linux-dev/Documentation/vm, branch master

docs: rename Documentation/vm to Documentation/mm

2022-06-27T19:52:53Z

so it will be consistent with code mm directory and with Documentation/admin-guide/mm and won't be confused with virtual machines. Signed-off-by: Mike Rapoport Suggested-by: Matthew Wilcox Tested-by: Ira Weiny Acked-by: Jonathan Corbet Acked-by: Wu XiangCheng

mm/memory-failure: disable unpoison once hw error happens

2022-06-17T02:11:32Z

Currently unpoison_memory(unsigned long pfn) is designed for soft poison(hwpoison-inject) only. Since 17fae1294ad9d, the KPTE gets cleared on a x86 platform once hardware memory corrupts. Unpoisoning a hardware corrupted page puts page back buddy only, the kernel has a chance to access the page with *NOT PRESENT* KPTE. This leads BUG during accessing on the corrupted KPTE. Suggested by David&Naoya, disable unpoison mechanism when a real HW error happens to avoid BUG like this: Unpoison: Software-unpoisoned page 0x61234 BUG: unable to handle page fault for address: ffff888061234000 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 2c01067 P4D 2c01067 PUD 107267063 PMD 10382b063 PTE 800fffff9edcb062 Oops: 0002 [#1] PREEMPT SMP NOPTI CPU: 4 PID: 26551 Comm: stress Kdump: loaded Tainted: G M OE 5.18.0.bm.1-amd64 #7 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) ... RIP: 0010:clear_page_erms+0x7/0x10 Code: ... RSP: 0000:ffffc90001107bc8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000901 RCX: 0000000000001000 RDX: ffffea0001848d00 RSI: ffffea0001848d40 RDI: ffff888061234000 RBP: ffffea0001848d00 R08: 0000000000000901 R09: 0000000000001276 R10: 0000000000000003 R11: 0000000000000000 R12: 0000000000000001 R13: 0000000000000000 R14: 0000000000140dca R15: 0000000000000001 FS: 00007fd8b2333740(0000) GS:ffff88813fd00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888061234000 CR3: 00000001023d2005 CR4: 0000000000770ee0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: prep_new_page+0x151/0x170 get_page_from_freelist+0xca0/0xe20 ? sysvec_apic_timer_interrupt+0xab/0xc0 ? asm_sysvec_apic_timer_interrupt+0x1b/0x20 __alloc_pages+0x17e/0x340 __folio_alloc+0x17/0x40 vma_alloc_folio+0x84/0x280 __handle_mm_fault+0x8d4/0xeb0 handle_mm_fault+0xd5/0x2a0 do_user_addr_fault+0x1d0/0x680 ? kvm_read_and_reset_apf_flags+0x3b/0x50 exc_page_fault+0x78/0x170 asm_exc_page_fault+0x27/0x30 Link: https://lkml.kernel.org/r/20220615093209.259374-2-pizhenwei@bytedance.com Fixes: 847ce401df392 ("HWPOISON: Add unpoisoning support") Fixes: 17fae1294ad9d ("x86/{mce,mm}: Unmap the entire page if the whole page is affected and poisoned") Signed-off-by: zhenwei pi Acked-by: David Hildenbrand Acked-by: Naoya Horiguchi Reviewed-by: Miaohe Lin Reviewed-by: Oscar Salvador Cc: Greg Kroah-Hartman Cc: [5.8+] Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2022-05-26T19:32:41Z

