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2023-11-02Merge tag 'mm-stable-2023-11-01-14-33' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: "Many singleton patches against the MM code. The patch series which are included in this merge do the following: - Kemeng Shi has contributed some compation maintenance work in the series 'Fixes and cleanups to compaction' - Joel Fernandes has a patchset ('Optimize mremap during mutual alignment within PMD') which fixes an obscure issue with mremap()'s pagetable handling during a subsequent exec(), based upon an implementation which Linus suggested - More DAMON/DAMOS maintenance and feature work from SeongJae Park i the following patch series: mm/damon: misc fixups for documents, comments and its tracepoint mm/damon: add a tracepoint for damos apply target regions mm/damon: provide pseudo-moving sum based access rate mm/damon: implement DAMOS apply intervals mm/damon/core-test: Fix memory leaks in core-test mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval - In the series 'Do not try to access unaccepted memory' Adrian Hunter provides some fixups for the recently-added 'unaccepted memory' feature. To increase the feature's checking coverage. 'Plug a few gaps where RAM is exposed without checking if it is unaccepted memory' - In the series 'cleanups for lockless slab shrink' Qi Zheng has done some maintenance work which is preparation for the lockless slab shrinking code - Qi Zheng has redone the earlier (and reverted) attempt to make slab shrinking lockless in the series 'use refcount+RCU method to implement lockless slab shrink' - David Hildenbrand contributes some maintenance work for the rmap code in the series 'Anon rmap cleanups' - Kefeng Wang does more folio conversions and some maintenance work in the migration code. Series 'mm: migrate: more folio conversion and unification' - Matthew Wilcox has fixed an issue in the buffer_head code which was causing long stalls under some heavy memory/IO loads. Some cleanups were added on the way. Series 'Add and use bdev_getblk()' - In the series 'Use nth_page() in place of direct struct page manipulation' Zi Yan has fixed a potential issue with the direct manipulation of hugetlb page frames - In the series 'mm: hugetlb: Skip initialization of gigantic tail struct pages if freed by HVO' has improved our handling of gigantic pages in the hugetlb vmmemmep optimizaton code. This provides significant boot time improvements when significant amounts of gigantic pages are in use - Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code rationalization and folio conversions in the hugetlb code - Yin Fengwei has improved mlock()'s handling of large folios in the series 'support large folio for mlock' - In the series 'Expose swapcache stat for memcg v1' Liu Shixin has added statistics for memcg v1 users which are available (and useful) under memcg v2 - Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable) prctl so that userspace may direct the kernel to not automatically propagate the denial to child processes. The series is named 'MDWE without inheritance' - Kefeng Wang has provided the series 'mm: convert numa balancing functions to use a folio' which does what it says - In the series 'mm/ksm: add fork-exec support for prctl' Stefan Roesch makes is possible for a process to propagate KSM treatment across exec() - Huang Ying has enhanced memory tiering's calculation of memory distances. This is used to permit the dax/kmem driver to use 'high bandwidth memory' in addition to Optane Data Center Persistent Memory Modules (DCPMM). The series is named 'memory tiering: calculate abstract distance based on ACPI HMAT' - In the series 'Smart scanning mode for KSM' Stefan Roesch has optimized KSM by teaching it to retain and use some historical information from previous scans - Yosry Ahmed has fixed some inconsistencies in memcg statistics in the series 'mm: memcg: fix tracking of pending stats updates values' - In the series 'Implement IOCTL to get and optionally clear info about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap which permits us to atomically read-then-clear page softdirty state. This is mainly used by CRIU - Hugh Dickins contributed the series 'shmem,tmpfs: general maintenance', a bunch of relatively minor maintenance tweaks to this code - Matthew Wilcox has increased the use of the VMA lock over file-backed page faults in the series 'Handle more faults under the VMA lock'. Some rationalizations of the fault path became possible as a result - In the series 'mm/rmap: convert page_move_anon_rmap() to folio_move_anon_rmap()' David Hildenbrand has implemented some cleanups and folio conversions - In the series 'various improvements to the GUP interface' Lorenzo Stoakes has simplified and improved the GUP interface with an eye to providing groundwork for future improvements - Andrey Konovalov has sent along the series 'kasan: assorted fixes and improvements' which does those things - Some page allocator maintenance work from Kemeng Shi in the series 'Two minor cleanups to break_down_buddy_pages' - In thes series 'New selftest for mm' Breno Leitao has developed another MM self test which tickles a race we had between madvise() and page faults - In the series 'Add folio_end_read' Matthew Wilcox provides cleanups and an optimization to the core pagecache code - Nhat Pham has added memcg accounting for hugetlb memory in the series 'hugetlb memcg accounting' - Cleanups and rationalizations to the pagemap code from Lorenzo Stoakes, in the series 'Abstract vma_merge() and split_vma()' - Audra Mitchell has fixed issues in the procfs page_owner code's new timestamping feature which was causing some misbehaviours. In the series 'Fix page_owner's use of free timestamps' - Lorenzo Stoakes has fixed the handling of new mappings of sealed files in the series 'permit write-sealed memfd read-only shared mappings' - Mike Kravetz has optimized the hugetlb vmemmap optimization in the series 'Batch hugetlb vmemmap modification operations' - Some buffer_head folio conversions and cleanups from Matthew Wilcox in the series 'Finish the create_empty_buffers() transition' - As a page allocator performance optimization Huang Ying has added automatic tuning to the allocator's per-cpu-pages feature, in the series 'mm: PCP high auto-tuning' - Roman Gushchin has contributed the patchset 'mm: improve performance of accounted kernel memory allocations' which improves their performance by ~30% as measured by a micro-benchmark - folio conversions from Kefeng Wang in the series 'mm: convert page cpupid functions to folios' - Some kmemleak fixups in Liu Shixin's series 'Some bugfix about kmemleak' - Qi Zheng has improved our handling of memoryless nodes by keeping them off the allocation fallback list. This is done in the series 'handle memoryless nodes more appropriately' - khugepaged conversions from Vishal Moola in the series 'Some khugepaged folio conversions'" [ bcachefs conflicts with the dynamically allocated shrinkers have been resolved as per Stephen Rothwell in https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/ with help from Qi Zheng. The clone3 test filtering conflict was half-arsed by yours truly ] * tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits) mm/damon/sysfs: update monitoring target regions for online input commit mm/damon/sysfs: remove requested targets when online-commit inputs selftests: add a sanity check for zswap Documentation: maple_tree: fix word spelling error mm/vmalloc: fix the unchecked dereference warning in vread_iter() zswap: export compression failure stats Documentation: ubsan: drop "the" from article title mempolicy: migration attempt to match interleave nodes mempolicy: mmap_lock is not needed while migrating folios mempolicy: alloc_pages_mpol() for NUMA policy without vma mm: add page_rmappable_folio() wrapper mempolicy: remove confusing MPOL_MF_LAZY dead code mempolicy: mpol_shared_policy_init() without pseudo-vma mempolicy trivia: use pgoff_t in shared mempolicy tree mempolicy trivia: slightly more consistent naming mempolicy trivia: delete those ancient pr_debug()s mempolicy: fix migrate_pages(2) syscall return nr_failed kernfs: drop shared NUMA mempolicy hooks hugetlbfs: drop shared NUMA mempolicy pretence mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets() ...
