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2024-03-15Merge tag 'mm-stable-2024-03-13-20-04' of ↵Linus Torvalds1-4/+4
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Sumanth Korikkar has taught s390 to allocate hotplug-time page frames from hotplugged memory rather than only from main memory. Series "implement "memmap on memory" feature on s390". - More folio conversions from Matthew Wilcox in the series "Convert memcontrol charge moving to use folios" "mm: convert mm counter to take a folio" - Chengming Zhou has optimized zswap's rbtree locking, providing significant reductions in system time and modest but measurable reductions in overall runtimes. The series is "mm/zswap: optimize the scalability of zswap rb-tree". - Chengming Zhou has also provided the series "mm/zswap: optimize zswap lru list" which provides measurable runtime benefits in some swap-intensive situations. - And Chengming Zhou further optimizes zswap in the series "mm/zswap: optimize for dynamic zswap_pools". Measured improvements are modest. - zswap cleanups and simplifications from Yosry Ahmed in the series "mm: zswap: simplify zswap_swapoff()". - In the series "Add DAX ABI for memmap_on_memory", Vishal Verma has contributed several DAX cleanups as well as adding a sysfs tunable to control the memmap_on_memory setting when the dax device is hotplugged as system memory. - Johannes Weiner has added the large series "mm: zswap: cleanups", which does that. - More DAMON work from SeongJae Park in the series "mm/damon: make DAMON debugfs interface deprecation unignorable" "selftests/damon: add more tests for core functionalities and corner cases" "Docs/mm/damon: misc readability improvements" "mm/damon: let DAMOS feeds and tame/auto-tune itself" - In the series "mm/mempolicy: weighted interleave mempolicy and sysfs extension" Rakie Kim has developed a new mempolicy interleaving policy wherein we allocate memory across nodes in a weighted fashion rather than uniformly. This is beneficial in heterogeneous memory environments appearing with CXL. - Christophe Leroy has contributed some cleanup and consolidation work against the ARM pagetable dumping code in the series "mm: ptdump: Refactor CONFIG_DEBUG_WX and check_wx_pages debugfs attribute". - Luis Chamberlain has added some additional xarray selftesting in the series "test_xarray: advanced API multi-index tests". - Muhammad Usama Anjum has reworked the selftest code to make its human-readable output conform to the TAP ("Test Anything Protocol") format. Amongst other things, this opens up the use of third-party tools to parse and process out selftesting results. - Ryan Roberts has added fork()-time PTE batching of THP ptes in the series "mm/memory: optimize fork() with PTE-mapped THP". Mainly targeted at arm64, this significantly speeds up fork() when the process has a large number of pte-mapped folios. - David Hildenbrand also gets in on the THP pte batching game in his series "mm/memory: optimize unmap/zap with PTE-mapped THP". It implements batching during munmap() and other pte teardown situations. The microbenchmark improvements are nice. - And in the series "Transparent Contiguous PTEs for User Mappings" Ryan Roberts further utilizes arm's pte's contiguous bit ("contpte mappings"). Kernel build times on arm64 improved nicely. Ryan's series "Address some contpte nits" provides some followup work. - In the series "mm/hugetlb: Restore the reservation" Breno Leitao has fixed an obscure hugetlb race which was causing unnecessary page faults. He has also added a reproducer under the selftest code. - In the series "selftests/mm: Output cleanups for the compaction test", Mark Brown did what the title claims. - Kinsey Ho has added the series "mm/mglru: code cleanup and refactoring". - Even more zswap material from Nhat Pham. The series "fix and extend zswap kselftests" does as claimed. - In the series "Introduce cpu_dcache_is_aliasing() to fix DAX regression" Mathieu Desnoyers has cleaned up and fixed rather a mess in our handling of DAX on archiecctures which have virtually aliasing data caches. The arm architecture is the main beneficiary. - Lokesh Gidra's series "per-vma locks in userfaultfd" provides dramatic improvements in worst-case mmap_lock hold times during certain userfaultfd operations. - Some page_owner enhancements and maintenance work from Oscar Salvador in his series "page_owner: print stacks and their outstanding allocations" "page_owner: Fixup and cleanup" - Uladzislau Rezki has contributed some vmalloc scalability