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* Merge tag 'mm-stable-2023-02-20-13-37' of ↵Linus Torvalds2023-02-231-3/+3
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Daniel Verkamp has contributed a memfd series ("mm/memfd: add F_SEAL_EXEC") which permits the setting of the memfd execute bit at memfd creation time, with the option of sealing the state of the X bit. - Peter Xu adds a patch series ("mm/hugetlb: Make huge_pte_offset() thread-safe for pmd unshare") which addresses a rare race condition related to PMD unsharing. - Several folioification patch serieses from Matthew Wilcox, Vishal Moola, Sidhartha Kumar and Lorenzo Stoakes - Johannes Weiner has a series ("mm: push down lock_page_memcg()") which does perform some memcg maintenance and cleanup work. - SeongJae Park has added DAMOS filtering to DAMON, with the series "mm/damon/core: implement damos filter". These filters provide users with finer-grained control over DAMOS's actions. SeongJae has also done some DAMON cleanup work. - Kairui Song adds a series ("Clean up and fixes for swap"). - Vernon Yang contributed the series "Clean up and refinement for maple tree". - Yu Zhao has contributed the "mm: multi-gen LRU: memcg LRU" series. It adds to MGLRU an LRU of memcgs, to improve the scalability of global reclaim. - David Hildenbrand has added some userfaultfd cleanup work in the series "mm: uffd-wp + change_protection() cleanups". - Christoph Hellwig has removed the generic_writepages() library function in the series "remove generic_writepages". - Baolin Wang has performed some maintenance on the compaction code in his series "Some small improvements for compaction". - Sidhartha Kumar is doing some maintenance work on struct page in his series "Get rid of tail page fields". - David Hildenbrand contributed some cleanup, bugfixing and generalization of pte management and of pte debugging in his series "mm: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE on all architectures with swap PTEs". - Mel Gorman and Neil Brown have removed the __GFP_ATOMIC allocation flag in the series "Discard __GFP_ATOMIC". - Sergey Senozhatsky has improved zsmalloc's memory utilization with his series "zsmalloc: make zspage chain size configurable". - Joey Gouly has added prctl() support for prohibiting the creation of writeable+executable mappings. The previous BPF-based approach had shortcomings. See "mm: In-kernel support for memory-deny-write-execute (MDWE)". - Waiman Long did some kmemleak cleanup and bugfixing in the series "mm/kmemleak: Simplify kmemleak_cond_resched() & fix UAF". - T.J. Alumbaugh has contributed some MGLRU cleanup work in his series "mm: multi-gen LRU: improve". - Jiaqi Yan has provided some enhancements to our memory error statistics reporting, mainly by presenting the statistics on a per-node basis. See the series "Introduce per NUMA node memory error statistics". - Mel Gorman has a second and hopefully final shot at fixing a CPU-hog regression in compaction via his series "Fix excessive CPU usage during compaction". - Christoph Hellwig does some vmalloc maintenance work in the series "cleanup vfree and vunmap". - Christoph Hellwig has removed block_device_operations.rw_page() in ths series "remove ->rw_page". - We get some maple_tree improvements and cleanups in Liam Howlett's series "VMA tree type safety and remove __vma_adjust()". - Suren Baghdasaryan has done some work on the maintainability of our vm_flags handling in the series "introduce vm_flags modifier functions". - Some pagemap cleanup and generalization work in Mike Rapoport's series "mm, arch: add generic implementation of pfn_valid() for FLATMEM" and "fixups for generic implementation of pfn_valid()" - Baoquan He has done some work to make /proc/vmallocinfo and /proc/kcore better represent the real state of things in his series "mm/vmalloc.c: allow vread() to read out vm_map_ram areas". - Jason Gunthorpe rationalized the GUP system's interface to the rest of the kernel in the series "Simplify the external interface for GUP". - SeongJae Park wishes to migrate people from DAMON's debugfs interface over to its sysfs interface. To support this, we'll temporarily be printing warnings when people use the debugfs interface. See the series "mm/damon: deprecate DAMON debugfs interface". - Andrey Konovalov provided the accurately named "lib/stackdepot: fixes and clean-ups" series. - Huang Ying has provided a dramatic reduction in migration's TLB flush IPI rates with the series "migrate_pages(): batch TLB flushing". - Arnd Bergmann has some objtool fixups in "objtool warning fixes". * tag 'mm-stable-2023-02-20-13-37' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (505 commits) include/linux/migrate.h: remove unneeded externs mm/memory_hotplug: cleanup return value handing in do_migrate_range() mm/uffd: fix comment in handling pte markers mm: change to return bool for isolate_movable_page() mm: hugetlb: change to return bool for isolate_hugetlb() mm: change to return bool for isolate_lru_page() mm: change to return bool for folio_isolate_lru() objtool: add UACCESS exceptions for __tsan_volatile_read/write kmsan: disable ftrace in kmsan core code kasan: mark addr_has_metadata __always_inline mm: memcontrol: rename memcg_kmem_enabled() sh: initialize max_mapnr m68k/nommu: add missing definition of ARCH_PFN_OFFSET mm: percpu: fix incorrect size in pcpu_obj_full_size() maple_tree: reduce stack usage with gcc-9 and earlier mm: page_alloc: call panic() when memoryless node allocation fails mm: multi-gen LRU: avoid futile retries migrate_pages: move THP/hugetlb migration support check to simplify code migrate_pages: batch flushing TLB migrate_pages: share more code between _unmap and _move ...
| * lib/stackdepot, mm: rename stack_depot_want_early_initAndrey Konovalov2023-02-161-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rename stack_depot_want_early_init to stack_depot_request_early_init. The old name is confusing, as it hints at returning some kind of intention of stack depot. The new name reflects that this function requests an action from stack depot instead. No functional changes. [akpm@linux-foundation.org: update mm/kmemleak.c] Link: https://lkml.kernel.org/r/359f31bf67429a06e630b4395816a967214ef753.1676063693.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov <andreyknvl@google.com> Reviewed-by: Alexander Potapenko <glider@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * mm: introduce folio_is_pfmemallocSidhartha Kumar2023-01-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | Add a folio equivalent for page_is_pfmemalloc. This removes two instances of page_is_pfmemalloc(folio_page(folio, 0)) so the folio can be used directly. Link: https://lkml.kernel.org/r/20230106215251.599222-1-sidhartha.kumar@oracle.com Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: Sidhartha Kumar <sidhartha.kumar@oracle.com> Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org> Reviewed-by: SeongJae Park <sj@kernel.org> Acked-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | Merge branch 'slab/for-6.3/fixes' into slab/for-linusVlastimil Babka2023-02-211-5/+6
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | Two fixes for SLAB and SLUB - Make it possible to use kmem_cache_alloc_bulk() early in boot when interrupts are not yet enabled, as code doing that start to appear via the maple tree (by Thomas Gleixner). - Fix debugfs-related memory leak (by Greg Kroah-Hartman).
