize mremap() for large folios" (Dev Jain) does that. A 37% reduction in execution time was measured in a memset+mremap+munmap microbenchmark. "Remove zero_user()" (Matthew Wilcox) expunges zero_user() in favor of the more modern memzero_page(). "mm/huge_memory: vmf_insert_folio_*() and vmf_insert_pfn_pud() fixes" (David Hildenbrand) addresses some warts which David noticed in the huge page code. These were not known to be causing any issues at this time. "mm/damon: use alloc_migrate_target() for DAMOS_MIGRATE_{HOT,COLD" (SeongJae Park) provides some cleanup and consolidation work in DAMON. "use vm_flags_t consistently" (Lorenzo Stoakes) uses vm_flags_t in places where we were inappropriately using other types. "mm/memfd: Reserve hugetlb folios before allocation" (Vivek Kasireddy) increases the reliability of large page allocation in the memfd code. "mm: Remove pXX_devmap page table bit and pfn_t type" (Alistair Popple) removes several now-unneeded PFN_* flags. "mm/damon: decouple sysfs from core" (SeongJae Park) implememnts some cleanup and maintainability work in the DAMON sysfs layer. "madvise cleanup" (Lorenzo Stoakes) does quite a lot of cleanup/maintenance work in the madvise() code. "madvise anon_name cleanups" (Vlastimil Babka) provides additional cleanups on top or Lorenzo's effort. "Implement numa node notifier" (Oscar Salvador) creates a standalone notifier for NUMA node memory state changes. Previously these were lumped under the more general memory on/offline notifier. "Make MIGRATE_ISOLATE a standalone bit" (Zi Yan) cleans up the pageblock isolation code and fixes a potential issue which doesn't seem to cause any problems in practice. "selftests/damon: add python and drgn based DAMON sysfs functionality tests" (SeongJae Park) adds additional drgn- and python-based DAMON selftests which are more comprehensive than the existing selftest suite. "Misc rework on hugetlb faulting path" (Oscar Salvador) fixes a rather obscure deadlock in the hugetlb fault code and follows that fix with a series of cleanups. "cma: factor out allocation logic from __cma_declare_contiguous_nid" (Mike Rapoport) rationalizes and cleans up the highmem-specific code in the CMA allocator. "mm/migration: rework movable_ops page migration (part 1)" (David Hildenbrand) provides cleanups and future-preparedness to the migration code. "mm/damon: add trace events for auto-tuned monitoring intervals and DAMOS quota" (SeongJae Park) adds some tracepoints to some DAMON auto-tuning code. "mm/damon: fix misc bugs in DAMON modules" (SeongJae Park) does that. "mm/damon: misc cleanups" (SeongJae Park) also does what it claims. "mm: folio_pte_batch() improvements" (David Hildenbrand) cleans up the large folio PTE batching code. "mm/damon/vaddr: Allow interleaving in migrate_{hot,cold} actions" (SeongJae Park) facilitates dynamic alteration of DAMON's inter-node allocation policy. "Remove unmap_and_put_page()" (Vishal Moola) provides a couple of page->folio conversions. "mm: per-node proactive reclaim" (Davidlohr Bueso) implements a per-node control of proactive reclaim - beyond the current memcg-based implementation. "mm/damon: remove damon_callback" (SeongJae Park) replaces the damon_callback interface with a more general and powerful damon_call()+damos_walk() interface. "mm/mremap: permit mremap() move of multiple VMAs" (Lorenzo Stoakes) implements a number of mremap cleanups (of course) in preparation for adding new mremap() functionality: newly permit the remapping of multiple VMAs when the user is specifying MREMAP_FIXED. It still excludes some specialized situations where this cannot be performed reliably. "drop hugetlb_free_pgd_range()" (Anthony Yznaga) switches some sparc hugetlb code over to the generic version and removes the thus-unneeded hugetlb_free_pgd_range(). "mm/damon/sysfs: support periodic and automated stats update" (SeongJae Park) augments the present userspace-requested update of DAMON sysfs monitoring files. Automatic update is now provided, along with a tunable to control the update interval. "Some randome fixes and cleanups to swapfile" (Kemeng Shi) does what is claims. "mm: introduce snapshot_page" (Luiz Capitulino and David Hildenbrand) provides (and uses) a means by which debug-style functions can grab a copy of a pageframe and inspect it locklessly without tripping over the races inherent in operating on the live pageframe directly. "use per-vma locks for /proc/pid/maps reads" (Suren