improvements in his series "Mitigate a vmap lock contention". It realizes a 12x improvement for a certain microbenchmark. - Some kexec/crash cleanup work from Baoquan He in the series "Split crash out from kexec and clean up related config items". - Some zsmalloc maintenance work from Chengming Zhou in the series "mm/zsmalloc: fix and optimize objects/page migration" "mm/zsmalloc: some cleanup for get/set_zspage_mapping()" - Zi Yan has taught the MM to perform compaction on folios larger than order=0. This a step along the path to implementaton of the merging of large anonymous folios. The series is named "Enable >0 order folio memory compaction". - Christoph Hellwig has done quite a lot of cleanup work in the pagecache writeback code in his series "convert write_cache_pages() to an iterator". - Some modest hugetlb cleanups and speedups in Vishal Moola's series "Handle hugetlb faults under the VMA lock". - Zi Yan has changed the page splitting code so we can split huge pages into sizes other than order-0 to better utilize large folios. The series is named "Split a folio to any lower order folios". - David Hildenbrand has contributed the series "mm: remove total_mapcount()", a cleanup. - Matthew Wilcox has sought to improve the performance of bulk memory freeing in his series "Rearrange batched folio freeing". - Gang Li's series "hugetlb: parallelize hugetlb page init on boot" provides large improvements in bootup times on large machines which are configured to use large numbers of hugetlb pages. - Matthew Wilcox's series "PageFlags cleanups" does that. - Qi Zheng's series "minor fixes and supplement for ptdesc" does that also. S390 is affected. - Cleanups to our pagemap utility functions from Peter Xu in his series "mm/treewide: Replace pXd_large() with pXd_leaf()". - Nico Pache has fixed a few things with our hugepage selftests in his series "selftests/mm: Improve Hugepage Test Handling in MM Selftests". - Also, of course, many singleton patches to many things. Please see the individual changelogs for details. * tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (435 commits) mm/zswap: remove the memcpy if acomp is not sleepable crypto: introduce: acomp_is_async to expose if comp drivers might sleep memtest: use {READ,WRITE}_ONCE in memory scanning mm: prohibit the last subpage from reusing the entire large folio mm: recover pud_leaf() definitions in nopmd case selftests/mm: skip the hugetlb-madvise tests on unmet hugepage requirements selftests/mm: skip uffd hugetlb tests with insufficient hugepages selftests/mm: dont fail testsuite due to a lack of hugepages mm/huge_memory: skip invalid debugfs new_order input for folio split mm/huge_memory: check new folio order when split a folio mm, vmscan: retry kswapd's priority loop with cache_trim_mode off on failure mm: add an explicit smp_wmb() to UFFDIO_CONTINUE mm: fix list corruption in put_pages_list mm: remove folio from deferred split list before uncharging it filemap: avoid unnecessary major faults in filemap_fault() mm,page_owner: drop unnecessary check mm,page_owner: check for null stack_record before bumping its refcount mm: swap: fix race between free_swap_and_cache() and swapoff() mm/treewide: align up pXd_leaf() retval across archs mm/treewide: drop pXd_large() ...
2024-02-24mm/vmalloc: remove vmap_area_listBaoquan He1-4/+4
Earlier, vmap_area_list is exported to vmcoreinfo so that makedumpfile get the base address of vmalloc area. Now, vmap_area_list is empty, so export VMALLOC_START to vmcoreinfo instead, and remove vmap_area_list. [urezki@gmail.com: fix a warning in the crash_save_vmcoreinfo_init()] Link: https://lkml.kernel.org/r/20240111192329.449189-1-urezki@gmail.com Link: https://lkml.kernel.org/r/20240102184633.748113-6-urezki@gmail.com Signed-off-by: Baoquan He <bhe@redhat.com> Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com> Acked-by: Lorenzo Stoakes <lstoakes@gmail.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Dave Chinner <david@fromorbit.com> Cc: Joel Fernandes (Google) <joel@joelfernandes.org> Cc: Kazuhito Hagio <k-hagio-ab@nec.com> Cc: Liam R. Howlett <Liam.Howlett@oracle.com> Cc: Matthew Wilcox (Oracle) <willy@infradead.org> Cc: Oleksiy Avramchenko <oleksiy.avramchenko@sony.com> Cc: Paul E. McKenney <paulmck@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-02-16x86/cpu: Detect real BSP on crash kernelsThomas Gleixner1-5/+2