| * | mm, slab/slub: Ensure kmem_cache_alloc_bulk() is available earlyThomas Gleixner2023-02-081-4/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The memory allocators are available during early boot even in the phase where interrupts are disabled and scheduling is not yet possible. The setup is so that GFP_KERNEL allocations work in this phase without causing might_alloc() splats to be emitted because the system state is SYSTEM_BOOTING at that point which prevents the warnings to trigger. Most allocation/free functions use local_irq_save()/restore() or a lock variant of that. But kmem_cache_alloc_bulk() and kmem_cache_free_bulk() use local_[lock]_irq_disable()/enable(), which leads to a lockdep warning when interrupts are enabled during the early boot phase. This went unnoticed so far as there are no early users of these interfaces. The upcoming conversion of the interrupt descriptor store from radix_tree to maple_tree triggered this warning as maple_tree uses the bulk interface. Cure this by moving the kmem_cache_alloc/free() bulk variants of SLUB and SLAB to local[_lock]_irq_save()/restore(). There is obviously no reclaim possible and required at this point so there is no need to expand this coverage further. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
| * | mm/slub: fix memory leak with using debugfs_lookup()Greg Kroah-Hartman2023-02-061-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When calling debugfs_lookup() the result must have dput() called on it, otherwise the memory will leak over time. To make things simpler, just call debugfs_lookup_and_remove() instead which handles all of the logic at once. Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* / mm/sl{a,u}b: fix wrong usages of folio_page() for getting head pagesSeongJae Park2023-01-131-1/+1
|/ | | | | | | | | | | | The standard idiom for getting head page of a given folio is '&folio->page', but some are wrongly using 'folio_page(folio, 0)' for the purpose. Fix those to use the idiom. Suggested-by: Matthew Wilcox <willy@infradead.org> Signed-off-by: SeongJae Park <sj@kernel.org> Reviewed-by: David Hildenbrand <david@redhat.com> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* Merge tag 'mm-stable-2022-12-13' of ↵Linus Torvalds2022-12-131-6/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - More userfaultfs work from Peter Xu - Several convert-to-folios series from Sidhartha Kumar and Huang Ying - Some filemap cleanups from Vishal Moola - David Hildenbrand added the ability to selftest anon memory COW handling - Some cpuset simplifications from Liu Shixin - Addition of vmalloc tracing support by Uladzislau Rezki - Some pagecache folioifications and simplifications from Matthew Wilcox - A pagemap cleanup from Kefeng Wang: we have VM_ACCESS_FLAGS, so use it - Miguel Ojeda contributed some cleanups for our use of the __no_sanitize_thread__ gcc keyword. This series should have been in the non-MM tree, my bad - Naoya Horiguchi improved the interaction between memory poisoning and memory section removal for huge pages - DAMON cleanups and tuneups from SeongJae Park - Tony Luck fixed the handling of COW faults against poisoned pages - Peter Xu utilized the PTE marker code for handling swapin errors - Hugh Dickins reworked compound page mapcount handling, simplifying it and making it more efficient - Removal of the autonuma savedwrite infrastructure from Nadav Amit and David Hildenbrand - zram support for multiple compression streams from Sergey Senozhatsky - David Hildenbrand reworked the GUP code's R/O long-term pinning so that drivers no longer need to use the FOLL_FORCE workaround which didn't work very well anyway - Mel Gorman altered the page allocator so that local IRQs can remnain enabled during per-cpu page allocations - Vishal Moola removed the try_to_release_page() wrapper - Stefan Roesch added some per-BDI sysfs tunables which are used to prevent network block devices from dirtying excessive amounts of pagecache - David Hildenbrand did some cleanup and repair work on KSM COW breaking - Nhat Pham and Johannes Weiner have implemented writeback in zswap's zsmalloc backend - Brian Foster has fixed a longstanding corner-case oddity in file[map]_write_and_wait_range() - sparse-vmemmap changes for MIPS, LoongArch and NIOS2 from Feiyang Chen - Shiyang Ruan has done some work on fsdax, to make its reflink mode work better under xfstests. Better, but still not perfect - Christoph Hellwig has removed the .writepage() method from several filesystems. They only need .writepages() - Yosry Ahmed wrote a series which fixes the memcg reclaim target beancounting - David Hildenbrand has fixed some of our MM selftests for 32-bit machines - Many singleton patches, as usual * tag 'mm-stable-2022-12-13' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (313 commits) mm/hugetlb: set head flag before setting compound_order in __prep_compound_gigantic_folio mm: mmu_gather: allow more than one batch of delayed rmaps mm: fix typo in struct pglist_data code comment kmsan: fix memcpy tests mm: add cond_resched() in swapin_walk_pmd_entry() mm: do not show fs mm pc for VM_LOCKONFAULT pages selftests/vm: ksm_functional_tests: fixes for 32bit selftests/vm: cow: fix compile warning on 32bit selftests/vm: madv_populate: fix missing MADV_POPULATE_(READ|WRITE) definitions mm/gup_test: fix PIN_LONGTERM_TEST_READ with highmem mm,thp,rmap: fix races between updates of subpages_mapcount mm: memcg: fix swapcached stat accounting mm: add nodes= arg to memory.reclaim mm: disable top-tier fallback to reclaim on proactive reclaim selftests: cgroup: make sure reclaim target memcg is unprotected selftests: cgroup: refactor proactive reclaim code to reclaim_until() mm: memcg: fix stale protection of reclaim target memcg mm/mmap: properly unaccount memory on mas_preallocate() failure omfs: remove ->writepage jfs: remove ->writepage ...
| * mm/slub.c: use hotplug_memory_notifier() directlyLiu Shixin2022-11-081-6/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 76ae847497bc52 ("Documentation: raise minimum supported version of GCC to 5.1") updated the minimum gcc version to 5.1. So the problem mentioned in f02c69680088 ("include/linux/memory.h: implement register_hotmemory_notifier()") no longer exist. So we can now switch to use hotplug_memory_notifier() directly rather than register_hotmemory_notifier(). Link: https://lkml.kernel.org/r/20220923033347.3935160-4-liushixin2@huawei.com Signed-off-by: Liu Shixin <liushixin2@huawei.com> Reviewed-by: David Hildenbrand <david@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Cc: Waiman Long <longman@redhat.com> Cc: zefan li <lizefan.x@bytedance.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | Merge tag 'linux-kselftest-kunit-next-6.2-rc1' of ↵Linus Torvalds2022-12-121-1/+2
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest Pull KUnit updates from Shuah Khan: "Several enhancements, fixes, clean-ups, documentation updates, improvements to logging and KTAP compliance of KUnit test output: - log numbers in decimal and hex - parse KTAP compliant test output - allow conditionally exposing static symbols to tests when KUNIT is enabled - make static symbols visible during kunit testing - clean-ups to remove unused structure definition" * tag 'linux-kselftest-kunit-next-6.2-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (29 commits) Documentation: dev-tools: Clarify requirements for result description apparmor: test: make static symbols visible during kunit testing kunit: add macro to allow conditionally exposing static symbols to tests kunit: tool: make parser preserve whitespace when printing test log Documentation: kunit: Fix "How Do I Use This" / "Next Steps" sections kunit: tool: don't include KTAP headers and the like in the test log kunit: improve KTAP compliance of KUnit test output kunit: tool: parse KTAP compliant test output mm: slub: test: Use the kunit_get_current_test() function kunit: Use the static key when retrieving the current test kunit: Provide a static key to check if KUnit is actively running tests kunit: tool: make --json do nothing if --raw_ouput is set kunit: tool: tweak error message when no KTAP found kunit: remove KUNIT_INIT_MEM_ASSERTION macro Documentation: kunit: Remove redundant 'tips.rst' page Documentation: KUnit: reword description of assertions Documentation: KUnit: make usage.rst a superset of tips.rst, remove duplication kunit: eliminate KUNIT_INIT_*_ASSERT_STRUCT macros kunit: tool: remove redundant file.close() call in unit test kunit: tool: unit tests all check parser errors, standardize formatting a bit ...