2023-10-30Merge tag 'sched-core-2023-10-28' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: "Fair scheduler (SCHED_OTHER) improvements: - Remove the old and now unused SIS_PROP code & option - Scan cluster before LLC in the wake-up path - Use candidate prev/recent_used CPU if scanning failed for cluster wakeup NUMA scheduling improvements: - Improve the VMA access-PID code to better skip/scan VMAs - Extend tracing to cover VMA-skipping decisions - Improve/fix the recently introduced sched_numa_find_nth_cpu() code - Generalize numa_map_to_online_node() Energy scheduling improvements: - Remove the EM_MAX_COMPLEXITY limit - Add tracepoints to track energy computation - Make the behavior of the 'sched_energy_aware' sysctl more consistent - Consolidate and clean up access to a CPU's max compute capacity - Fix uclamp code corner cases RT scheduling improvements: - Drive dl_rq->overloaded with dl_rq->pushable_dl_tasks updates - Drive the ->rto_mask with rt_rq->pushable_tasks updates Scheduler scalability improvements: - Rate-limit updates to tg->load_avg - On x86 disable IBRS when CPU is offline to improve single-threaded performance - Micro-optimize in_task() and in_interrupt() - Micro-optimize the PSI code - Avoid updating PSI triggers and ->rtpoll_total when there are no state changes Core scheduler infrastructure improvements: - Use saved_state to reduce some spurious freezer wakeups - Bring in a handful of fast-headers improvements to scheduler headers - Make the scheduler UAPI headers more widely usable by user-space - Simplify the control flow of scheduler syscalls by using lock guards - Fix sched_setaffinity() vs. CPU hotplug race Scheduler debuggability improvements: - Disallow writing invalid values to sched_rt_period_us - Fix a race in the rq-clock debugging code triggering warnings - Fix a warning in the bandwidth distribution code - Micro-optimize in_atomic_preempt_off() checks - Enforce that the tasklist_lock is held in for_each_thread() - Print the TGID in sched_show_task() - Remove the /proc/sys/kernel/sched_child_runs_first sysctl ... and misc cleanups & fixes" * tag 'sched-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (82 commits) sched/fair: Remove SIS_PROP sched/fair: Use candidate prev/recent_used CPU if scanning failed for cluster wakeup sched/fair: Scan cluster before scanning LLC in wake-up path sched: Add cpus_share_resources API sched/core: Fix RQCF_ACT_SKIP leak sched/fair: Remove unused 'curr' argument from pick_next_entity() sched/nohz: Update comments about NEWILB_KICK sched/fair: Remove duplicate #include sched/psi: Update poll => rtpoll in relevant comments sched: Make PELT acronym definition searchable sched: Fix stop_one_cpu_nowait() vs hotplug sched/psi: Bail out early from irq time accounting sched/topology: Rename 'DIE' domain to 'PKG' sched/psi: Delete the 'update_total' function parameter from update_triggers() sched/psi: Avoid updating PSI triggers and ->rtpoll_total when there are no state changes sched/headers: Remove comment referring to rq::cpu_load, since this has been removed sched/numa: Complete scanning of inactive VMAs when there is no alternative sched/numa: Complete scanning of partial VMAs regardless of PID activity sched/numa: Move up the access pid reset logic sched/numa: Trace decisions related to skipping VMAs ...
2023-10-25mempolicy: migration attempt to match interleave nodesHugh Dickins
Improve alloc_migration_target_by_mpol()'s treatment of MPOL_INTERLEAVE. Make an effort in do_mbind(), to identify the correct interleave index for the first page to be migrated, so that it and all subsequent pages from the same vma will be targeted to precisely their intended nodes. Pages from following vmas will still be interleaved from the requested nodemask, but perhaps starting from a different base. Whether this is worth doing at all, or worth improving further, is arguable: queue_folio_required() is right not to care about the precise placement on interleaved nodes; but this little effort seems appropriate. [hughd@google.com: do vma_iter search under mmap_write_unlock()] Link: https://lkml.kernel.org/r/3311d544-fb05-a7f1-1b74-16aa0f6cd4fe@google.com Link: https://lkml.kernel.org/r/77954a5-9c9b-1c11-7d5c-3262c01b895f@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy: mmap_lock is not needed while migrating foliosHugh Dickins
mbind(2) holds down_write of current task's mmap_lock throughout (exclusive because it needs to set the new mempolicy on the vmas); migrate_pages(2) holds down_read of pid's mmap_lock throughout. They both hold mmap_lock across the internal migrate_pages(), under which all new page allocations (huge or small) are made. I'm nervous about it; and migrate_pages() certainly does not need mmap_lock itself. It's done this way for mbind(2), because its page allocator is vma_alloc_folio() or alloc_hugetlb_folio_vma(), both of which depend on vma and address. Now that we have alloc_pages_mpol(), depending on (refcounted) memory policy and interleave index, mbind(2) can be modified to use that or alloc_hugetlb_folio_nodemask(), and then not need mmap_lock across the internal migrate_pages() at all: add alloc_migration_target_by_mpol() to replace mbind's new_page(). (After that change, alloc_hugetlb_folio_vma() is used by nothing but a userfaultfd function: move it out of hugetlb.h and into the #ifdef.) migrate_pages(2) has chosen its target node before migrating, so can continue to use the standard alloc_migration_target(); but let it take and drop mmap_lock just around migrate_to_node()'s queue_pages_range(): neither the node-to-node calculations nor the page migrations need it. It seems unlikely, but it is conceivable that some userspace depends on the kernel's mmap_lock exclusion here, instead of doing its own locking: more likely in a testsuite than in real life. It is also possible, of course, that some pages on the list will be munmapped by another thread before they are migrated, or a newer memory policy applied to the range by that time: but such races could happen before, as soon as mmap_lock was dropped, so it does not appear to be a concern. Link: https://lkml.kernel.org/r/21e564e8-269f-6a89-7ee2-fd612831c289@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy: alloc_pages_mpol() for NUMA policy without vmaHugh Dickins