When a kdump kernel is started from a crashing CPU then there is no guarantee that this CPU is the real boot CPU (BSP). If the kdump kernel tries to online the BSP then the INIT sequence will reset the machine. There is a command line option to prevent this, but in case of nested kdump kernels this is wrong. But that command line option is not required at all because the real BSP is enumerated as the first CPU by firmware. Support for the only known system which was different (Voyager) got removed long ago. Detect whether the boot CPU APIC ID is the first APIC ID enumerated by the firmware. If the first APIC ID enumerated is not matching the boot CPU APIC ID then skip registering it. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Michael Kelley <mhklinux@outlook.com> Tested-by: Sohil Mehta <sohil.mehta@intel.com> Link: https://lore.kernel.org/r/20240213210252.348542071@linutronix.de
2024-01-09mm, treewide: rename MAX_ORDER to MAX_PAGE_ORDERKirill A. Shutemov1-1/+1
commit 23baf831a32c ("mm, treewide: redefine MAX_ORDER sanely") has changed the definition of MAX_ORDER to be inclusive. This has caused issues with code that was not yet upstream and depended on the previous definition. To draw attention to the altered meaning of the define, rename MAX_ORDER to MAX_PAGE_ORDER. Link: https://lkml.kernel.org/r/20231228144704.14033-2-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-01-09mm, treewide: introduce NR_PAGE_ORDERSKirill A. Shutemov1-3/+3
NR_PAGE_ORDERS defines the number of page orders supported by the page allocator, ranging from 0 to MAX_ORDER, MAX_ORDER + 1 in total. NR_PAGE_ORDERS assists in defining arrays of page orders and allows for more natural iteration over them. [kirill.shutemov@linux.intel.com: fixup for kerneldoc warning] Link: https://lkml.kernel.org/r/20240101111512.7empzyifq7kxtzk3@box Link: https://lkml.kernel.org/r/20231228144704.14033-1-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Zi Yan <ziy@nvidia.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-09-11Documentation: Drop or replace remaining mentions of IA64Ard Biesheuvel2-64/+3
Drop or update mentions of IA64, as appropriate. Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
2023-08-30Merge tag 'mm-stable-2023-08-28-18-26' of ↵Linus Torvalds1-10/+4
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - Some swap cleanups from Ma Wupeng ("fix WARN_ON in add_to_avail_list") - Peter Xu has a series (mm/gup: Unify hugetlb, speed up thp") which reduces the special-case code for handling hugetlb pages in GUP. It also speeds up GUP handling of transparent hugepages. - Peng Zhang provides some maple tree speedups ("Optimize the fast path of mas_store()"). - Sergey Senozhatsky has improved te performance of zsmalloc during compaction (zsmalloc: small compaction improvements"). - Domenico Cerasuolo has developed additional selftest code for zswap ("selftests: cgroup: add zswap test program"). - xu xin has doe some work on KSM's handling of zero pages. These changes are mainly to enable the user to better understand the effectiveness of KSM's treatment of zero pages ("ksm: support tracking KSM-placed zero-pages"). - Jeff Xu has fixes the behaviour of memfd's MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED sysctl ("mm/memfd: fix sysctl MEMFD_NOEXEC_SCOPE_NOEXEC_ENFORCED"). - David Howells has fixed an fscache optimization ("mm, netfs, fscache: Stop read optimisation when folio removed from pagecache"). - Axel Rasmussen has given userfaultfd the ability to simulate memory poisoning ("add UFFDIO_POISON to simulate memory poisoning with UFFD"). - Miaohe Lin has contributed some routine maintenance work on the memory-failure code ("mm: memory-failure: remove unneeded PageHuge() check"). - Peng Zhang has contributed some maintenance work on the maple tree code ("Improve the validation for maple tree and some cleanup"). - Hugh Dickins has optimized the collapsing of shmem or file pages into THPs ("mm: free retracted page table by RCU"). - Jiaqi Yan has a patch series which permits us to use the healthy subpages within a hardware poisoned huge page for general purposes ("Improve hugetlbfs read on HWPOISON hugepages"). - Kemeng Shi has done some maintenance work on the pagetable-check code ("Remove unused parameters in page_table_check"). - More folioification work from Matthew Wilcox ("More filesystem folio conversions for 6.6"), ("Followup folio conversions for zswap"). And from ZhangPeng ("Convert several functions in page_io.c to use a folio"). - page_ext cleanups from Kemeng Shi ("minor cleanups for page_ext"). - Baoquan He has converted some architectures to use the GENERIC_IOREMAP