| * | mm: slub: test: Use the kunit_get_current_test() functionDavid Gow2022-12-121-1/+2
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the newly-added function kunit_get_current_test() instead of accessing current->kunit_test directly. This function uses a static key to return more quickly when KUnit is enabled, but no tests are actively running. There should therefore be a negligible performance impact to enabling the slub KUnit tests. Other than the performance improvement, this should be a no-op. Cc: Oliver Glitta <glittao@gmail.com> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Christoph Lameter <cl@linux.com> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: David Rientjes <rientjes@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: David Gow <davidgow@google.com> Acked-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
* | Merge tag 'random-6.2-rc1-for-linus' of ↵Linus Torvalds2022-12-121-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/crng/random Pull random number generator updates from Jason Donenfeld: - Replace prandom_u32_max() and various open-coded variants of it, there is now a new family of functions that uses fast rejection sampling to choose properly uniformly random numbers within an interval: get_random_u32_below(ceil) - [0, ceil) get_random_u32_above(floor) - (floor, U32_MAX] get_random_u32_inclusive(floor, ceil) - [floor, ceil] Coccinelle was used to convert all current users of prandom_u32_max(), as well as many open-coded patterns, resulting in improvements throughout the tree. I'll have a "late" 6.1-rc1 pull for you that removes the now unused prandom_u32_max() function, just in case any other trees add a new use case of it that needs to converted. According to linux-next, there may be two trivial cases of prandom_u32_max() reintroductions that are fixable with a 's/.../.../'. So I'll have for you a final conversion patch doing that alongside the removal patch during the second week. This is a treewide change that touches many files throughout. - More consistent use of get_random_canary(). - Updates to comments, documentation, tests, headers, and simplification in configuration. - The arch_get_random*_early() abstraction was only used by arm64 and wasn't entirely useful, so this has been replaced by code that works in all relevant contexts. - The kernel will use and manage random seeds in non-volatile EFI variables, refreshing a variable with a fresh seed when the RNG is initialized. The RNG GUID namespace is then hidden from efivarfs to prevent accidental leakage. These changes are split into random.c infrastructure code used in the EFI subsystem, in this pull request, and related support inside of EFISTUB, in Ard's EFI tree. These are co-dependent for full functionality, but the order of merging doesn't matter. - Part of the infrastructure added for the EFI support is also used for an improvement to the way vsprintf initializes its siphash key, replacing an sleep loop wart. - The hardware RNG framework now always calls its correct random.c input function, add_hwgenerator_randomness(), rather than sometimes going through helpers better suited for other cases. - The add_latent_entropy() function has long been called from the fork handler, but is a no-op when the latent entropy gcc plugin isn't used, which is fine for the purposes of latent entropy. But it was missing out on the cycle counter that was also being mixed in beside the latent entropy variable. So now, if the latent entropy gcc plugin isn't enabled, add_latent_entropy() will expand to a call to add_device_randomness(NULL, 0), which adds a cycle counter, without the absent latent entropy variable. - The RNG is now reseeded from a delayed worker, rather than on demand when used. Always running from a worker allows it to make use of the CPU RNG on platforms like S390x, whose instructions are too slow to do so from interrupts. It also has the effect of adding in new inputs more frequently with more regularity, amounting to a long term transcript of random values. Plus, it helps a bit with the upcoming vDSO implementation (which isn't yet ready for 6.2). - The jitter entropy algorithm now tries to execute on many different CPUs, round-robining, in hopes of hitting even more memory latencies and other unpredictable effects. It also will mix in a cycle counter when the entropy timer fires, in addition to being mixed in from the main loop, to account more explicitly for fluctuations in that timer firing. And the state it touches is now kept within the same cache line, so that it's assured that the different execution contexts will cause latencies. * tag 'random-6.2-rc1-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/crng/random: (23 commits) random: include <linux/once.h> in the right header random: align entropy_timer_state to cache line random: mix in cycle counter when jitter timer fires random: spread out jitter callback to different CPUs random: remove extraneous period and add a missing one in comments efi: random: refresh non-volatile random seed when RNG is initialized vsprintf: initialize siphash key using notifier random: add back async readiness notifier random: reseed in delayed work rather than on-demand random: always mix cycle counter in add_latent_entropy() hw_random: use add_hwgenerator_randomness() for early entropy random: modernize documentation comment on get_random_bytes() random: adjust comment to account for removed function random: remove early archrandom abstraction random: use random.trust_{bootloader,cpu} command line option only stackprotector: actually use get_random_canary() stackprotector: move get_random_canary() into stackprotector.h treewide: use get_random_u32_inclusive() when possible treewide: use get_random_u32_{above,below}() instead of manual loop treewide: use get_random_u32_below() instead of deprecated function ...