Shrink shmem's stack usage by eliminating the pseudo-vma from its folio allocation. alloc_pages_mpol(gfp, order, pol, ilx, nid) becomes the principal actor for passing mempolicy choice down to __alloc_pages(), rather than vma_alloc_folio(gfp, order, vma, addr, hugepage). vma_alloc_folio() and alloc_pages() remain, but as wrappers around alloc_pages_mpol(). alloc_pages_bulk_*() untouched, except to provide the additional args to policy_nodemask(), which subsumes policy_node(). Cleanup throughout, cutting out some unhelpful "helpers". It would all be much simpler without MPOL_INTERLEAVE, but that adds a dynamic to the constant mpol: complicated by v3.6 commit 09c231cb8bfd ("tmpfs: distribute interleave better across nodes"), which added ino bias to the interleave, hidden from mm/mempolicy.c until this commit. Hence "ilx" throughout, the "interleave index". Originally I thought it could be done just with nid, but that's wrong: the nodemask may come from the shared policy layer below a shmem vma, or it may come from the task layer above a shmem vma; and without the final nodemask then nodeid cannot be decided. And how ilx is applied depends also on page order. The interleave index is almost always irrelevant unless MPOL_INTERLEAVE: with one exception in alloc_pages_mpol(), where the NO_INTERLEAVE_INDEX passed down from vma-less alloc_pages() is also used as hint not to use THP-style hugepage allocation - to avoid the overhead of a hugepage arg (though I don't understand why we never just added a GFP bit for THP - if it actually needs a different allocation strategy from other pages of the same order). vma_alloc_folio() still carries its hugepage arg here, but it is not used, and should be removed when agreed. get_vma_policy() no longer allows a NULL vma: over time I believe we've eradicated all the places which used to need it e.g. swapoff and madvise used to pass NULL vma to read_swap_cache_async(), but now know the vma. [hughd@google.com: handle NULL mpol being passed to __read_swap_cache_async()] Link: https://lkml.kernel.org/r/ea419956-4751-0102-21f7-9c93cb957892@google.com Link: https://lkml.kernel.org/r/74e34633-6060-f5e3-aee-7040d43f2e93@google.com Link: https://lkml.kernel.org/r/1738368e-bac0-fd11-ed7f-b87142a939fe@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Huang Ying <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Domenico Cerasuolo <mimmocerasuolo@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mm: add page_rmappable_folio() wrapperHugh Dickins
folio_prep_large_rmappable() is being used repeatedly along with a conversion from page to folio, a check non-NULL, a check order > 1: wrap it all up into struct folio *page_rmappable_folio(struct page *). Link: https://lkml.kernel.org/r/8d92c6cf-eebe-748-e29c-c8ab224c741@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy: remove confusing MPOL_MF_LAZY dead codeHugh Dickins
v3.8 commit b24f53a0bea3 ("mm: mempolicy: Add MPOL_MF_LAZY") introduced MPOL_MF_LAZY, and included it in the MPOL_MF_VALID flags; but a720094ded8 ("mm: mempolicy: Hide MPOL_NOOP and MPOL_MF_LAZY from userspace for now") immediately removed it from MPOL_MF_VALID flags, pending further review. "This will need to be revisited", but it has not been reinstated. The present state is confusing: there is dead code in mm/mempolicy.c to handle MPOL_MF_LAZY cases which can never occur. Remove that: it can be resurrected later if necessary. But keep the definition of MPOL_MF_LAZY, which must remain in the UAPI, even though it always fails with EINVAL. https://lore.kernel.org/linux-mm/1553041659-46787-1-git-send-email-yang.shi@linux.alibaba.com/ links to a previous request to remove MPOL_MF_LAZY. Link: https://lkml.kernel.org/r/80c9665c-1c3f-17ba-21a3-f6115cebf7d@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Yang Shi <shy828301@gmail.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy: mpol_shared_policy_init() without pseudo-vmaHugh Dickins
mpol_shared_policy_init() does not need to use a pseudo-vma: it can use sp_alloc() and sp_insert() directly, since the object's shared policy tree is empty and inaccessible (needing no lock) at get_inode() time. Link: https://lkml.kernel.org/r/3bef62d8-ae78-4c2-533-56a44ae425c@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy trivia: use pgoff_t in shared mempolicy treeHugh Dickins
Prefer the more explicit "pgoff_t" to "unsigned long" when dealing with a shared mempolicy tree. Delete confusing comment about pseudo mm vmas. Link: https://lkml.kernel.org/r/5451157-3818-4af5-fd2c-5d26a5d1dc53@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy trivia: slightly more consistent namingHugh Dickins
Before getting down to work, do a little cleanup, mainly of inconsistent variable naming. I gave up trying to rationalize mpol versus pol versus policy, and node versus nid, but let's avoid p and nd. Remove a few superfluous blank lines, but add one; and here prefer vma->vm_policy to vma_policy(vma) - the latter being appropriate in other sources, which have to allow for !CONFIG_NUMA. That intriguing line about KERNEL_DS? should have gone in v2.6.15, when numa_policy_init() stopped using set_mempolicy(2)'s system call handler. Link: https://lkml.kernel.org/r/68287974-b6ae-7df-4ba-d19ddd69cbf@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy trivia: delete those ancient pr_debug()sHugh Dickins
Delete those ancient pr_debug()s - PDprintk()s in Andi Kleen's original submission of core NUMA API, and useful when debugging shared mempolicy lifetime back then, but not used recently. Link: https://lkml.kernel.org/r/f25135-ffb2-40d8-9577-720772b333@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-25mempolicy: fix migrate_pages(2) syscall return nr_failedHugh Dickins
"man 2 migrate_pages" says "On success migrate_pages() returns the number of pages that could not be moved". Although 5.3 and 5.4 commits fixed mbind(MPOL_MF_STRICT|MPOL_MF_MOVE*) to fail with EIO when not all pages could be moved (because some could not be isolated for migration), migrate_pages(2) was left still reporting only those pages failing at the migration stage, forgetting those failing at the earlier isolation stage. Fix that by accumulating a long nr_failed count in struct queue_pages, returned by queue_pages_range() when it's not returning an error, for adding on to the nr_failed count from migrate_pages() in mm/migrate.c. A count of pages? It's more a count of folios, but changing it to pages would entail more work (also in mm/migrate.c): does not seem justified. queue_pages_range() itself should only return -EIO in the "strictly unmovable" case (STRICT without any MOVEs): in that case it's best to break out as soon as nr_failed gets set; but otherwise it should continue to isolate pages for MOVing even when nr_failed - as the mbind(2) manpage promises. There's a case when nr_failed should be incremented when it was missed: queue_folios_pte_range() and queue_folios_hugetlb() count the transient migration entries, like queue_folios_pmd() already did. And there's a case when nr_failed should not be incremented when it would have been: in meeting later PTEs of the same large folio, which can only be isolated once: fixed by recording the current large folio in struct queue_pages. Clean up the affected functions, fixing or updating many comments. Bool migrate_folio_add(), without -EIO: true if adding, or if skipping shared (but its arguable folio_estimated_sharers() heuristic left unchanged). Use MPOL_MF_WRLOCK flag to queue_pages_range(), instead of bool lock_vma. Use explicit STRICT|MOVE* flags where queue_pages_test_walk() checks for skipping, instead of hiding them behind MPOL_MF_VALID. Link: https://lkml.kernel.org/r/9a6b0b9-3bb-dbef-8adf-efab4397b8d@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Christoph Lameter <cl@linux.com> Cc: David Hildenbrand <david@redhat.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Michal Hocko <mhocko@suse.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Tejun heo <tj@kernel.org> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18mm: abstract the vma_merge()/split_vma() pattern for mprotect() et al.Lorenzo Stoakes