Baghdasaryan) addresses the large contention issues which can be triggered by reads from that procfs file. Latencies are reduced by more than half in some situations. The series also introduces several new selftests for the /proc/pid/maps interface. "__folio_split() clean up" (Zi Yan) cleans up __folio_split()! "Optimize mprotect() for large folios" (Dev Jain) provides some quite large (>3x) speedups to mprotect() when dealing with large folios. "selftests/mm: reuse FORCE_READ to replace "asm volatile("" : "+r" (XXX));" and some cleanup" (wang lian) does some cleanup work in the selftests code. "tools/testing: expand mremap testing" (Lorenzo Stoakes) extends the mremap() selftest in several ways, including adding more checking of Lorenzo's recently added "permit mremap() move of multiple VMAs" feature. "selftests/damon/sysfs.py: test all parameters" (SeongJae Park) extends the DAMON sysfs interface selftest so that it tests all possible user-requested parameters. Rather than the present minimal subset" * tag 'mm-stable-2025-07-30-15-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (370 commits) MAINTAINERS: add missing headers to mempory policy & migration section MAINTAINERS: add missing file to cgroup section MAINTAINERS: add MM MISC section, add missing files to MISC and CORE MAINTAINERS: add missing zsmalloc file MAINTAINERS: add missing files to page alloc section MAINTAINERS: add missing shrinker files MAINTAINERS: move memremap.[ch] to hotplug section MAINTAINERS: add missing mm_slot.h file THP section MAINTAINERS: add missing interval_tree.c to memory mapping section MAINTAINERS: add missing percpu-internal.h file to per-cpu section mm/page_alloc: remove trace_mm_alloc_contig_migrate_range_info() selftests/damon: introduce _common.sh to host shared function selftests/damon/sysfs.py: test runtime reduction of DAMON parameters selftests/damon/sysfs.py: test non-default parameters runtime commit selftests/damon/sysfs.py: generalize DAMON context commit assertion selftests/damon/sysfs.py: generalize monitoring attributes commit assertion selftests/damon/sysfs.py: generalize DAMOS schemes commit assertion selftests/damon/sysfs.py: test DAMOS filters commitment selftests/damon/sysfs.py: generalize DAMOS scheme commit assertion selftests/damon/sysfs.py: test DAMOS destinations commitment ...
2025-07-31Merge tag 'docs-6.17' of git://git.lwn.net/linuxLinus Torvalds
Pull documentation updates from Jonathan Corbet: "It has been a relatively busy cycle for docs, especially the build system: - The Perl kernel-doc script was added to 2.3.52pre1 just after the turn of the millennium. Over the following 25 years, it accumulated a vast amount of cruft, all in a language few people want to deal with anymore. Mauro's Python replacement in 6.16 faithfully reproduced all of the cruft in the hope of avoiding regressions. Now that we have a more reasonable code base, though, we can work on cleaning it up; many of the changes this time around are toward that end. - A reorganization of the ext4 docs into the usual TOC format. - Various Chinese translations and updates. - A new script from Mauro to help with docs-build testing. - A new document for linked lists - A sweep through MAINTAINERS fixing broken GitHub git:// repository links. ...and lots of fixes and updates" * tag 'docs-6.17' of git://git.lwn.net/linux: (147 commits) scripts: add origin commit identification based on specific patterns sphinx: kernel_abi: fix performance regression with O=<dir> Documentation: core-api: entry: Replace deprecated KVM entry/exit functions docs: fault-injection: drop reference to md-faulty docs: document linked lists scripts: kdoc: make it backward-compatible with Python 3.7 docs: kernel-doc: emit warnings for ancient versions of Python Documentation/rtla: Describe exit status Documentation/rtla: Add include common_appendix.rst docs: kernel: Clarify printk_ratelimit_burst reset behavior Documentation: ioctl-number: Don't repeat macro names Documentation: ioctl-number: Shorten macros table Documentation: ioctl-number: Correct full path to papr-physical-attestation.h Documentation: ioctl-number: Extend "Include File" column width Documentation: ioctl-number: Fix linuxppc-dev mailto link overlayfs.rst: fix typos docs: kdoc: emit a warning for ancient versions of Python docs: kdoc: clean up check_sections() docs: kdoc: directly access the always-there KdocItem fields docs: kdoc: straighten up dump_declaration() ...