| * | treewide: use get_random_u32_below() instead of deprecated functionJason A. Donenfeld2022-11-181-1/+1
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This is a simple mechanical transformation done by: @@ expression E; @@ - prandom_u32_max + get_random_u32_below (E) Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Reviewed-by: SeongJae Park <sj@kernel.org> # for damon Reviewed-by: Jason Gunthorpe <jgg@nvidia.com> # for infiniband Reviewed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> # for arm Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* | Merge branch 'slub-tiny-v1r6' into slab/for-nextVlastimil Babka2022-12-011-134/+288
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Merge my series [1] to deprecate the SLOB allocator. - Renames CONFIG_SLOB to CONFIG_SLOB_DEPRECATED with deprecation notice. - The recommended replacement is CONFIG_SLUB, optionally with the new CONFIG_SLUB_TINY tweaks for systems with 16MB or less RAM. - Use cases that stopped working with CONFIG_SLUB_TINY instead of SLOB should be reported to linux-mm@kvack.org and slab maintainers, otherwise SLOB will be removed in few cycles. [1] https://lore.kernel.org/all/20221121171202.22080-1-vbabka@suse.cz/
| * | mm, slub: don't aggressively inline with CONFIG_SLUB_TINYVlastimil Babka2022-12-011-4/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SLUB fastpaths use __always_inline to avoid function calls. With CONFIG_SLUB_TINY we would rather save the memory. Add a __fastpath_inline macro that's __always_inline normally but empty with CONFIG_SLUB_TINY. bloat-o-meter results on x86_64 mm/slub.o: add/remove: 3/1 grow/shrink: 1/8 up/down: 865/-1784 (-919) Function old new delta kmem_cache_free 20 281 +261 slab_alloc_node.isra - 245 +245 slab_free.constprop.isra - 231 +231 __kmem_cache_alloc_lru.isra - 128 +128 __kmem_cache_release 88 83 -5 __kmem_cache_create 1446 1436 -10 __kmem_cache_free 271 142 -129 kmem_cache_alloc_node 330 127 -203 kmem_cache_free_bulk.part 826 613 -213 __kmem_cache_alloc_node 230 10 -220 kmem_cache_alloc_lru 325 12 -313 kmem_cache_alloc 325 10 -315 kmem_cache_free.part 376 - -376 Total: Before=26103, After=25184, chg -3.52% Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
| * | mm, slub: remove percpu slabs with CONFIG_SLUB_TINYVlastimil Babka2022-12-011-3/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SLUB gets most of its scalability by percpu slabs. However for CONFIG_SLUB_TINY the goal is minimal memory overhead, not scalability. Thus, #ifdef out the whole kmem_cache_cpu percpu structure and associated code. Additionally to the slab page savings, this reduces percpu allocator usage, and code size. This change builds on recent commit c7323a5ad078 ("mm/slub: restrict sysfs validation to debug caches and make it safe"), as caches with enabled debugging also avoid percpu slabs and all allocations and freeing ends up working with the partial list. With a bit more refactoring by the preceding patches, use the same code paths with CONFIG_SLUB_TINY. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com>
| * | mm, slub: split out allocations from pre/post hooksVlastimil Babka2022-12-011-50/+80
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the following patch we want to introduce CONFIG_SLUB_TINY allocation paths that don't use the percpu slab. To prepare, refactor the allocation functions: Split out __slab_alloc_node() from slab_alloc_node() where the former does the actual allocation and the latter calls the pre/post hooks. Analogically, split out __kmem_cache_alloc_bulk() from kmem_cache_alloc_bulk(). Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
| * | mm, slub: refactor free debug processingVlastimil Babka2022-11-271-71/+83
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since commit c7323a5ad078 ("mm/slub: restrict sysfs validation to debug caches and make it safe"), caches with debugging enabled use the free_debug_processing() function to do both freeing checks and actual freeing to partial list under list_lock, bypassing the fast paths. We will want to use the same path for CONFIG_SLUB_TINY, but without the debugging checks, so refactor the code so that free_debug_processing() does only the checks, while the freeing is handled by a new function free_to_partial_list(). For consistency, change return parameter alloc_debug_processing() from int to bool and correct the !SLUB_DEBUG variant to return true and not false. This didn't matter until now, but will in the following changes. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
| * | mm, slub: lower the default slub_max_order with CONFIG_SLUB_TINYVlastimil Babka2022-11-271-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With CONFIG_SLUB_TINY we want to minimize memory overhead. By lowering the default slub_max_order we can make slab allocations use smaller pages. However depending on object sizes, order-0 might not be the best due to increased fragmentation. When testing on a 8MB RAM k210 system by Damien Le Moal [1], slub_max_order=1 had the best results, so use that as the default for CONFIG_SLUB_TINY. [1] https://lore.kernel.org/all/6a1883c4-4c3f-545a-90e8-2cd805bcf4ae@opensource.wdc.com/ Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com>
| * | mm, slub: retain no free slabs on partial list with CONFIG_SLUB_TINYVlastimil Babka2022-11-271-0/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SLUB will leave a number of slabs on the partial list even if they are empty, to avoid some slab freeing and reallocation. The goal of CONFIG_SLUB_TINY is to minimize memory overhead, so set the limits to 0 for immediate slab page freeing. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com>
| * | mm, slub: disable SYSFS support with CONFIG_SLUB_TINYVlastimil Babka2022-11-271-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently SLUB enables its sysfs support depending unconditionally on the general CONFIG_SYSFS setting. To reduce the configuration combination space, make CONFIG_SLUB_TINY disable SLUB's sysfs support by reusing the existing SLAB_SUPPORTS_SYSFS define. It is unlikely that real tiny systems would combine CONFIG_SLUB_TINY with CONFIG_SYSFS, but a randconfig might. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com>
| * | mm, slab: ignore hardened usercopy parameters when disabledVlastimil Babka2022-11-271-0/+4
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With CONFIG_HARDENED_USERCOPY not enabled, there are no __check_heap_object() checks happening that would use the struct kmem_cache useroffset and usersize fields. Yet the fields are still initialized, preventing merging of otherwise compatible caches. Also the fields contribute to struct kmem_cache size unnecessarily when unused. Thus #ifdef them out completely when CONFIG_HARDENED_USERCOPY is disabled. In kmem_dump_obj() print object_size instead of usersize, as that's actually the intention. In a quick virtme boot test, this has reduced the number of caches in /proc/slabinfo from 131 to 111. Cc: Kees Cook <keescook@chromium.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Acked-by: Mike Rapoport <rppt@linux.ibm.com> Reviewed-by: Christoph Lameter <cl@linux.com>
* | Merge branch 'slab/for-6.2/kmalloc_redzone' into slab/for-nextVlastimil Babka2022-11-211-10/+54
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kmalloc() redzone improvements by Feng Tang From cover letter [1]: kmalloc's API family is critical for mm, and one of its nature is that it will round up the request size to a fixed one (mostly power of 2). When user requests memory for '2^n + 1' bytes, actually 2^(n+1) bytes could be allocated, so there is an extra space than what is originally requested. This patchset tries to extend the redzone sanity check to the extra kmalloced buffer than requested, to better detect un-legitimate access to it. (depends on SLAB_STORE_USER & SLAB_RED_ZONE) [1] https://lore.kernel.org/all/20221021032405.1825078-1-feng.tang@intel.com/
| * | mm/slub: extend redzone check to extra allocated kmalloc space than requestedFeng Tang2022-11-111-5/+45
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kmalloc will round up the request size to a fixed size (mostly power of 2), so there could be a extra space than what is requested, whose size is the actual buffer size minus original request size. To better detect out of bound access or abuse of this space, add redzone sanity check for it. In current kernel, some kmalloc user already knows the existence of the space and utilizes it after calling 'ksize()' to know the real size of the allocated buffer. So we skip the sanity check for objects which have been called with ksize(), as treating them as legitimate users. Kees Cook is working on sanitizing all these user cases, by using kmalloc_size_roundup() to avoid ambiguous usages. And after this is done, this special handling for ksize() can be removed. In some cases, the free pointer could be saved inside the latter part of object data area, which may overlap the redzone part(for small sizes of kmalloc objects). As suggested by Hyeonggon Yoo, force the free pointer to be in meta data area when kmalloc redzone debug is enabled, to make all kmalloc objects covered by redzone check. Suggested-by: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Feng Tang <feng.tang@intel.com> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
| * | mm: kasan: Extend kasan_metadata_size() to also cover in-object sizeFeng Tang2022-11-101-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When kasan is enabled for slab/slub, it may save kasan' free_meta data in the former part of slab object data area in slab object's free path, which works fine. There is ongoing effort to extend slub's debug function which will redzone the latter part of kmalloc object area, and when both of the debug are enabled, there is possible conflict, especially when the kmalloc object has small size, as caught by 0Day bot [1]. To solve it, slub code needs to know the in-object kasan's meta data size. Currently, there is existing kasan_metadata_size() which returns the kasan's metadata size inside slub's metadata area, so extend it to also cover the in-object meta size by adding a boolean flag 'in_object'. There is no functional change to existing code logic. [1]. https://lore.kernel.org/lkml/YuYm3dWwpZwH58Hu@xsang-OptiPlex-9020/ Reported-by: kernel test robot <oliver.sang@intel.com> Suggested-by: Andrey Konovalov <andreyknvl@gmail.com> Signed-off-by: Feng Tang <feng.tang@intel.com> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
| * | mm/slub: only zero requested size of buffer for kzalloc when debug enabledFeng Tang2022-11-101-3/+7
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kzalloc/kmalloc will round up the request size to a fixed size (mostly power of 2), so the allocated memory could be more than requested. Currently kzalloc family APIs will zero all the allocated memory. To detect out-of-bound usage of the extra allocated memory, only zero the requested part, so that redzone sanity check could be added to the extra space later. For kzalloc users who will call ksize() later and utilize this extra space, please be aware that the space is not zeroed any more when debug is enabled. (Thanks to Kees Cook's effort to sanitize all ksize() user cases [1], this won't be a big issue). [1]. https://lore.kernel.org/all/20220922031013.2150682-1-keescook@chromium.org/#r Signed-off-by: Feng Tang <feng.tang@intel.com> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* | Merge branch 'slab/for-6.2/fit_rcu_head' into slab/for-nextVlastimil Babka2022-11-211-11/+15
|\ \ | | | | | | | | | | | | | | | | | | | | | A series by myself to reorder fields in struct slab to allow the embedded rcu_head to grow (for debugging purposes). Requires changes to isolate_movable_page() to skip slab pages which can otherwise become false-positive __PageMovable due to its use of low bits in page->mapping.