mprotect() and other functions which change VMA parameters over a range each employ a pattern of:- 1. Attempt to merge the range with adjacent VMAs. 2. If this fails, and the range spans a subset of the VMA, split it accordingly. This is open-coded and duplicated in each case. Also in each case most of the parameters passed to vma_merge() remain the same. Create a new function, vma_modify(), which abstracts this operation, accepting only those parameters which can be changed. To avoid the mess of invoking each function call with unnecessary parameters, create inline wrapper functions for each of the modify operations, parameterised only by what is required to perform the action. We can also significantly simplify the logic - by returning the VMA if we split (or merged VMA if we do not) we no longer need specific handling for merge/split cases in any of the call sites. Note that the userfaultfd_release() case works even though it does not split VMAs - since start is set to vma->vm_start and end is set to vma->vm_end, the split logic does not trigger. In addition, since we calculate pgoff to be equal to vma->vm_pgoff + (start - vma->vm_start) >> PAGE_SHIFT, and start - vma->vm_start will be 0 in this instance, this invocation will remain unchanged. We eliminate a VM_WARN_ON() in mprotect_fixup() as this simply asserts that vma_merge() correctly ensures that flags remain the same, something that is already checked in is_mergeable_vma() and elsewhere, and in any case is not specific to mprotect(). Link: https://lkml.kernel.org/r/0dfa9368f37199a423674bf0ee312e8ea0619044.1697043508.git.lstoakes@gmail.com Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Christian Brauner <brauner@kernel.org> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-18Merge mm-hotfixes-stable into mm-stable to pick up depended-upon changes.Andrew Morton
2023-10-16sched/numa, mm: make numa migrate functions to take a folioKefeng Wang
The cpupid (or access time) is stored in the head page for THP, so it is safely to make should_numa_migrate_memory() and numa_hint_fault_latency() to take a folio. This is in preparation for large folio numa balancing. Link: https://lkml.kernel.org/r/20230921074417.24004-7-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-16mm: mempolicy: make mpol_misplaced() to take a folioKefeng Wang
In preparation for large folio numa balancing, make mpol_misplaced() to take a folio, no functional change intended. Link: https://lkml.kernel.org/r/20230921074417.24004-6-wangkefeng.wang@huawei.com Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Hugh Dickins <hughd@google.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-10-07Merge branch 'sched/urgent' into sched/core, to pick up fixes and refresh ↵Ingo Molnar
the branch Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-10-06mm/mempolicy: fix set_mempolicy_home_node() previous VMA pointerLiam R. Howlett
The two users of mbind_range() are expecting that mbind_range() will update the pointer to the previous VMA, or return an error. However, set_mempolicy_home_node() does not call mbind_range() if there is no VMA policy. The fix is to update the pointer to the previous VMA prior to continuing iterating the VMAs when there is no policy. Users may experience a WARN_ON() during VMA policy updates when updating a range of VMAs on the home node. Link: https://lkml.kernel.org/r/20230928172432.2246534-1-Liam.Howlett@oracle.com Link: https://lore.kernel.org/linux-mm/CALcu4rbT+fMVNaO_F2izaCT+e7jzcAciFkOvk21HGJsmLcUuwQ@mail.gmail.com/ Fixes: f4e9e0e69468 ("mm/mempolicy: fix use-after-free of VMA iterator") Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reported-by: Yikebaer Aizezi <yikebaer61@gmail.com> Closes: https://lore.kernel.org/linux-mm/CALcu4rbT+fMVNaO_F2izaCT+e7jzcAciFkOvk21HGJsmLcUuwQ@mail.gmail.com/ Reviewed-by: Lorenzo Stoakes <lstoakes@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-29mm: mempolicy: keep VMA walk if both MPOL_MF_STRICT and MPOL_MF_MOVE are ↵Yang Shi
specified When calling mbind() with MPOL_MF_{MOVE|MOVEALL} | MPOL_MF_STRICT, kernel should attempt to migrate all existing pages, and return -EIO if there is misplaced or unmovable page. Then commit 6f4576e3687b ("mempolicy: apply page table walker on queue_pages_range()") messed up the return value and didn't break VMA scan early ianymore when MPOL_MF_STRICT alone. The return value problem was fixed by commit a7f40cfe3b7a ("mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified"), but it broke the VMA walk early if unmovable page is met, it may cause some pages are not migrated as expected. The code should conceptually do: if (MPOL_MF_MOVE|MOVEALL) scan all vmas try to migrate the existing pages return success else if (MPOL_MF_MOVE* | MPOL_MF_STRICT) scan all vmas try to migrate the existing pages return -EIO if unmovable or migration failed else /* MPOL_MF_STRICT alone */ break early if meets unmovable and don't call mbind_range() at all else /* none of those flags */ check the ranges in test_walk, EFAULT without mbind_range() if discontig. Fixed the behavior. Link: https://lkml.kernel.org/r/20230920223242.3425775-1-yang@os.amperecomputing.com Fixes: a7f40cfe3b7a ("mm: mempolicy: make mbind() return -EIO when MPOL_MF_STRICT is specified") Signed-off-by: Yang Shi <yang@os.amperecomputing.com> Cc: Hugh Dickins <hughd@google.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Oscar Salvador <osalvador@suse.de> Cc: Rafael Aquini <aquini@redhat.com> Cc: Kirill A. Shutemov <kirill@shutemov.name> Cc: David Rientjes <rientjes@google.com> Cc: <stable@vger.kernel.org> [4.9+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-15numa: Generalize numa_map_to_online_node()Yury Norov
The function in fact searches the nearest node for a given one, based on a N_ONLINE state. This is a common pattern to search for a nearest node. This patch converts numa_map_to_online_node() to numa_nearest_node() so that others won't need to opencode the logic. Signed-off-by: Yury Norov <yury.norov@gmail.com> Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Mel Gorman <mgorman@suse.de> Link: https://lore.kernel.org/r/20230819141239.287290-2-yury.norov@gmail.com
2023-08-21mm: convert prep_transhuge_page() to folio_prep_large_rmappable()Matthew Wilcox (Oracle)
Match folio_undo_large_rmappable(), and move the casting from page to folio into the callers (which they were largely doing anyway). Link: https://lkml.kernel.org/r/20230816151201.3655946-6-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Yanteng Si <siyanteng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-08-21mm: enable page walking API to lock vmas during the walkSuren Baghdasaryan