2025-07-28Merge tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linuxLinus Torvalds
Pull fscrypt updates from Eric Biggers: "Simplify how fscrypt uses the crypto API, resulting in some significant performance improvements: - Drop the incomplete and problematic support for asynchronous algorithms. These drivers are bug-prone, and it turns out they are actually much slower than the CPU-based code as well. - Allocate crypto requests on the stack instead of the heap. This improves encryption and decryption performance, especially for filenames. This also eliminates a point of failure during I/O" * tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/linux: ceph: Remove gfp_t argument from ceph_fscrypt_encrypt_*() fscrypt: Remove gfp_t argument from fscrypt_encrypt_block_inplace() fscrypt: Remove gfp_t argument from fscrypt_crypt_data_unit() fscrypt: Switch to sync_skcipher and on-stack requests fscrypt: Drop FORBID_WEAK_KEYS flag for AES-ECB fscrypt: Don't use asynchronous CryptoAPI algorithms fscrypt: Don't use problematic non-inline crypto engines fscrypt: Drop obsolete recommendation to enable optimized SHA-512 fscrypt: Explicitly include <linux/export.h>
2025-07-28Merge tag 'libcrypto-conversions-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux Pull crypto library conversions from Eric Biggers: "Convert fsverity and apparmor to use the SHA-2 library functions instead of crypto_shash. This is simpler and also slightly faster" * tag 'libcrypto-conversions-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiggers/linux: fsverity: Switch from crypto_shash to SHA-2 library fsverity: Explicitly include <linux/export.h> apparmor: use SHA-256 library API instead of crypto_shash API
2025-07-28Merge tag 'vfs-6.17-rc1.iomap' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull vfs iomap updates from Christian Brauner: - Refactor the iomap writeback code and split the generic and ioend/bio based writeback code. There are two methods that define the split between the generic writeback code, and the implemementation of it, and all knowledge of ioends and bios now sits below that layer. - Add fuse iomap support for buffered writes and dirty folio writeback. This is needed so that granular uptodate and dirty tracking can be used in fuse when large folios are enabled. This has two big advantages. For writes, instead of the entire folio needing to be read into the page cache, only the relevant portions need to be. For writeback, only the dirty portions need to be written back instead of the entire folio. * tag 'vfs-6.17-rc1.iomap' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fuse: refactor writeback to use iomap_writepage_ctx inode fuse: hook into iomap for invalidating and checking partial uptodateness fuse: use iomap for folio laundering fuse: use iomap for writeback fuse: use iomap for buffered writes iomap: build the writeback code without CONFIG_BLOCK iomap: add read_folio_range() handler for buffered writes iomap: improve argument passing to iomap_read_folio_sync iomap: replace iomap_folio_ops with iomap_write_ops iomap: export iomap_writeback_folio iomap: move folio_unlock out of iomap_writeback_folio iomap: rename iomap_writepage_map to iomap_writeback_folio iomap: move all ioend handling to ioend.c iomap: add public helpers for uptodate state manipulation iomap: hide ioends from the generic writeback code iomap: refactor the writeback interface iomap: cleanup the pending writeback tracking in iomap_writepage_map_blocks iomap: pass more arguments using the iomap writeback context iomap: header diet
2025-07-28Merge tag 'vfs-6.17-rc1.fileattr' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull fileattr updates from Christian Brauner: "This introduces the new file_getattr() and file_setattr() system calls after lengthy discussions. Both system calls serve as successors and extensible companions to the FS_IOC_FSGETXATTR and FS_IOC_FSSETXATTR system calls which have started to show their age in addition to being named in a way that makes it easy to conflate them with extended attribute related operations. These syscalls allow userspace to set filesystem inode attributes on special files. One of the usage examples is the XFS quota projects. XFS has project quotas which could be attached to a directory. All new inodes in these directories inherit project ID set on parent directory. The project is created from userspace by opening and calling FS_IOC_FSSETXATTR on each inode. This is not possible for special files such as FIFO, SOCK, BLK etc. Therefore, some inodes are left with empty project ID. Those inodes then are not shown in the quota accounting but still exist in the directory. This is not critical but in the case when special files are created in the directory with already existing project quota, these new inodes inherit extended attributes. This creates a mix of special files with and without attributes. Moreover, special files with attributes don't have a possibility to become clear or change the attributes. This, in turn, prevents userspace from re-creating quota project on these existing files. In addition, these new system calls allow the implementation of additional attributes that we couldn't or didn't want to fit into the legacy ioctls anymore" * tag 'vfs-6.17-rc1.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: fs: tighten a sanity check in file_attr_to_fileattr() tree-wide: s/struct fileattr/struct file_kattr/g fs: introduce file_getattr and file_setattr syscalls fs: prepare for extending file_get/setattr() fs: make vfs_fileattr_[get|set] return -EOPNOTSUPP selinux: implement inode_file_[g|s]etattr hooks lsm: introduce new hooks for setting/getting inode fsxattr fs: split fileattr related helpers into separate file