| * | mm/migrate: make isolate_movable_page() skip slab pagesVlastimil Babka2022-11-211-1/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In the next commit we want to rearrange struct slab fields to allow a larger rcu_head. Afterwards, the page->mapping field will overlap with SLUB's "struct list_head slab_list", where the value of prev pointer can become LIST_POISON2, which is 0x122 + POISON_POINTER_DELTA. Unfortunately the bit 1 being set can confuse PageMovable() to be a false positive and cause a GPF as reported by lkp [1]. To fix this, make isolate_movable_page() skip pages with the PageSlab flag set. This is a bit tricky as we need to add memory barriers to SLAB and SLUB's page allocation and freeing, and their counterparts to isolate_movable_page(). Based on my RFC from [2]. Added a comment update from Matthew's variant in [3] and, as done there, moved the PageSlab checks to happen before trying to take the page lock. [1] https://lore.kernel.org/all/208c1757-5edd-fd42-67d4-1940cc43b50f@intel.com/ [2] https://lore.kernel.org/all/aec59f53-0e53-1736-5932-25407125d4d4@suse.cz/ [3] https://lore.kernel.org/all/YzsVM8eToHUeTP75@casper.infradead.org/ Reported-by: kernel test robot <yujie.liu@intel.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
| * | mm/slub: perform free consistency checks before call_rcuVlastimil Babka2022-10-241-10/+10
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | For SLAB_TYPESAFE_BY_RCU caches we use call_rcu to perform empty slab freeing. The rcu callback rcu_free_slab() calls __free_slab() that currently includes checking the slab consistency for caches with SLAB_CONSISTENCY_CHECKS flags. This check needs the slab->objects field to be intact. Because in the next patch we want to allow rcu_head in struct slab to become larger in debug configurations and thus potentially overwrite more fields through a union than slab_list, we want to limit the fields used in rcu_free_slab(). Thus move the consistency checks to free_slab() before call_rcu(). This can be done safely even for SLAB_TYPESAFE_BY_RCU caches where accesses to the objects can still occur after freeing them. As a result, only the slab->slab_cache field has to be physically separate from rcu_head for the freeing callback to work. We also save some cycles in the rcu callback for caches with consistency checks enabled. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com>
* | Merge branch 'slab/for-6.2/slub-sysfs' into slab/for-nextVlastimil Babka2022-11-211-8/+16
|\ \ | | | | | | | | | | | | | | | | | | - Two patches for SLUB's sysfs by Rasmus Villemoes to remove dead code and optimize boot time with late initialization. - Allow SLUB's sysfs 'failslab' parameter to be runtime-controllable again as it can be both useful and safe, by Alexander Atanasov.
| * | mm: Make failslab writable againAlexander Atanasov2022-10-241-1/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In (060807f841ac mm, slub: make remaining slub_debug related attributes read-only) failslab was made read-only. I think it became a collateral victim to the two other options for which the reasons are perfectly valid. Here is why: - sanity_checks and trace are slab internal debug options, failslab is used for fault injection. - for fault injections, which by presumption are random, it does not matter if it is not set atomically. And you need to set atleast one more option to trigger fault injection. - in a testing scenario you may need to change it at runtime example: module loading - you test all allocations limited by the space option. Then you move to test only your module's own slabs. - when set by command line flags it effectively disables all cache merges. Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Kees Cook <keescook@chromium.org> Cc: Roman Gushchin <guro@fb.com> Cc: Christoph Lameter <cl@linux.com> Cc: Jann Horn <jannh@google.com> Cc: Vijayanand Jitta <vjitta@codeaurora.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Link: http://lkml.kernel.org/r/20200610163135.17364-5-vbabka@suse.cz Signed-off-by: Alexander Atanasov <alexander.atanasov@virtuozzo.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
| * | mm: slub: make slab_sysfs_init() a late_initcallRasmus Villemoes2022-10-241-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently, slab_sysfs_init() is an __initcall aka device_initcall. It is rather time-consuming; on my board it takes around 11ms. That's about 1% of the time budget I have from U-Boot letting go and until linux must assume responsibility of keeping the external watchdog happy. There's no particular reason this would need to run at device_initcall time, so instead make it a late_initcall to allow vital functionality to get started a bit sooner. This actually ends up winning more than just those 11ms, because the slab caches that get created during other device_initcalls (and before my watchdog device gets probed) now don't end up doing the somewhat expensive sysfs_slab_add() themselves. Some example lines (with initcall_debug set) before/after: initcall ext4_init_fs+0x0/0x1ac returned 0 after 1386 usecs initcall journal_init+0x0/0x138 returned 0 after 517 usecs initcall init_fat_fs+0x0/0x68 returned 0 after 294 usecs initcall ext4_init_fs+0x0/0x1ac returned 0 after 240 usecs initcall journal_init+0x0/0x138 returned 0 after 32 usecs initcall init_fat_fs+0x0/0x68 returned 0 after 18 usecs Altogether, this means I now get to petting the watchdog around 17ms sooner. [Of course, the time the other initcalls save is instead spent in slab_sysfs_init(), which goes from 11ms to 16ms, so there's no overall change in boot time.] Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
| * | mm: slub: remove dead and buggy code from sysfs_slab_add()Rasmus Villemoes2022-10-241-5/+0
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The function sysfs_slab_add() has two callers: One is slab_sysfs_init(), which first initializes slab_kset, and only when that succeeds sets slab_state to FULL, and then proceeds to call sysfs_slab_add() for all previously created slabs. The other is __kmem_cache_create(), but only after a if (slab_state <= UP) return 0; check. So in other words, sysfs_slab_add() is never called without slab_kset (aka the return value of cache_kset()) being non-NULL. And this is just as well, because if we ever did take this path and called kobject_init(&s->kobj), and then later when called again from slab_sysfs_init() would end up calling kobject_init_and_add(), we would hit if (kobj->state_initialized) { /* do not error out as sometimes we can recover */ pr_err("kobject (%p): tried to init an initialized object, something is seriously wrong.\n", dump_stack(); } in kobject.c. Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: David Rientjes <rientjes@google.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* | mm/slub, percpu: correct the calculation of early percpu allocation sizeBaoquan He2022-11-211-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | SLUB allocator relies on percpu allocator to initialize its ->cpu_slab during early boot. For that, the dynamic chunk of percpu which serves the early allocation need be large enough to satisfy the kmalloc creation. However, the current BUILD_BUG_ON() in alloc_kmem_cache_cpus() doesn't consider the kmalloc array with NR_KMALLOC_TYPES length. Fix that with correct calculation. Signed-off-by: Baoquan He <bhe@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: Dennis Zhou <dennis@kernel.org> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* | mm/slub: remove dead code for debug caches on deactivate_slab()Hyeonggon Yoo2022-10-241-14/+2