walk_page_range() and friends often operate under write-locked mmap_lock. With introduction of vma locks, the vmas have to be locked as well during such walks to prevent concurrent page faults in these areas. Add an additional member to mm_walk_ops to indicate locking requirements for the walk. The change ensures that page walks which prevent concurrent page faults by write-locking mmap_lock, operate correctly after introduction of per-vma locks. With per-vma locks page faults can be handled under vma lock without taking mmap_lock at all, so write locking mmap_lock would not stop them. The change ensures vmas are properly locked during such walks. A sample issue this solves is do_mbind() performing queue_pages_range() to queue pages for migration. Without this change a concurrent page can be faulted into the area and be left out of migration. Link: https://lkml.kernel.org/r/20230804152724.3090321-2-surenb@google.com Signed-off-by: Suren Baghdasaryan <surenb@google.com> Suggested-by: Linus Torvalds <torvalds@linuxfoundation.org> Suggested-by: Jann Horn <jannh@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Hugh Dickins <hughd@google.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Laurent Dufour <ldufour@linux.ibm.com> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Michel Lespinasse <michel@lespinasse.org> Cc: Peter Xu <peterx@redhat.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-07-28mm/mempolicy: Take VMA lock before replacing policyJann Horn
mbind() calls down into vma_replace_policy() without taking the per-VMA locks, replaces the VMA's vma->vm_policy pointer, and frees the old policy. That's bad; a concurrent page fault might still be using the old policy (in vma_alloc_folio()), resulting in use-after-free. Normally this will manifest as a use-after-free read first, but it can result in memory corruption, including because vma_alloc_folio() can call mpol_cond_put() on the freed policy, which conditionally changes the policy's refcount member. This bug is specific to CONFIG_NUMA, but it does also affect non-NUMA systems as long as the kernel was built with CONFIG_NUMA. Signed-off-by: Jann Horn <jannh@google.com> Reviewed-by: Suren Baghdasaryan <surenb@google.com> Fixes: 5e31275cc997 ("mm: add per-VMA lock and helper functions to control it") Cc: stable@kernel.org Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-06-19mm: ptep_get() conversionRyan Roberts
Convert all instances of direct pte_t* dereferencing to instead use ptep_get() helper. This means that by default, the accesses change from a C dereference to a READ_ONCE(). This is technically the correct thing to do since where pgtables are modified by HW (for access/dirty) they are volatile and therefore we should always ensure READ_ONCE() semantics. But more importantly, by always using the helper, it can be overridden by the architecture to fully encapsulate the contents of the pte. Arch code is deliberately not converted, as the arch code knows best. It is intended that arch code (arm64) will override the default with its own implementation that can (e.g.) hide certain bits from the core code, or determine young/dirty status by mixing in state from another source. Conversion was done using Coccinelle: ---- // $ make coccicheck \ // COCCI=ptepget.cocci \ // SPFLAGS="--include-headers" \ // MODE=patch virtual patch @ depends on patch @ pte_t *v; @@ - *v + ptep_get(v) ---- Then reviewed and hand-edited to avoid multiple unnecessary calls to ptep_get(), instead opting to store the result of a single call in a variable, where it is correct to do so. This aims to negate any cost of READ_ONCE() and will benefit arch-overrides that may be more complex. Included is a fix for an issue in an earlier version of this patch that was pointed out by kernel test robot. The issue arose because config MMU=n elides definition of the ptep helper functions, including ptep_get(). HUGETLB_PAGE=n configs still define a simple huge_ptep_clear_flush() for linking purposes, which dereferences the ptep. So when both configs are disabled, this caused a build error because ptep_get() is not defined. Fix by continuing to do a direct dereference when MMU=n. This is safe because for this config the arch code cannot be trying to virtualize the ptes because none of the ptep helpers are defined. Link: https://lkml.kernel.org/r/20230612151545.3317766-4-ryan.roberts@arm.com Reported-by: kernel test robot <lkp@intel.com> Link: https://lore.kernel.org/oe-kbuild-all/202305120142.yXsNEo6H-lkp@intel.com/ Signed-off-by: Ryan Roberts <ryan.roberts@arm.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Potapenko <glider@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Christian Brauner <brauner@kernel.org> Cc: Christoph Hellwig <hch@infradead.org> Cc: Daniel Vetter <daniel@ffwll.ch> Cc: Dave Airlie <airlied@gmail.com> Cc: Dimitri Sivanich <dimitri.sivanich@hpe.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Jérôme Glisse <jglisse@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Oleksandr Tyshchenko <oleksandr_tyshchenko@epam.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: SeongJae Park <sj@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Uladzislau Rezki (Sony) <urezki@gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-19mm/pagewalkers: ACTION_AGAIN if pte_offset_map_lock() failsHugh Dickins
Simple walk_page_range() users should set ACTION_AGAIN to retry when pte_offset_map_lock() fails. No need to check pmd_trans_unstable(): that was precisely to avoid the possiblity of calling pte_offset_map() on a racily removed or inserted THP entry, but such cases are now safely handled inside it. Likewise there is no need to check pmd_none() or pmd_bad() before calling it. Link: https://lkml.kernel.org/r/c77d9d10-3aad-e3ce-4896-99e91c7947f3@google.com Signed-off-by: Hugh Dickins <hughd@google.com> Reviewed-by: SeongJae Park <sj@kernel.org> for mm/damon part Cc: Alistair Popple <apopple@nvidia.com> Cc: Anshuman Khandual <anshuman.khandual@arm.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: Christophe Leroy <christophe.leroy@csgroup.eu> Cc: Christoph Hellwig <hch@infradead.org> Cc: David Hildenbrand <david@redhat.com> Cc: "Huang, Ying" <ying.huang@intel.com> Cc: Ira Weiny <ira.weiny@intel.com> Cc: Jason Gunthorpe <jgg@ziepe.ca> Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Mike Rapoport (IBM) <rppt@kernel.org> Cc: Minchan Kim <minchan@kernel.org> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Pavel Tatashin <pasha.tatashin@soleen.com> Cc: Peter Xu <peterx@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Qi Zheng <zhengqi.arch@bytedance.com> Cc: Ralph Campbell <rcampbell@nvidia.com> Cc: Ryan Roberts <ryan.roberts@arm.com> Cc: Song Liu <song@kernel.org> Cc: Steven Price <steven.price@arm.com> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com> Cc: Will Deacon <will@kernel.org> Cc: Yang Shi <shy828301@gmail.com> Cc: Yu Zhao <yuzhao@google.com> Cc: Zack Rusin <zackr@vmware.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-06-09mm: convert migrate_pages() to work on foliosMatthew Wilcox (Oracle)
Almost all of the callers & implementors of migrate_pages() were already converted to use folios. compaction_alloc() & compaction_free() are trivial to convert a part of this patch and not worth splitting out. Link: https://lkml.kernel.org/r/20230513001101.276972-1-willy@infradead.org Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-05-02mm/mempolicy: correctly update prev when policy is equal on mbindLorenzo Stoakes