2025-07-28Merge tag 'vfs-6.17-rc1.mmap_prepare' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull mmap_prepare updates from Christian Brauner: "Last cycle we introduce f_op->mmap_prepare() in c84bf6dd2b83 ("mm: introduce new .mmap_prepare() file callback"). This is preferred to the existing f_op->mmap() hook as it does require a VMA to be established yet, thus allowing the mmap logic to invoke this hook far, far earlier, prior to inserting a VMA into the virtual address space, or performing any other heavy handed operations. This allows for much simpler unwinding on error, and for there to be a single attempt at merging a VMA rather than having to possibly reattempt a merge based on potentially altered VMA state. Far more importantly, it prevents inappropriate manipulation of incompletely initialised VMA state, which is something that has been the cause of bugs and complexity in the past. The intent is to gradually deprecate f_op->mmap, and in that vein this series coverts the majority of file systems to using f_op->mmap_prepare. Prerequisite steps are taken - firstly ensuring all checks for mmap capabilities use the file_has_valid_mmap_hooks() helper rather than directly checking for f_op->mmap (which is now not a valid check) and secondly updating daxdev_mapping_supported() to not require a VMA parameter to allow ext4 and xfs to be converted. Commit bb666b7c2707 ("mm: add mmap_prepare() compatibility layer for nested file systems") handles the nasty edge-case of nested file systems like overlayfs, which introduces a compatibility shim to allow f_op->mmap_prepare() to be invoked from an f_op->mmap() callback. This allows for nested filesystems to continue to function correctly with all file systems regardless of which callback is used. Once we finally convert all file systems, this shim can be removed. As a result, ecryptfs, fuse, and overlayfs remain unaltered so they can nest all other file systems. We additionally do not update resctl - as this requires an update to remap_pfn_range() (or an alternative to it) which we defer to a later series, equally we do not update cramfs which needs a mixed mapping insertion with the same issue, nor do we update procfs, hugetlbfs, syfs or kernfs all of which require VMAs for internal state and hooks. We shall return to all of these later" * tag 'vfs-6.17-rc1.mmap_prepare' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: doc: update porting, vfs documentation to describe mmap_prepare() fs: replace mmap hook with .mmap_prepare for simple mappings fs: convert most other generic_file_*mmap() users to .mmap_prepare() fs: convert simple use of generic_file_*_mmap() to .mmap_prepare() mm/filemap: introduce generic_file_*_mmap_prepare() helpers fs/xfs: transition from deprecated .mmap hook to .mmap_prepare fs/ext4: transition from deprecated .mmap hook to .mmap_prepare fs/dax: make it possible to check dev dax support without a VMA fs: consistently use can_mmap_file() helper mm/nommu: use file_has_valid_mmap_hooks() helper mm: rename call_mmap/mmap_prepare to vfs_mmap/mmap_prepare
2025-07-28Merge tag 'vfs-6.17-rc1.async.dir' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull async directory updates from Christian Brauner: "This contains preparatory changes for the asynchronous directory locking scheme. While the locking scheme is still very much controversial and we're still far away from landing any actual changes in that area the preparatory work that we've been upstreaming for a while now has been very useful. This is another set of minor changes and cleanups" * tag 'vfs-6.17-rc1.async.dir' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: exportfs: use lookup_one_unlocked() coda: use iterate_dir() in coda_readdir() VFS: Minor fixes for porting.rst VFS: merge lookup_one_qstr_excl_raw() back into lookup_one_qstr_excl()
2025-07-28Merge tag 'vfs-6.17-rc1.misc' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull misc VFS updates from Christian Brauner: "This contains the usual selections of misc updates for this cycle. Features: - Add ext4 IOCB_DONTCACHE support This refactors the address_space_operations write_begin() and write_end() callbacks to take const struct kiocb * as their first argument, allowing IOCB flags such as IOCB_DONTCACHE to propagate to the filesystem's buffered I/O path. Ext4 is updated to implement handling of the IOCB_DONTCACHE flag and advertises support via the FOP_DONTCACHE file operation flag. Additionally, the i915 driver's shmem write paths are updated to bypass the legacy write_begin/write_end interface in favor of directly calling write_iter() with a constructed synchronous kiocb. Another i915 change replaces a manual write loop with kernel_write() during GEM shmem object creation. Cleanups: - don't duplicate vfs_open() in kernel_file_open() - proc_fd_getattr(): don't bother with S_ISDIR() check - fs/ecryptfs: replace snprintf with sysfs_emit in show function - vfs: Remove unnecessary list_for_each_entry_safe() from evict_inodes() - filelock: add new locks_wake_up_waiter() helper - fs: Remove three arguments from block_write_end() - VFS: change old_dir and new_dir in struct renamedata to dentrys - netfs: Remove unused declaration netfs_queue_write_request() Fixes: - eventpoll: Fix semi-unbounded recursion - eventpoll: fix sphinx documentation build warning - fs/read_write: Fix spelling typo - fs: annotate data race between poll_schedule_timeout() and pollwake() - fs/pipe: set FMODE_NOWAIT in create_pipe_files() - docs/vfs: update references to i_mutex to i_rwsem - fs/buffer: remove comment about hard sectorsize - fs/buffer: remove the min and max limit checks in __getblk_slow() - fs/libfs: don't assume blocksize <= PAGE_SIZE in generic_check_addressable - fs_context: fix parameter name in infofc() macro - fs: Prevent file descriptor table allocations exceeding INT_MAX" * tag 'vfs-6.17-rc1.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (24 commits) netfs: Remove unused declaration netfs_queue_write_request() eventpoll: fix sphinx documentation build warning ext4: support uncached buffered I/O mm/pagemap: add write_begin_get_folio() helper function fs: change write_begin/write_end interface to take struct kiocb * drm/i915: Refactor shmem_pwrite() to use kiocb and write_iter drm/i915: Use kernel_write() in shmem object create eventpoll: Fix semi-unbounded recursion vfs: Remove unnecessary list_for_each_entry_safe() from evict_inodes() fs/libfs: don't assume blocksize <= PAGE_SIZE in generic_check_addressable fs/buffer: remove the min and max limit checks in __getblk_slow() fs: Prevent file descriptor table allocations exceeding INT_MAX fs: Remove three arguments from block_write_end() fs/ecryptfs: replace snprintf with sysfs_emit in show function fs: annotate suspected data race between poll_schedule_timeout() and pollwake() docs/vfs: update references to i_mutex to i_rwsem fs/buffer: remove comment about hard sectorsize fs_context: fix parameter name in infofc() macro VFS: change old_dir and new_dir in struct renamedata to dentrys proc_fd_getattr(): don't bother with S_ISDIR() check ...