Pull MM updates from Andrew Morton: "Almost all of MM here. A few things are still getting finished off, reviewed, etc. - Yang Shi has improved the behaviour of khugepaged collapsing of readonly file-backed transparent hugepages. - Johannes Weiner has arranged for zswap memory use to be tracked and managed on a per-cgroup basis. - Munchun Song adds a /proc knob ("hugetlb_optimize_vmemmap") for runtime enablement of the recent huge page vmemmap optimization feature. - Baolin Wang contributes a series to fix some issues around hugetlb pagetable invalidation. - Zhenwei Pi has fixed some interactions between hwpoisoned pages and virtualization. - Tong Tiangen has enabled the use of the presently x86-only page_table_check debugging feature on arm64 and riscv. - David Vernet has done some fixup work on the memcg selftests. - Peter Xu has taught userfaultfd to handle write protection faults against shmem- and hugetlbfs-backed files. - More DAMON development from SeongJae Park - adding online tuning of the feature and support for monitoring of fixed virtual address ranges. Also easier discovery of which monitoring operations are available. - Nadav Amit has done some optimization of TLB flushing during mprotect(). - Neil Brown continues to labor away at improving our swap-over-NFS support. - David Hildenbrand has some fixes to anon page COWing versus get_user_pages(). - Peng Liu fixed some errors in the core hugetlb code. - Joao Martins has reduced the amount of memory consumed by device-dax's compound devmaps. - Some cleanups of the arch-specific pagemap code from Anshuman Khandual. - Muchun Song has found and fixed some errors in the TLB flushing of transparent hugepages. - Roman Gushchin has done more work on the memcg selftests. ... and, of course, many smaller fixes and cleanups. Notably, the customary million cleanup serieses from Miaohe Lin" * tag 'mm-stable-2022-05-25' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (381 commits) mm: kfence: use PAGE_ALIGNED helper selftests: vm: add the "settings" file with timeout variable selftests: vm: add "test_hmm.sh" to TEST_FILES selftests: vm: check numa_available() before operating "merge_across_nodes" in ksm_tests selftests: vm: add migration to the .gitignore selftests/vm/pkeys: fix typo in comment ksm: fix typo in comment selftests: vm: add process_mrelease tests Revert "mm/vmscan: never demote for memcg reclaim" mm/kfence: print disabling or re-enabling message include/trace/events/percpu.h: cleanup for "percpu: improve percpu_alloc_percpu event trace" include/trace/events/mmflags.h: cleanup for "tracing: incorrect gfp_t conversion" mm: fix a potential infinite loop in start_isolate_page_range() MAINTAINERS: add Muchun as co-maintainer for HugeTLB zram: fix Kconfig dependency warning mm/shmem: fix shmem folio swapoff hang cgroup: fix an error handling path in alloc_pagecache_max_30M() mm: damon: use HPAGE_PMD_SIZE tracing: incorrect isolate_mote_t cast in mm_vmscan_lru_isolate nodemask.h: fix compilation error with GCC12 ...

Merge tag 'docs-5.19' of git://git.lwn.net/linux

2022-05-25T18:17:41Z

Pull documentation updates from Jonathan Corbet: "It was a moderately busy cycle for documentation; highlights include: - After a long period of inactivity, the Japanese translations are seeing some much-needed maintenance and updating. - Reworked IOMMU documentation - Some new documentation for static-analysis tools - A new overall structure for the memory-management documentation. This is an LSFMM outcome that, it is hoped, will help encourage developers to fill in the many gaps. Optimism is eternal...but hopefully it will work. - More Chinese translations. Plus the usual typo fixes, updates, etc" * tag 'docs-5.19' of git://git.lwn.net/linux: (70 commits) docs: pdfdocs: Add space for chapter counts >= 100 in TOC docs/zh_CN: Add dev-tools/gdb-kernel-debugging.rst Chinese translation input: Docs: correct ntrig.rst typo input: Docs: correct atarikbd.rst typos MAINTAINERS: Become the docs/zh_CN maintainer docs/zh_CN: fix devicetree usage-model translation mm,doc: Add new documentation structure Documentation: drop more IDE boot options and ide-cd.rst Documentation/process: use scripts/get_maintainer.pl on patches MAINTAINERS: Add entry for DOCUMENTATION/JAPANESE docs/trans/ja_JP/howto: Don't mention specific kernel versions docs/ja_JP/SubmittingPatches: Request summaries for commit references docs/ja_JP/SubmittingPatches: Add Suggested-by as a standard signature docs/ja_JP/SubmittingPatches: Randy has moved docs/ja_JP/SubmittingPatches: Suggest the use of scripts/get_maintainer.pl docs/ja_JP/SubmittingPatches: Update GregKH links Documentation/sysctl: document max_rcu_stall_to_panic Documentation: add missing angle bracket in cgroup-v2 doc Documentation: dev-tools: use literal block instead of code-block docs/zh_CN: add vm numa translation ...

Merge tag 'slab-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab

2022-05-25T17:24:04Z

Pull slab updates from Vlastimil Babka: - Conversion of slub_debug stack traces to stackdepot, allowing more useful debugfs-based inspection for e.g. memory leak debugging. Allocation and free debugfs info now includes full traces and is sorted by the unique trace frequency. The stackdepot conversion was already attempted last year but reverted by ae14c63a9f20. The memory overhead (while not actually enabled on boot) has been meanwhile solved by making the large stackdepot allocation dynamic. The xfstest issues haven't been reproduced on current kernel locally nor in -next, so the slab cache layout changes that originally made that bug manifest were probably not the root cause. - Refactoring of dma-kmalloc caches creation. - Trivial cleanups such as removal of unused parameters, fixes and clarifications of comments. - Hyeonggon Yoo joins as a reviewer. * tag 'slab-for-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/vbabka/slab: MAINTAINERS: add myself as reviewer for slab mm/slub: remove unused kmem_cache_order_objects max mm: slab: fix comment for __assume_kmalloc_alignment mm: slab: fix comment for ARCH_KMALLOC_MINALIGN mm/slub: remove unneeded return value of slab_pad_check mm/slab_common: move dma-kmalloc caches creation into new_kmalloc_cache() mm/slub: remove meaningless node check in ___slab_alloc() mm/slub: remove duplicate flag in allocate_slab() mm/slub: remove unused parameter in setup_object*() mm/slab.c: fix comments slab, documentation: add description of debugfs files for SLUB caches mm/slub: sort debugfs output by frequency of stack traces mm/slub: distinguish and print stack traces in debugfs files mm/slub: use stackdepot to save stack trace in objects mm/slub: move struct track init out of set_track() lib/stackdepot: allow requesting early initialization dynamically mm/slub, kunit: Make slub_kunit unaffected by user specified flags mm/slab: remove some unused functions