The refactoring in commit f4e9e0e69468 ("mm/mempolicy: fix use-after-free of VMA iterator") introduces a subtle bug which arises when attempting to apply a new NUMA policy across a range of VMAs in mbind_range(). The refactoring passes a **prev pointer to keep track of the previous VMA in order to reduce duplication, and in all but one case it keeps this correctly updated. The bug arises when a VMA within the specified range has an equivalent policy as determined by mpol_equal() - which unlike other cases, does not update prev. This can result in a situation where, later in the iteration, a VMA is found whose policy does need to change. At this point, vma_merge() is invoked with prev pointing to a VMA which is before the previous VMA. Since vma_merge() discovers the curr VMA by looking for the one immediately after prev, it will now be in a situation where this VMA is incorrect and the merge will not proceed correctly. This is checked in the VM_WARN_ON() invariant case with end > curr->vm_end, which, if a merge is possible, results in a warning (if CONFIG_DEBUG_VM is specified). I note that vma_merge() performs these invariant checks only after merge_prev/merge_next are checked, which is debatable as it hides this issue if no merge is possible even though a buggy situation has arisen. The solution is simply to update the prev pointer even when policies are equal. This caused a bug to arise in the 6.2.y stable tree, and this patch resolves this bug. Link: https://lkml.kernel.org/r/83f1d612acb519d777bebf7f3359317c4e7f4265.1682866629.git.lstoakes@gmail.com Fixes: f4e9e0e69468 ("mm/mempolicy: fix use-after-free of VMA iterator") Signed-off-by: Lorenzo Stoakes <lstoakes@gmail.com> Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/oe-lkp/202304292203.44ddeff6-oliver.sang@intel.com Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Mel Gorman <mgorman@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-16mm/mempolicy: fix use-after-free of VMA iteratorLiam R. Howlett
set_mempolicy_home_node() iterates over a list of VMAs and calls mbind_range() on each VMA, which also iterates over the singular list of the VMA passed in and potentially splits the VMA. Since the VMA iterator is not passed through, set_mempolicy_home_node() may now point to a stale node in the VMA tree. This can result in a UAF as reported by syzbot. Avoid the stale maple tree node by passing the VMA iterator through to the underlying call to split_vma(). mbind_range() is also overly complicated, since there are two calling functions and one already handles iterating over the VMAs. Simplify mbind_range() to only handle merging and splitting of the VMAs. Align the new loop in do_mbind() and existing loop in set_mempolicy_home_node() to use the reduced mbind_range() function. This allows for a single location of the range calculation and avoids constantly looking up the previous VMA (since this is a loop over the VMAs). Link: https://lore.kernel.org/linux-mm/000000000000c93feb05f87e24ad@google.com/ Fixes: 66850be55e8e ("mm/mempolicy: use vma iterator & maple state instead of vma linked list") Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reported-by: syzbot+a7c1ec5b1d71ceaa5186@syzkaller.appspotmail.com Link: https://lkml.kernel.org/r/20230410152205.2294819-1-Liam.Howlett@oracle.com Tested-by: syzbot+a7c1ec5b1d71ceaa5186@syzkaller.appspotmail.com Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-20mm: hugetlb: change to return bool for isolate_hugetlb()Baolin Wang
Now the isolate_hugetlb() only returns 0 or -EBUSY, and most users did not care about the negative value, thus we can convert the isolate_hugetlb() to return a boolean value to make code more clear when checking the hugetlb isolation state. Moreover converts 2 users which will consider the negative value returned by isolate_hugetlb(). No functional changes intended. [akpm@linux-foundation.org: shorten locked section, per SeongJae Park] Link: https://lkml.kernel.org/r/12a287c5bebc13df304387087bbecc6421510849.1676424378.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Reviewed-by: SeongJae Park <sj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-20mm: change to return bool for folio_isolate_lru()Baolin Wang
Patch series "Change the return value for page isolation functions", v3. Now the page isolation functions did not return a boolean to indicate success or not, instead it will return a negative error when failed to isolate a page. So below code used in most places seem a boolean success/failure thing, which can confuse people whether the isolation is successful. if (folio_isolate_lru(folio)) continue; Moreover the page isolation functions only return 0 or -EBUSY, and most users did not care about the negative error except for few users, thus we can convert all page isolation functions to return a boolean value, which can remove the confusion to make code more clear. No functional changes intended in this patch series. This patch (of 4): Now the folio_isolate_lru() did not return a boolean value to indicate isolation success or not, however below code checking the return value can make people think that it was a boolean success/failure thing, which makes people easy to make mistakes (see the fix patch[1]). if (folio_isolate_lru(folio)) continue; Thus it's better to check the negative error value expilictly returned by folio_isolate_lru(), which makes code more clear per Linus's suggestion[2]. Moreover Matthew suggested we can convert the isolation functions to return a boolean[3], since most users did not care about the negative error value, and can also remove the confusing of checking return value. So this patch converts the folio_isolate_lru() to return a boolean value, which means return 'true' to indicate the folio isolation is successful, and 'false' means a failure to isolation. Meanwhile changing all users' logic of checking the isolation state. No functional changes intended. [1] https://lore.kernel.org/all/20230131063206.28820-1-Kuan-Ying.Lee@mediatek.com/T/#u [2] https://lore.kernel.org/all/CAHk-=wiBrY+O-4=2mrbVyxR+hOqfdJ=Do6xoucfJ9_5az01L4Q@mail.gmail.com/ [3] https://lore.kernel.org/all/Y+sTFqwMNAjDvxw3@casper.infradead.org/ Link: https://lkml.kernel.org/r/cover.1676424378.git.baolin.wang@linux.alibaba.com Link: https://lkml.kernel.org/r/8a4e3679ed4196168efadf7ea36c038f2f7d5aa9.1676424378.git.baolin.wang@linux.alibaba.com Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com> Reviewed-by: SeongJae Park <sj@kernel.org> Acked-by: David Hildenbrand <david@redhat.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Miaohe Lin <linmiaohe@huawei.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Naoya Horiguchi <naoya.horiguchi@nec.com> Cc: Oscar Salvador <osalvador@suse.de> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeelb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/mempolicy: convert migrate_page_add() to migrate_folio_add()Vishal Moola (Oracle)
Replace migrate_page_add() with migrate_folio_add(). migrate_folio_add() does the same a migrate_page_add() but takes in a folio instead of a page. This removes a couple of calls to compound_head(). Link: https://lkml.kernel.org/r/20230130201833.27042-7-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Reviewed-by: Yin Fengwei <fengwei.yin@intel.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/mempolicy: convert queue_pages_required() to queue_folio_required()Vishal Moola (Oracle)