2025-07-28Merge tag 'pull-mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfsLinus Torvalds
Pull vfs mount updates from Al Viro: - mount hash conflicts rudiments are gone now - we do not allow multiple mounts with the same parent/mountpoint to be hashed at the same time. - 'struct mount' changes: - mnt_umounting is gone - mnt_slave_list/mnt_slave is an hlist now - overmounts are kept track of by explicit pointer in mount - a bunch of flags moved out of mnt_flags to a new field, with only namespace_sem for protection - mnt_expiry is protected by mount_lock now (instead of namespace_sem) - MNT_LOCKED is used only for mounts that need to remain attached to their parents to prevent mountpoint exposure - no more overloading it for absolute roots - all mnt_list uses are transient now - it's used only to represent temporary sets during umount_tree() - mount refcounting change: children no longer pin parents for any mounts, whether they'd passed through umount_tree() or not - 'struct mountpoint' changes: - refcount is no more; what matters is ->m_list emptiness - instead of temporary bumping the refcount, we insert a new object (pinned_mountpoint) into ->m_list - new calling conventions for lock_mount() and friends - do_move_mount()/attach_recursive_mnt() seriously cleaned up - globals in fs/pnode.c are gone - propagate_mnt(), change_mnt_propagation() and propagate_umount() cleaned up (in the last case - pretty much completely rewritten). - freeing of emptied mnt_namespace is done in namespace_unlock(). For one thing, there are subtle ordering requirements there; for another it simplifies cleanups. - assorted cleanups - restore the machinery for long-term mounts from accumulated bitrot. This is going to get a followup come next cycle, when the change of vfs_fs_parse_string() calling conventions goes into -next * tag 'pull-mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (48 commits) statmount_mnt_basic(): simplify the logics for group id invent_group_ids(): zero ->mnt_group_id always implies !IS_MNT_SHARED() get rid of CL_SHARE_TO_SLAVE take freeing of emptied mnt_namespace to namespace_unlock() copy_tree(): don't link the mounts via mnt_list change_mnt_propagation(): move ->mnt_master assignment into MS_SLAVE case mnt_slave_list/mnt_slave: turn into hlist_head/hlist_node turn do_make_slave() into transfer_propagation() do_make_slave(): choose new master sanely change_mnt_propagation(): do_make_slave() is a no-op unless IS_MNT_SHARED() change_mnt_propagation() cleanups, step 1 propagate_mnt(): fix comment and convert to kernel-doc, while we are at it propagate_mnt(): get rid of last_dest fs/pnode.c: get rid of globals propagate_one(): fold into the sole caller propagate_one(): separate the "what should be the master for this copy" part propagate_one(): separate the "do we need secondary here?" logics propagate_mnt(): handle all peer groups in the same loop propagate_one(): get rid of dest_master mount: separate the flags accessed only under namespace_sem ...