|/ | | | | | | | | | | | After commit c7323a5ad0786 ("mm/slub: restrict sysfs validation to debug caches and make it safe"), SLUB never installs percpu slab for debug caches and thus never deactivates percpu slab for them. Since only debug caches use the full list, SLUB no longer deactivates to full list. Remove dead code in deactivate_slab(). Signed-off-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* treewide: use prandom_u32_max() when possible, part 1Jason A. Donenfeld2022-10-111-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done mechanically with this coccinelle script: @basic@ expression E; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; typedef u64; @@ ( - ((T)get_random_u32() % (E)) + prandom_u32_max(E) | - ((T)get_random_u32() & ((E) - 1)) + prandom_u32_max(E * XXX_MAKE_SURE_E_IS_POW2) | - ((u64)(E) * get_random_u32() >> 32) + prandom_u32_max(E) | - ((T)get_random_u32() & ~PAGE_MASK) + prandom_u32_max(PAGE_SIZE) ) @multi_line@ identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; identifier RAND; expression E; @@ - RAND = get_random_u32(); ... when != RAND - RAND %= (E); + RAND = prandom_u32_max(E); // Find a potential literal @literal_mask@ expression LITERAL; type T; identifier get_random_u32 =~ "get_random_int|prandom_u32|get_random_u32"; position p; @@ ((T)get_random_u32()@p & (LITERAL)) // Add one to the literal. @script:python add_one@ literal << literal_mask.LITERAL; RESULT; @@ value = None if literal.startswith('0x'): value = int(literal, 16) elif literal[0] in '123456789': value = int(literal, 10) if value is None: print("I don't know how to handle %s" % (literal)) cocci.include_match(False) elif value == 2**32 - 1 or value == 2**31 - 1 or value == 2**24 - 1 or value == 2**16 - 1 or value == 2**8 - 1: print("Skipping 0x%x for cleanup elsewhere" % (value)) cocci.include_match(False) elif value & (value + 1) != 0: print("Skipping 0x%x because it's not a power of two minus one" % (value)) cocci.include_match(False) elif literal.startswith('0x'): coccinelle.RESULT = cocci.make_expr("0x%x" % (value + 1)) else: coccinelle.RESULT = cocci.make_expr("%d" % (value + 1)) // Replace the literal mask with the calculated result. @plus_one@ expression literal_mask.LITERAL; position literal_mask.p; expression add_one.RESULT; identifier FUNC; @@ - (FUNC()@p & (LITERAL)) + prandom_u32_max(RESULT) @collapse_ret@ type T; identifier VAR; expression E; @@ { - T VAR; - VAR = (E); - return VAR; + return E; } @drop_var@ type T; identifier VAR; @@ { - T VAR; ... when != VAR } Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: KP Singh <kpsingh@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 and sbitmap Reviewed-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com> # for drbd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Acked-by: Ulf Hansson <ulf.hansson@linaro.org> # for mmc Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
* Merge tag 'mm-stable-2022-10-08' of ↵Linus Torvalds2022-10-101-0/+41
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Yu Zhao's Multi-Gen LRU patches are here. They've been under test in linux-next for a couple of months without, to my knowledge, any negative reports (or any positive ones, come to that). - Also the Maple Tree from Liam Howlett. An overlapping range-based tree for vmas. It it apparently slightly more efficient in its own right, but is mainly targeted at enabling work to reduce mmap_lock contention. Liam has identified a number of other tree users in the kernel which could be beneficially onverted to mapletrees. Yu Zhao has identified a hard-to-hit but "easy to fix" lockdep splat at [1]. This has yet to be addressed due to Liam's unfortunately timed vacation. He is now back and we'll get this fixed up. - Dmitry Vyukov introduces KMSAN: the Kernel Memory Sanitizer. It uses clang-generated instrumentation to detect used-unintialized bugs down to the single bit level. KMSAN keeps finding bugs. New ones, as well as the legacy ones. - Yang Shi adds a userspace mechanism (madvise) to induce a collapse of memory into THPs. - Zach O'Keefe has expanded Yang Shi's madvise(MADV_COLLAPSE) to support file/shmem-backed pages. - userfaultfd updates from Axel Rasmussen - zsmalloc cleanups from Alexey Romanov - cleanups from Miaohe Lin: vmscan, hugetlb_cgroup, hugetlb and memory-failure - Huang Ying adds enhancements to NUMA balancing memory tiering mode's page promotion, with a new way of detecting hot pages. - memcg updates from Shakeel Butt: charging optimizations and reduced memory consumption. - memcg cleanups from Kairui Song. - memcg fixes and cleanups from Johannes Weiner. - Vishal Moola provides more folio conversions - Zhang Yi removed ll_rw_block() :( - migration enhancements from Peter Xu - migration error-path bugfixes from Huang Ying - Aneesh Kumar added ability for a device driver to alter the memory tiering promotion paths. For optimizations by PMEM drivers, DRM drivers, etc. - vma merging improvements from Jakub Matěn. - NUMA hinting cleanups from David Hildenbrand. - xu xin added aditional userspace visibility into KSM merging activity. - THP & KSM code consolidation from Qi Zheng. - more folio work from Matthew Wilcox. - KASAN updates from Andrey Konovalov. - DAMON cleanups from Kaixu Xia. - DAMON work from SeongJae Park: fixes, cleanups. - hugetlb sysfs cleanups from Muchun Song. - Mike Kravetz fixes locking issues in hugetlbfs and in hugetlb core. Link: https://lkml.kernel.org/r/CAOUHufZabH85CeUN-MEMgL8gJGzJEWUrkiM58JkTbBhh-jew0Q@mail.gmail.com [1] * tag 'mm-stable-2022-10-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (555 commits) hugetlb: allocate vma lock for all sharable vmas hugetlb: take hugetlb vma_lock when clearing vma_lock->vma pointer hugetlb: fix vma lock handling during split vma and range unmapping mglru: mm/vmscan.c: fix imprecise comments mm/mglru: don't sync disk for each aging cycle mm: memcontrol: drop dead CONFIG_MEMCG_SWAP config symbol mm: memcontrol: use do_memsw_account() in a few more places mm: memcontrol: deprecate swapaccounting=0 mode mm: memcontrol: don't allocate cgroup swap arrays when memcg is disabled mm/secretmem: remove reduntant return value mm/hugetlb: add available_huge_pages() func mm: remove unused inline functions from include/linux/mm_inline.h selftests/vm: add selftest for MADV_COLLAPSE of uffd-minor memory selftests/vm: add file/shmem MADV_COLLAPSE selftest for cleared pmd selftests/vm: add thp collapse shmem testing selftests/vm: add thp collapse file and tmpfs testing selftests/vm: modularize thp collapse memory operations selftests/vm: dedup THP helpers mm/khugepaged: add tracepoint to hpage_collapse_scan_file() mm/madvise: add file and shmem support to MADV_COLLAPSE ...