Replace queue_pages_required() with queue_folio_required(). queue_folio_required() does the same as queue_pages_required(), except takes in a folio instead of a page. Link: https://lkml.kernel.org/r/20230130201833.27042-6-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: "Yin, Fengwei" <fengwei.yin@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/mempolicy: convert queue_pages_hugetlb() to queue_folios_hugetlb()Vishal Moola (Oracle)
This change is in preparation for the conversion of queue_pages_required() to queue_folio_required() and migrate_page_add() to migrate_folio_add(). Link: https://lkml.kernel.org/r/20230130201833.27042-5-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: "Yin, Fengwei" <fengwei.yin@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/mempolicy: convert queue_pages_pte_range() to queue_folios_pte_range()Vishal Moola (Oracle)
This function now operates on folios associated with ptes instead of pages. This change is in preparation for the conversion of queue_pages_required() to queue_folio_required() and migrate_page_add() to migrate_folio_add(). Link: https://lkml.kernel.org/r/20230130201833.27042-4-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: "Yin, Fengwei" <fengwei.yin@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/mempolicy: convert queue_pages_pmd() to queue_folios_pmd()Vishal Moola (Oracle)
The function now operates on a folio instead of the page associated with a pmd. This change is in preparation for the conversion of queue_pages_required() to queue_folio_required() and migrate_page_add() to migrate_folio_add(). Link: https://lkml.kernel.org/r/20230130201833.27042-3-vishal.moola@gmail.com Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: Jane Chu <jane.chu@oracle.com> Cc: "Yin, Fengwei" <fengwei.yin@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert hugetlb fault paths to use alloc_hugetlb_folio()Sidhartha Kumar
Change alloc_huge_page() to alloc_hugetlb_folio() by changing all callers to handle the now folio return type of the function. In this conversion, alloc_huge_page_vma() is also changed to alloc_hugetlb_folio_vma() and hugepage_add_new_anon_rmap() is changed to take in a folio directly. Many additions of '&folio->page' are cleaned up in subsequent patches. hugetlbfs_fallocate() is also refactored to use the RCU + page_cache_next_miss() API. Link: https://lkml.kernel.org/r/20230125170537.96973-5-sidhartha.kumar@oracle.com Suggested-by: Mike Kravetz <mike.kravetz@oracle.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-13mm/hugetlb: convert isolate_hugetlb to foliosSidhartha Kumar
Patch series "continue hugetlb folio conversion", v3. This series continues the conversion of core hugetlb functions to use folios. This series converts many helper funtions in the hugetlb fault path. This is in preparation for another series to convert the hugetlb fault code paths to operate on folios. This patch (of 8): Convert isolate_hugetlb() to take in a folio and convert its callers to pass a folio. Use page_folio() to convert the callers to use a folio is safe as isolate_hugetlb() operates on a head page. Link: https://lkml.kernel.org/r/20230113223057.173292-1-sidhartha.kumar@oracle.com Link: https://lkml.kernel.org/r/20230113223057.173292-2-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com> Cc: John Hubbard <jhubbard@nvidia.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mm: switch vma_merge(), split_vma(), and __split_vma to vma iteratorLiam R. Howlett
Drop the vmi_* functions and transition all users to use the vma iterator directly. Link: https://lkml.kernel.org/r/20230120162650.984577-30-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-09mempolicy: convert to vma iteratorLiam R. Howlett
Use the vma iterator so that the iterator can be invalidated or updated to avoid each caller doing so. Link: https://lkml.kernel.org/r/20230120162650.984577-21-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-31Sync mm-stable with mm-hotfixes-stable to pick up dependent patchesAndrew Morton
Merge branch 'mm-hotfixes-stable' into mm-stable
2023-01-31migrate: hugetlb: check for hugetlb shared PMD in node migrationMike Kravetz
migrate_pages/mempolicy semantics state that CAP_SYS_NICE is required to move pages shared with another process to a different node. page_mapcount > 1 is being used to determine if a hugetlb page is shared. However, a hugetlb page will have a mapcount of 1 if mapped by multiple processes via a shared PMD. As a result, hugetlb pages shared by multiple processes and mapped with a shared PMD can be moved by a process without CAP_SYS_NICE. To fix, check for a shared PMD if mapcount is 1. If a shared PMD is found consider the page shared. Link: https://lkml.kernel.org/r/20230126222721.222195-3-mike.kravetz@oracle.com Fixes: e2d8cf405525 ("migrate: add hugepage migration code to migrate_pages()") Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: Peter Xu <peterx@redhat.com> Acked-by: David Hildenbrand <david@redhat.com> Cc: James Houghton <jthoughton@google.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michal Hocko <mhocko@suse.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev> Cc: Vishal Moola (Oracle) <vishal.moola@gmail.com> Cc: Yang Shi <shy828301@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/uffd: detect pgtable allocation failuresPeter Xu
Before this patch, when there's any pgtable allocation issues happened during change_protection(), the error will be ignored from the syscall. For shmem, there will be an error dumped into the host dmesg. Two issues with that: (1) Doing a trace dump when allocation fails is not anything close to grace. (2) The user should be notified with any kind of such error, so the user can trap it and decide what to do next, either by retrying, or stop the process properly, or anything else. For userfault users, this will change the API of UFFDIO_WRITEPROTECT when pgtable allocation failure happened. It should not normally break anyone, though. If it breaks, then in good ways. One man-page update will be on the way to introduce the new -ENOMEM for UFFDIO_WRITEPROTECT. Not marking stable so we keep the old behavior on the 5.19-till-now kernels. [akpm@linux-foundation.org: coding-style cleanups] Link: https://lkml.kernel.org/r/20230104225207.1066932-4-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Reported-by: James Houghton <jthoughton@google.com> Acked-by: James Houghton <jthoughton@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/mprotect: use long for page accountings and retvalPeter Xu
Switch to use type "long" for page accountings and retval across the whole procedure of change_protection(). The change should have shrinked the possible maximum page number to be half comparing to previous (ULONG_MAX / 2), but it shouldn't overflow on any system either because the maximum possible pages touched by change protection should be ULONG_MAX / PAGE_SIZE. Two reasons to switch from "unsigned long" to "long": 1. It suites better on count_vm_numa_events(), whose 2nd parameter takes a long type. 2. It paves way for returning negative (error) values in the future. Currently the only caller that consumes this retval is change_prot_numa(), where the unsigned long was converted to an int. Since at it, touching up the numa code to also take a long, so it'll avoid any possible overflow too during the int-size convertion. Link: https://lkml.kernel.org/r/20230104225207.1066932-3-peterx@redhat.com Signed-off-by: Peter Xu <peterx@redhat.com> Acked-by: Mike Kravetz <mike.kravetz@oracle.com> Acked-by: James Houghton <jthoughton@google.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Axel Rasmussen <axelrasmussen@google.com> Cc: David Hildenbrand <david@redhat.com> Cc: Muchun Song <songmuchun@bytedance.com> Cc: Nadav Amit <nadav.amit@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/mprotect: drop pgprot_t parameter from change_protection()David Hildenbrand