2025-07-28Merge tag 'pull-dcache' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull dentry d_flags updates from Al Viro: "The current exclusion rules for dentry->d_flags stores are rather unpleasant. The basic rules are simple: - stores to dentry->d_flags are OK under dentry->d_lock - stores to dentry->d_flags are OK in the dentry constructor, before becomes potentially visible to other threads Unfortunately, there's a couple of exceptions to that, and that's where the headache comes from. The main PITA comes from d_set_d_op(); that primitive sets ->d_op of dentry and adjusts the flags that correspond to presence of individual methods. It's very easy to misuse; existing uses _are_ safe, but proof of correctness is brittle. Use in __d_alloc() is safe (we are within a constructor), but we might as well precalculate the initial value of 'd_flags' when we set the default ->d_op for given superblock and set 'd_flags' directly instead of messing with that helper. The reasons why other uses are safe are bloody convoluted; I'm not going to reproduce it here. See [1] for gory details, if you care. The critical part is using d_set_d_op() only just prior to d_splice_alias(), which makes a combination of d_splice_alias() with setting ->d_op, etc a natural replacement primitive. Better yet, if we go that way, it's easy to take setting ->d_op and modifying 'd_flags' under ->d_lock, which eliminates the headache as far as 'd_flags' exclusion rules are concerned. Other exceptions are minor and easy to deal with. What this series does: - d_set_d_op() is no longer available; instead a new primitive (d_splice_alias_ops()) is provided, equivalent to combination of d_set_d_op() and d_splice_alias(). - new field of struct super_block - 's_d_flags'. This sets the default value of 'd_flags' to be used when allocating dentries on this filesystem. - new primitive for setting 's_d_op': set_default_d_op(). This replaces stores to 's_d_op' at mount time. All in-tree filesystems converted; out-of-tree ones will get caught by the compiler ('s_d_op' is renamed, so stores to it will be caught). 's_d_flags' is set by the same primitive to match the 's_d_op'. - a lot of filesystems had sb->s_d_op->d_delete equal to always_delete_dentry; that is equivalent to setting DCACHE_DONTCACHE in 'd_flags', so such filesystems can bloody well set that bit in 's_d_flags' and drop 'd_delete()' from dentry_operations. In quite a few cases that results in empty dentry_operations, which means that we can get rid of those. - kill simple_dentry_operations - not needed anymore - massage d_alloc_parallel() to get rid of the other exception wrt 'd_flags' stores - we can set DCACHE_PAR_LOOKUP as soon as we allocate the new dentry; no need to delay that until we commit to using the sucker. As the result, 'd_flags' stores are all either under ->d_lock or done before the dentry becomes visible in any shared data structures" Link: https://lore.kernel.org/all/20250224010624.GT1977892@ZenIV/ [1] * tag 'pull-dcache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (21 commits) configfs: use DCACHE_DONTCACHE debugfs: use DCACHE_DONTCACHE efivarfs: use DCACHE_DONTCACHE instead of always_delete_dentry() 9p: don't bother with always_delete_dentry ramfs, hugetlbfs, mqueue: set DCACHE_DONTCACHE kill simple_dentry_operations devpts, sunrpc, hostfs: don't bother with ->d_op shmem: no dentry retention past the refcount reaching zero d_alloc_parallel(): set DCACHE_PAR_LOOKUP earlier make d_set_d_op() static simple_lookup(): just set DCACHE_DONTCACHE tracefs: Add d_delete to remove negative dentries set_default_d_op(): calculate the matching value for ->d_flags correct the set of flags forbidden at d_set_d_op() time split d_flags calculation out of d_set_d_op() new helper: set_default_d_op() fuse: no need for special dentry_operations for root dentry switch procfs from d_set_d_op() to d_splice_alias_ops() new helper: d_splice_alias_ops() procfs: kill ->proc_dops ...
2025-07-23doc: update porting, vfs documentation to describe mmap_prepare()Lorenzo Stoakes
Now that we have established .mmap_prepare() as the preferred means by which filesystems establish state upon memory mapping of a file, update the VFS and porting documentation to reflect this. As part of this change, additionally update the VFS documentation to contain the current state of the file_operations struct. Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Link: https://lore.kernel.org/20250723123036.35472-1-lorenzo.stoakes@oracle.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-19mm, vmstat: remove the NR_WRITEBACK_TEMP node_stat_item counterVlastimil Babka
The only user of the counter (FUSE) was removed in commit 0c58a97f919c ("fuse: remove tmp folio for writebacks and internal rb tree") so follow the established pattern of removing the counter and hardcoding 0 in meminfo output, as done recently with NR_BOUNCE. Update documentation for procfs, including for the value for Bounce that was missed when removing its counter. Also remove the mention of NR_WRITEBACK_TEMP implications from a comment in wb_position_ratio(). The rest of the comment there about fuse setting bdi->max_ratio to 1% is still correct. [vbabka@suse.cz: v2] Link: https://lkml.kernel.org/r/5a848e15-6a57-4ecb-a015-d4f358b8a5d3@suse.cz Link: https://lkml.kernel.org/r/20250625-nr_writeback_removal-v1-1-7f2a0df70faa@suse.cz Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Cc: Brendan Jackman <jackmanb@google.com> Cc: Danilo Krummrich <dakr@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jan Kara <jack@suse.cz> Cc: Jeff Layton <jlayton@kernel.org> Cc: Jeffle Xu <jefflexu@linux.alibaba.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joanne Koong <joannelkoong@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kirill A. Shuemov <kirill.shutemov@linux.intel.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Maxim Patlasov <mpatlasov@parallels.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Miklos Szeredi <mszeredi@redhat.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Zach O'Keefe <zokeefe@google.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-07-16fs: change write_begin/write_end interface to take struct kiocb *Taotao Chen