| * mm: kmsan: call KMSAN hooks from SLUB codeAlexander Potapenko2022-10-031-0/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | In order to report uninitialized memory coming from heap allocations KMSAN has to poison them unless they're created with __GFP_ZERO. It's handy that we need KMSAN hooks in the places where init_on_alloc/init_on_free initialization is performed. In addition, we apply __no_kmsan_checks to get_freepointer_safe() to suppress reports when accessing freelist pointers that reside in freed objects. Link: https://lkml.kernel.org/r/20220915150417.722975-16-glider@google.com Signed-off-by: Alexander Potapenko <glider@google.com> Reviewed-by: Marco Elver <elver@google.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Andrey Konovalov <andreyknvl@gmail.com> Cc: Andrey Konovalov <andreyknvl@google.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Borislav Petkov <bp@alien8.de> Cc: Christoph Hellwig <hch@lst.de> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers@google.com> Cc: Eric Biggers <ebiggers@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: Ilya Leoshkevich <iii@linux.ibm.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jens Axboe <axboe@kernel.dk> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Kees Cook <keescook@chromium.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: Michael S. Tsirkin <mst@redhat.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Petr Mladek <pmladek@suse.com> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| * kfence: add sysfs interface to disable kfence for selected slabs.Imran Khan2022-09-111-0/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | By default kfence allocation can happen for any slab object, whose size is up to PAGE_SIZE, as long as that allocation is the first allocation after expiration of kfence sample interval. But in certain debugging scenarios we may be interested in debugging corruptions involving some specific slub objects like dentry or ext4_* etc. In such cases limiting kfence for allocations involving only specific slub objects will increase the probablity of catching the issue since kfence pool will not be consumed by other slab objects. This patch introduces a sysfs interface '/sys/kernel/slab/<name>/skip_kfence' to disable kfence for specific slabs. Having the interface work in this way does not impact current/default behavior of kfence and allows us to use kfence for specific slabs (when needed) as well. The decision to skip/use kfence is taken depending on whether kmem_cache.flags has (newly introduced) SLAB_SKIP_KFENCE flag set or not. Link: https://lkml.kernel.org/r/20220814195353.2540848-1-imran.f.khan@oracle.com Signed-off-by: Imran Khan <imran.f.khan@oracle.com> Reviewed-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Marco Elver <elver@google.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Alexander Potapenko <glider@google.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Christoph Lameter <cl@linux.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Roman Gushchin <roman.gushchin@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
* | Merge branch 'slab/for-6.1/slub_validation_locking' into slab/for-nextVlastimil Babka2022-09-301-11/+14
|\ \ | | | | | | | | | | | | A fix for a regression in slub_debug caches that could cause slab page leaks and subsequent warnings on cache shutdown, by Feng Tang.
| * | mm/slub: fix a slab missed to be freed problemFeng Tang2022-09-301-11/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When enable kasan and kfence's in-kernel kunit test with slub_debug on, it caught a problem (in linux-next tree): ------------[ cut here ]------------ kmem_cache_destroy test: Slab cache still has objects when called from test_exit+0x1a/0x30 WARNING: CPU: 3 PID: 240 at mm/slab_common.c:492 kmem_cache_destroy+0x16c/0x170 Modules linked in: CPU: 3 PID: 240 Comm: kunit_try_catch Tainted: G B N 6.0.0-rc7-next-20220929 #52 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:kmem_cache_destroy+0x16c/0x170 Code: 41 5c 41 5d e9 a5 04 0b 00 c3 cc cc cc cc 48 8b 55 60 48 8b 4c 24 20 48 c7 c6 40 37 d2 82 48 c7 c7 e8 a0 33 83 e8 4e d7 14 01 <0f> 0b eb a7 41 56 41 89 d6 41 55 49 89 f5 41 54 49 89 fc 55 48 89 RSP: 0000:ffff88800775fea0 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffffffff83bdec48 RCX: 0000000000000000 RDX: 0000000000000001 RSI: 1ffff11000eebf9e RDI: ffffed1000eebfc6 RBP: ffff88804362fa00 R08: ffffffff81182e58 R09: ffff88800775fbdf R10: ffffed1000eebf7b R11: 0000000000000001 R12: 000000008c800d00 R13: ffff888005e78040 R14: 0000000000000000 R15: ffff888005cdfad0 FS: 0000000000000000(0000) GS:ffff88807ed00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000000360e001 CR4: 0000000000370ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> test_exit+0x1a/0x30 kunit_try_run_case+0xad/0xc0 kunit_generic_run_threadfn_adapter+0x26/0x50 kthread+0x17b/0x1b0 It was biscted to commit c7323a5ad078 ("mm/slub: restrict sysfs validation to debug caches and make it safe") The problem is inside free_debug_processing(), under certain circumstances the slab can be removed from the partial list but not freed by discard_slab() and thus n->nr_slabs is not decreased accordingly. During shutdown, this non-zero n->nr_slabs is detected and reported. Specifically, the problem is that there are two checks for detecting a full partial list by comparing n->nr_partial >= s->min_partial where the latter check is affected by remove_partial() decreasing n->nr_partial between the checks. Reoganize the code so there is a single check upfront. Link: https://lore.kernel.org/all/20220930100730.250248-1-feng.tang@intel.com/ Fixes: c7323a5ad078 ("mm/slub: restrict sysfs validation to debug caches and make it safe") Signed-off-by: Feng Tang <feng.tang@intel.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* | | Merge branch 'slab/for-6.1/slub_debug_waste' into slab/for-nextVlastimil Babka2022-09-291-37/+117
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | A patch from Feng Tang that enhances the existing debugfs alloc_traces file for kmalloc caches with information about how much space is wasted by allocations that needs less space than the particular kmalloc cache provides.