Being able to provide a custom protection opens the door for inconsistencies and BUGs: for example, accidentally allowing for more permissions than desired by other mechanisms (e.g., softdirty tracking). vma->vm_page_prot should be the single source of truth. Only PROT_NUMA is special: there is no way we can erroneously allow for more permissions when removing all permissions. Special-case using the MM_CP_PROT_NUMA flag. [david@redhat.com: PAGE_NONE might not be defined without CONFIG_NUMA_BALANCING] Link: https://lkml.kernel.org/r/5084ff1c-ebb3-f918-6a60-bacabf550a88@redhat.com Link: https://lkml.kernel.org/r/20221223155616.297723-3-david@redhat.com Signed-off-by: David Hildenbrand <david@redhat.com> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Hugh Dickins <hughd@google.com> Cc: Nadav Amit <nadav.amit@gmail.com> Cc: Peter Xu <peterx@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-01-18mm/mempolicy: do not duplicate policy if it is not applicable for ↵Michal Hocko
set_mempolicy_home_node set_mempolicy_home_node tries to duplicate a memory policy before checking it whether it is applicable for the operation. There is no real reason for doing that and it might actually be a pointless memory allocation and deallocation exercise for MPOL_INTERLEAVE. Not a big problem but we can do better. Simply check the policy before acting on it. Link: https://lkml.kernel.org/r/20221216194537.238047-2-mathieu.desnoyers@efficios.com Signed-off-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Huang Ying <ying.huang@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-12-21mm/mempolicy: fix memory leak in set_mempolicy_home_node system callMathieu Desnoyers
When encountering any vma in the range with policy other than MPOL_BIND or MPOL_PREFERRED_MANY, an error is returned without issuing a mpol_put on the policy just allocated with mpol_dup(). This allows arbitrary users to leak kernel memory. Link: https://lkml.kernel.org/r/20221215194621.202816-1-mathieu.desnoyers@efficios.com Fixes: c6018b4b2549 ("mm/mempolicy: add set_mempolicy_home_node syscall") Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Reviewed-by: Randy Dunlap <rdunlap@infradead.org> Reviewed-by: "Huang, Ying" <ying.huang@intel.com> Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Feng Tang <feng.tang@intel.com> Cc: Michal Hocko <mhocko@kernel.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Mel Gorman <mgorman@techsingularity.net> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Huang Ying <ying.huang@intel.com> Cc: <stable@vger.kernel.org> [5.17+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-20mm/mempolicy: fix mbind_range() arguments to vma_merge()Liam Howlett
Fuzzing produced an invalid argument to vma_merge() which was caught by the newly added verification of the number of VMAs being removed on process exit. Analyzing the failure eventually resulted in finding an issue with the search of a VMA that started at address 0, which caused an underflow and thus the loss of many VMAs being tracked in the tree. Fix the underflow by changing the search of the maple tree to use the start address directly. Link: https://lkml.kernel.org/r/20221015021135.2816178-1-Liam.Howlett@oracle.com Fixes: 66850be55e8e ("mm/mempolicy: use vma iterator & maple state instead of vma linked list") Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com> Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/r/202210052318.5ad10912-oliver.sang@intel.com Cc: Yu Zhao <yuzhao@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03mm/mempolicy: use PAGE_ALIGN instead of open-coding itze zuo
Replace the simple calculation with PAGE_ALIGN. Link: https://lkml.kernel.org/r/20220913015505.1998958-1-zuoze1@huawei.com Signed-off-by: ze zuo <zuoze1@huawei.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-26mm/mempolicy: use vma iterator & maple state instead of vma linked listLiam R. Howlett
Reworked the way mbind_range() finds the first VMA to reuse the maple state and limit the number of tree walks needed. Note, this drops the VM_BUG_ON(!vma) call, which would catch a start address higher than the last VMA. The code was written in a way that allowed no VMA updates to occur and still return success. There should be no functional change to this scenario with the new code. Link: https://lkml.kernel.org/r/20220906194824.2110408-57-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com> Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org> Tested-by: Yu Zhao <yuzhao@google.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: David Hildenbrand <david@redhat.com> Cc: David Howells <dhowells@redhat.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: SeongJae Park <sj@kernel.org> Cc: Sven Schnelle <svens@linux.ibm.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Will Deacon <will@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-09-11mm/hugetlb: add dedicated func to get 'allowed' nodemask for current processFeng Tang
Muchun Song found that after MPOL_PREFERRED_MANY policy was introduced in commit b27abaccf8e8 ("mm/mempolicy: add MPOL_PREFERRED_MANY for multiple preferred nodes"), the policy_nodemask_current()'s semantics for this new policy has been changed, which returns 'preferred' nodes instead of 'allowed' nodes. With the changed semantic of policy_nodemask_current, a task with MPOL_PREFERRED_MANY policy could fail to get its reservation even though it can fall back to other nodes (either defined by cpusets or all online nodes) for that reservation failing mmap calles unnecessarily early. The fix is to not consider MPOL_PREFERRED_MANY for reservations at all because they, unlike MPOL_MBIND, do not pose any actual hard constrain. Michal suggested the policy_nodemask_current() is only used by hugetlb, and could be moved to hugetlb code with more explicit name to enforce the 'allowed' semantics for which only MPOL_BIND policy matters. apply_policy_zone() is made extern to be called in hugetlb code and its return value is changed to bool. [1]. https://lore.kernel.org/lkml/20220801084207.39086-1-songmuchun@bytedance.com/t/ Link: https://lkml.kernel.org/r/20220805005903.95563-1-feng.tang@intel.com Fixes: b27abaccf8e8 ("mm/mempolicy: add MPOL_PREFERRED_MANY for multiple preferred nodes") Signed-off-by: Feng Tang <feng.tang@intel.com> Reported-by: Muchun Song <songmuchun@bytedance.com> Suggested-by: Michal Hocko <mhocko@suse.com> Acked-by: Michal Hocko <mhocko@suse.com> Reviewed-by: Muchun Song <songmuchun@bytedance.com> Cc: Mike Kravetz <mike.kravetz@oracle.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Ben Widawsky <bwidawsk@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>