Documentation/vm: rework "Temporary Virtual Mappings" section

2022-05-13T23:48:55Z

Extend and rework the "Temporary Virtual Mappings" section of the highmem.rst documentation. Despite the local kmaps were introduced by Thomas Gleixner in October 2020, documentation was still missing information about them. These additions rely largely on Gleixner's patches, Jonathan Corbet's LWN articles, comments by Ira Weiny and Matthew Wilcox, and in-code comments from ./include/linux/highmem.h. 1) Add a paragraph to document kmap_local_page(). 2) Reorder the list of functions by decreasing order of preference of use. 3) Rework part of the kmap() entry in list. Link: https://lkml.kernel.org/r/20220428212455.892-5-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco Suggested-by: Ira Weiny Reviewed-by: Sebastian Andrzej Siewior Reviewed-by: Ira Weiny Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Catalin Marinas Cc: Mike Rapoport Cc: Peter Collingbourne Cc: Vlastimil Babka Cc: Will Deacon Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Documentation/vm: move "Using kmap-atomic" to highmem.h

2022-05-13T23:48:55Z

The use of kmap_atomic() is new code is being deprecated in favor of kmap_local_page(). For this reason the "Using kmap_atomic" section in highmem.rst is obsolete and unnecessary, but it can still help developers if it were moved to kdocs in highmem.h. Therefore, move the relevant parts of this section from highmem.rst and merge them with the kdocs in highmem.h. Link: https://lkml.kernel.org/r/20220428212455.892-4-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco Suggested-by: Ira Weiny Reviewed-by: Sebastian Andrzej Siewior Reviewed-by: Ira Weiny Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Catalin Marinas Cc: Mike Rapoport Cc: Peter Collingbourne Cc: Vlastimil Babka Cc: Will Deacon Cc: Jonathan Corbet Signed-off-by: Andrew Morton

Documentation/vm: include kdocs from highmem*.h into highmem.rst

2022-05-13T23:48:55Z

kernel-docs that are in include/linux/highmem.h and in include/linux/highmem-internal.h should be included in highmem.rst. Use kdocs directives to include the above-mentioned comments into highmem.rst. Link: https://lkml.kernel.org/r/20220428212455.892-3-fmdefrancesco@gmail.com Signed-off-by: Fabio M. De Francesco Acked-by: Mike Rapoport Reviewed-by: Ira Weiny Suggested-by: Ira Weiny Reviewed-by: Sebastian Andrzej Siewior Cc: Jonathan Corbet Cc: Matthew Wilcox Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Catalin Marinas Cc: Peter Collingbourne Cc: Vlastimil Babka Cc: Will Deacon Cc: Jonathan Corbet Signed-off-by: Andrew Morton

docs: vm/page_owner: tweak literal block in STANDARD FORMAT SPECIFIERS

2022-05-13T14:20:18Z

A semantic conflict between commit 5603f9bdea68 ("docs: vm/page_owner: use literal blocks for param description") and a change queued for v5.19 authored by Jiajian Ye ("tools/vm/page_owner_sort.c: support sorting blocks by multiple keys") results in a warning from "make htmldocs" saying: [...]/vm/page_owner.rst:176: WARNING: Literal block expected; none found. This is because a literal block in ReST ends at a line which has the same indent as the paragraph preceding it. In this case the one with no indent. Indent the two "For --xxxx option:" lines by two columns and make the whole section a literal block. While at it, fix indents by white spaces of "ator" keys. Link: https://lkml.kernel.org/r/fdfecc82-d41e-6d8a-738d-4beb6faa27fb@gmail.com Signed-of-by: Akira Yokosawa Reported-by: Shenghong Han Cc: Jiajian Ye Cc: Chongxi Zhao Cc: Yinan Zhang Cc: Yixuan Cao Cc: Yongqiang Liu Cc: Yuhong Feng Cc: Haowen Bai Cc: Jonathan Corbet Signed-off-by: Andrew Morton

mm,doc: Add new documentation structure

2022-05-09T22:41:24Z

Closely following the outline of Mel Gorman's book "Understanding the Linux Virtual Memory Manager", add a new outline. Preserve the current contents of the mm underneath the new outline so we can transition those documents to a more sensible place later. Signed-off-by: Matthew Wilcox (Oracle) Reviewed-by: John Hubbard Acked-by: Randy Dunlap Acked-by: Johannes Weiner Link: https://lore.kernel.org/r/20220507134947.444287-1-willy@infradead.org Signed-off-by: Jonathan Corbet