| * | | mm/slub: enable debugging memory wasting of kmallocFeng Tang2022-09-231-37/+117
| |/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | kmalloc's API family is critical for mm, with one nature that it will round up the request size to a fixed one (mostly power of 2). Say when user requests memory for '2^n + 1' bytes, actually 2^(n+1) bytes could be allocated, so in worst case, there is around 50% memory space waste. The wastage is not a big issue for requests that get allocated/freed quickly, but may cause problems with objects that have longer life time. We've met a kernel boot OOM panic (v5.10), and from the dumped slab info: [ 26.062145] kmalloc-2k 814056KB 814056KB From debug we found there are huge number of 'struct iova_magazine', whose size is 1032 bytes (1024 + 8), so each allocation will waste 1016 bytes. Though the issue was solved by giving the right (bigger) size of RAM, it is still nice to optimize the size (either use a kmalloc friendly size or create a dedicated slab for it). And from lkml archive, there was another crash kernel OOM case [1] back in 2019, which seems to be related with the similar slab waste situation, as the log is similar: [ 4.332648] iommu: Adding device 0000:20:02.0 to group 16 [ 4.338946] swapper/0 invoked oom-killer: gfp_mask=0x6040c0(GFP_KERNEL|__GFP_COMP), nodemask=(null), order=0, oom_score_adj=0 ... [ 4.857565] kmalloc-2048 59164KB 59164KB The crash kernel only has 256M memory, and 59M is pretty big here. (Note: the related code has been changed and optimised in recent kernel [2], these logs are just picked to demo the problem, also a patch changing its size to 1024 bytes has been merged) So add an way to track each kmalloc's memory waste info, and leverage the existing SLUB debug framework (specifically SLUB_STORE_USER) to show its call stack of original allocation, so that user can evaluate the waste situation, identify some hot spots and optimize accordingly, for a better utilization of memory. The waste info is integrated into existing interface: '/sys/kernel/debug/slab/kmalloc-xx/alloc_traces', one example of 'kmalloc-4k' after boot is: 126 ixgbe_alloc_q_vector+0xbe/0x830 [ixgbe] waste=233856/1856 age=280763/281414/282065 pid=1330 cpus=32 nodes=1 __kmem_cache_alloc_node+0x11f/0x4e0 __kmalloc_node+0x4e/0x140 ixgbe_alloc_q_vector+0xbe/0x830 [ixgbe] ixgbe_init_interrupt_scheme+0x2ae/0xc90 [ixgbe] ixgbe_probe+0x165f/0x1d20 [ixgbe] local_pci_probe+0x78/0xc0 work_for_cpu_fn+0x26/0x40 ... which means in 'kmalloc-4k' slab, there are 126 requests of 2240 bytes which got a 4KB space (wasting 1856 bytes each and 233856 bytes in total), from ixgbe_alloc_q_vector(). And when system starts some real workload like multiple docker instances, there could are more severe waste. [1]. https://lkml.org/lkml/2019/8/12/266 [2]. https://lore.kernel.org/lkml/2920df89-9975-5785-f79b-257d3052dfaf@huawei.com/ [Thanks Hyeonggon for pointing out several bugs about sorting/format] [Thanks Vlastimil for suggesting way to reduce memory usage of orig_size and keep it only for kmalloc objects] Signed-off-by: Feng Tang <feng.tang@intel.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Robin Murphy <robin.murphy@arm.com> Cc: John Garry <john.garry@huawei.com> Cc: Kefeng Wang <wangkefeng.wang@huawei.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* | | Merge branch 'slab/for-6.1/trivial' into slab/for-nextVlastimil Babka2022-09-291-3/+6
|\ \ \ | | | | | | | | | | | | Additional cleanup by Chao Yu removing a BUG_ON() in create_unique_id().
| * | | mm/slub: clean up create_unique_id()Chao Yu2022-09-261-3/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | As Christophe JAILLET suggested [1] In create_unique_id(), "looks that ID_STR_LENGTH could even be reduced to 32 or 16. The 2nd BUG_ON at the end of the function could certainly be just removed as well or remplaced by a: if (p > name + ID_STR_LENGTH - 1) { kfree(name); return -E<something>; } " According to above suggestion, let's do below cleanups: 1. reduce ID_STR_LENGTH to 32, as the buffer size should be enough; 2. use WARN_ON instead of BUG_ON() and return error if check condition is true; 3. use snprintf instead of sprintf to avoid overflow. [1] https://lore.kernel.org/linux-mm/2025305d-16db-abdf-6cd3-1fb93371c2b4@wanadoo.fr/ Suggested-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Chao Yu <chao.yu@oppo.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
* | | | Merge branch 'slab/for-6.1/slub_validation_locking' into slab/for-nextVlastimil Babka2022-09-231-198/+276
|\ \ \ \ | | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | My series [1] to fix validation races for caches with enabled debugging. By decoupling the debug cache operation more from non-debug fastpaths, additional locking simplifications were possible and done afterwards. Additional cleanup of PREEMPT_RT specific code on top, by Thomas Gleixner. [1] https://lore.kernel.org/all/20220823170400.26546-1-vbabka@suse.cz/
| * | | slub: Make PREEMPT_RT support less convolutedThomas Gleixner2022-09-171-32/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The slub code already has a few helpers depending on PREEMPT_RT. Add a few more and get rid of the CONFIG_PREEMPT_RT conditionals all over the place. No functional change. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Christoph Lameter <cl@linux.com> Cc: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Cc: Pekka Enberg <penberg@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: linux-mm@kvack.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
| * | | mm/slub: simplify __cmpxchg_double_slab() and slab_[un]lock()Vlastimil Babka2022-09-171-27/+12
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The PREEMPT_RT specific disabling of irqs in __cmpxchg_double_slab() (through slab_[un]lock()) is unnecessary as bit_spin_lock() disables preemption and that's sufficient on PREEMPT_RT where no allocation/free operation is performed in hardirq context and so can't interrupt the current operation. That means we no longer need the slab_[un]lock() wrappers, so delete them and rename the current __slab_[un]lock() to slab_[un]lock(). Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
| * | | mm/slub: convert object_map_lock to non-raw spinlockVlastimil Babka2022-09-171-30/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The only remaining user of object_map_lock is list_slab_objects(). Obtaining the lock there used to happen under slab_lock() which implied disabling irqs on PREEMPT_RT, thus it's a raw_spinlock. With the slab_lock() removed, we can convert it to a normal spinlock. Also remove the get_map()/put_map() wrappers as list_slab_objects() became their only remaining user. Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Acked-by: David Rientjes <rientjes@google.com> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
| * | | mm/slub: remove slab_lock() usage for debug operationsVlastimil Babka2022-09-171-11/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All alloc and free operations on debug caches are now serialized by n->list_lock, so we can remove slab_lock() usage in validate_slab() and list_slab_objects() as those also happen under n->list_lock. Note the usage in list_slab_objects() could happen even on non-debug caches, but only during cache shutdown time, so there should not be any parallel freeing activity anymore. Except for buggy slab users, but in that case the slab_lock() would not help against the common cmpxchg based fast paths (in non-debug caches) anyway. Also adjust documentation comments accordingly. Suggested-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Signed-off-by: Vlastimil Babka <vbabka@suse.cz> Reviewed-by: Hyeonggon Yoo <42.hyeyoo@gmail.com> Acked-by: David Rientjes <rientjes@google.com>
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-02 14:17:43 +0000