Change the address_space_operations callbacks write_begin() and write_end() to take struct kiocb * as the first argument instead of struct file *. Update all affected function prototypes, implementations, call sites, and related documentation across VFS, filesystems, and block layer. Part of a series refactoring address_space_operations write_begin and write_end callbacks to use struct kiocb for passing write context and flags. Signed-off-by: Taotao Chen <chentaotao@didiglobal.com> Link: https://lore.kernel.org/20250716093559.217344-4-chentaotao@didiglobal.com Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-15overlayfs.rst: fix typosMatthias Frank
Grammatical fixes Signed-off-by: Matthias Frank <frank.mt125@gmail.com> Acked-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250710050607.2891-1-frank.mt125@gmail.com
2025-07-14fsverity: Switch from crypto_shash to SHA-2 libraryEric Biggers
fsverity supports two hash algorithms: SHA-256 and SHA-512. Since both of these have a library API now, just use the library API instead of crypto_shash. Even with multiple algorithms, the library-based code still ends up being quite a bit simpler, due to how clumsy the old-school crypto API is. The library-based code is also more efficient, since it avoids overheads such as indirect calls. Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250630172224.46909-3-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-14iomap: add read_folio_range() handler for buffered writesChristoph Hellwig
Add a read_folio_range() handler for buffered writes that filesystems may pass in if they wish to provide a custom handler for synchronously reading in the contents of a folio. Signed-off-by: Joanne Koong <joannelkoong@gmail.com> [hch: renamed to read_folio_range, pass less arguments] Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-14-hch@lst.de Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: replace iomap_folio_ops with iomap_write_opsChristoph Hellwig
The iomap_folio_ops are only used for buffered writes, including the zero and unshare variants. Rename them to iomap_write_ops to better describe the usage, and pass them through the call chain like the other operation specific methods instead of through the iomap. xfs_iomap_valid grows a IOMAP_HOLE check to keep the existing behavior that never attached the folio_ops to a iomap representing a hole. Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-12-hch@lst.de Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: hide ioends from the generic writeback codeChristoph Hellwig
Replace the ioend pointer in iomap_writeback_ctx with a void *wb_ctx one to facilitate non-block, non-ioend writeback for use. Rename the submit_ioend method to writeback_submit and make it mandatory so that the generic writeback code stops seeing ioends and bios. Co-developed-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-6-hch@lst.de Acked-by: Damien Le Moal <dlemoal@kernel.org> Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-14iomap: refactor the writeback interfaceChristoph Hellwig
Replace ->map_blocks with a new ->writeback_range, which differs in the following ways: - it must also queue up the I/O for writeback, that is called into the slightly refactored and extended in scope iomap_add_to_ioend for each region - can handle only a part of the requested region, that is the retry loop for partial mappings moves to the caller - handles cleanup on failures as well, and thus also replaces the discard_folio method only implemented by XFS. This will allow to use the iomap writeback code also for file systems that are not block based like fuse. Co-developed-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Joanne Koong <joannelkoong@gmail.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Link: https://lore.kernel.org/20250710133343.399917-5-hch@lst.de Acked-by: Damien Le Moal <dlemoal@kernel.org> # zonefs Reviewed-by: Brian Foster <bfoster@redhat.com> Reviewed-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-09f2fs: doc: fix wrong quota mount option descriptionChao Yu
We should use "{usr,grp,prj}jquota=" to disable journaled quota, rather than using off{usr,grp,prj}jquota. Fixes: 4b2414d04e99 ("f2fs: support journalled quota") Signed-off-by: Chao Yu <chao@kernel.org> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
2025-07-04fscrypt: Don't use problematic non-inline crypto enginesEric Biggers
Make fscrypt no longer use Crypto API drivers for non-inline crypto engines, even when the Crypto API prioritizes them over CPU-based code (which unfortunately it often does). These drivers tend to be really problematic, especially for fscrypt's workload. This commit has no effect on inline crypto engines, which are different and do work well. Specifically, exclude drivers that have CRYPTO_ALG_KERN_DRIVER_ONLY or CRYPTO_ALG_ALLOCATES_MEMORY set. (Later, CRYPTO_ALG_ASYNC should be excluded too. That's omitted for now to keep this commit backportable, since until recently some CPU-based code had CRYPTO_ALG_ASYNC set.) There are two major issues with these drivers: bugs and performance. First, these drivers tend to be buggy. They're fundamentally much more error-prone and harder to test than the CPU-based code. They often don't get tested before kernel releases, and even if they do, the crypto self-tests don't properly test these drivers. Released drivers have en/decrypted or hashed data incorrectly. These bugs cause issues for fscrypt users who often didn't even want to use these drivers, e.g.: - https://github.com/google/fscryptctl/issues/32 - https://github.com/google/fscryptctl/issues/9 - https://lore.kernel.org/r/PH0PR02MB731916ECDB6C613665863B6CFFAA2@PH0PR02MB7319.namprd02.prod.outlook.com These drivers have also similarly caused issues for dm-crypt users, including data corruption and deadlocks. Since Linux v5.10, dm-crypt has disabled most of them by excluding CRYPTO_ALG_ALLOCATES_MEMORY. Second, these drivers tend to be *much* slower than the CPU-based code. This may seem counterintuitive, but benchmarks clearly show it. There's a *lot* of overhead associated with going to a hardware driver, off the CPU, and back again. To prove this, I gathered as many systems with this type of crypto engine as I could, and I measured synchronous encryption of 4096-byte messages (which matches fscrypt's workload): Intel Emerald Rapids server: AES-256-XTS: xts-aes-vaes-avx512 16171 MB/s [CPU-based, Vector AES] qat_aes_xts 289 MB/s [Offload, Intel QuickAssist] Qualcomm SM8650 HDK: AES-256-XTS: xts-aes-ce 4301 MB/s [CPU-based, ARMv8 Crypto Extensions] xts-aes-qce 73 MB/s [Offload, Qualcomm Crypto Engine] i.MX 8M Nano LPDDR4 EVK: AES-256-XTS: xts-aes-ce 647 MB/s [CPU-based, ARMv8 Crypto Extensions] xts(ecb-aes-caam) 20 MB/s [Offload, CAAM] AES-128-CBC-ESSIV: essiv(cbc-aes-caam,sha256-lib) 23 MB/s [Offload, CAAM] STM32MP157F-DK2: AES-256-XTS: xts-aes-neonbs 13.2 MB/s [CPU-based, ARM NEON] xts(stm32-ecb-aes) 3.1 MB/s [Offload, STM32 crypto engine] AES-128-CBC-ESSIV: essiv(cbc-aes-neonbs,sha256-lib) 14.7 MB/s [CPU-based, ARM NEON] essiv(stm32-cbc-aes,sha256-lib) 3.2 MB/s [Offload, STM32 crypto engine] Adiantum: adiantum(xchacha12-arm,aes-arm,nhpoly1305-neon) 52.8 MB/s [CPU-based, ARM scalar + NEON] So, there was no case in which the crypto engine was even *close* to being faster. On the first three, which have AES instructions in the CPU, the CPU was 30 to 55 times faster (!). Even on STM32MP157F-DK2 which has a Cortex-A7 CPU that doesn't have AES instructions, AES was over 4 times faster on the CPU. And Adiantum encryption, which is what actually should be used on CPUs like that, was over 17 times faster. Other justifications that have been given for these non-inline crypto engines (almost always coming from the hardware vendors, not actual users) don't seem very plausible either: - The crypto engine throughput could be improved by processing multiple requests concurrently. Currently irrelevant to fscrypt, since it doesn't do that. This would also be complex, and unhelpful in many cases. 2 of the 4 engines I tested even had only one queue. - Some of the engines, e.g. STM32, support hardware keys. Also currently irrelevant to fscrypt, since it doesn't support these. Interestingly, the STM32 driver itself doesn't support this either. - Free up CPU for other tasks and/or reduce energy usage. Not very plausible considering the "short" message length, driver overhead, and scheduling overhead. There's just very little time for the CPU to do something else like run another task or enter low-power state, before the message finishes and it's time to process the next one. - Some of these engines resist power analysis and electromagnetic attacks, while the CPU-based crypto generally does not. In theory, this sounds great. In practice, if this benefit requires the use of an off-CPU offload that massively regresses performance and has a low-quality, buggy driver, the price for this hardening (which is not relevant to most fscrypt users, and tends to be incomplete) is just too high. Inline crypto engines are much more promising here, as are on-CPU solutions like RISC-V High Assurance Cryptography. Fixes: b30ab0e03407 ("ext4 crypto: add ext4 encryption facilities") Cc: stable@vger.kernel.org Acked-by: Ard Biesheuvel <ardb@kernel.org> Link: https://lore.kernel.org/r/20250704070322.20692-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-04tree-wide: s/struct fileattr/struct file_kattr/gChristian Brauner
Now that we expose struct file_attr as our uapi struct rename all the internal struct to struct file_kattr to clearly communicate that it is a kernel internal struct. This is similar to struct mount_{k}attr and others. Link: https://lore.kernel.org/20250703-restlaufzeit-baurecht-9ed44552b481@brauner Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-07-04fscrypt: Drop obsolete recommendation to enable optimized SHA-512Eric Biggers
Since the crypto kconfig options are being fixed to enable optimized SHA-512 automatically (https://lore.kernel.org/linux-crypto/20250616014019.415791-1-ebiggers@kernel.org/), it is no longer necessary to give a recommendation to enable it. Link: https://lore.kernel.org/r/20250619193149.138315-1-ebiggers@kernel.org Signed-off-by: Eric Biggers <ebiggers@kernel.org>
2025-07-02Documentation: ext4: Move inode table short docs into its own fileBagas Sanjaya
The short description of inode table is in bitmaps.rst alongside the proper bitmpas documentation. The docs file is short enough that it fits whole browser screen on desktop, which implies that when readers click "Inode Table", they will essentially see bitmaps docs. Move inode table short description. Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com> Acked-by: Theodore Ts'o <tytso@mit.edu> Acked-by: Darrick J. Wong <djwong@kernel.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net> Link: https://lore.kernel.org/r/20250620105643.25141-7-bagasdotme@gmail.com