ioremap()/iounmap() code ("mm: ioremap: Convert architectures to take GENERIC_IOREMAP way"). - Anshuman Khandual has optimized arm64 tlb shootdown ("arm64: support batched/deferred tlb shootdown during page reclamation/migration"). - Better maple tree lockdep checking from Liam Howlett ("More strict maple tree lockdep"). Liam also developed some efficiency improvements ("Reduce preallocations for maple tree"). - Cleanup and optimization to the secondary IOMMU TLB invalidation, from Alistair Popple ("Invalidate secondary IOMMU TLB on permission upgrade"). - Ryan Roberts fixes some arm64 MM selftest issues ("selftests/mm fixes for arm64"). - Kemeng Shi provides some maintenance work on the compaction code ("Two minor cleanups for compaction"). - Some reduction in mmap_lock pressure from Matthew Wilcox ("Handle most file-backed faults under the VMA lock"). - Aneesh Kumar contributes code to use the vmemmap optimization for DAX on ppc64, under some circumstances ("Add support for DAX vmemmap optimization for ppc64"). - page-ext cleanups from Kemeng Shi ("add page_ext_data to get client data in page_ext"), ("minor cleanups to page_ext header"). - Some zswap cleanups from Johannes Weiner ("mm: zswap: three cleanups"). - kmsan cleanups from ZhangPeng ("minor cleanups for kmsan"). - VMA handling cleanups from Kefeng Wang ("mm: convert to vma_is_initial_heap/stack()"). - DAMON feature work from SeongJae Park ("mm/damon/sysfs-schemes: implement DAMOS tried total bytes file"), ("Extend DAMOS filters for address ranges and DAMON monitoring targets"). - Compaction work from Kemeng Shi ("Fixes and cleanups to compaction"). - Liam Howlett has improved the maple tree node replacement code ("maple_tree: Change replacement strategy"). - ZhangPeng has a general code cleanup - use the K() macro more widely ("cleanup with helper macro K()"). - Aneesh Kumar brings memmap-on-memory to ppc64 ("Add support for memmap on memory feature on ppc64"). - pagealloc cleanups from Kemeng Shi ("Two minor cleanups for pcp list in page_alloc"), ("Two minor cleanups for get pageblock migratetype"). - Vishal Moola introduces a memory descriptor for page table tracking, "struct ptdesc" ("Split ptdesc from struct page"). - memfd selftest maintenance work from Aleksa Sarai ("memfd: cleanups for vm.memfd_noexec"). - MM include file rationalization from Hugh Dickins ("arch: include asm/cacheflush.h in asm/hugetlb.h"). - THP debug output fixes from Hugh Dickins ("mm,thp: fix sloppy text output"). - kmemleak improvements from Xiaolei Wang ("mm/kmemleak: use object_cache instead of kmemleak_initialized"). - More folio-related cleanups from Matthew Wilcox ("Remove _folio_dtor and _folio_order"). - A VMA locking scalability improvement from Suren Baghdasaryan ("Per-VMA lock support for swap and userfaults"). - pagetable handling cleanups from Matthew Wilcox ("New page table range API"). - A batch of swap/thp cleanups from David Hildenbrand ("mm/swap: stop using page->private on tail pages for THP_SWAP + cleanups"). - Cleanups and speedups to the hugetlb fault handling from Matthew Wilcox ("Change calling convention for ->huge_fault"). - Matthew Wilcox has also done some maintenance work on the MM subsystem documentation ("Improve mm documentation"). * tag 'mm-stable-2023-08-28-18-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (489 commits) maple_tree: shrink struct maple_tree maple_tree: clean up mas_wr_append() secretmem: convert page_is_secretmem() to folio_is_secretmem() nios2: fix flush_dcache_page() for usage from irq context hugetlb: add documentation for vma_kernel_pagesize() mm: add orphaned kernel-doc to the rst files. mm: fix clean_record_shared_mapping_range kernel-doc mm: fix get_mctgt_type() kernel-doc mm: fix kernel-doc warning from tlb_flush_rmaps() mm: remove enum page_entry_size mm: allow ->huge_fault() to be called without the mmap_lock held mm: move PMD_ORDER to pgtable.h mm: remove checks for pte_index memcg: remove duplication detection for mem_cgroup_uncharge_swap mm/huge_memory: work on folio->swap instead of page->private when splitting folio mm/swap: inline folio_set_swap_entry() and folio_swap_entry() mm/swap: use dedicated entry for swap in folio mm/swap: stop using page->private on tail pages for THP_SWAP selftests/mm: fix WARNING comparing pointer to 0 selftests: cgroup: fix test_kmem_memcg_deletion kernel mem check ...
2023-08-22mm: add large_rmappable page flagMatthew Wilcox (Oracle)1-2/+2
Stored in the first tail page's flags, this flag replaces the destructor. That removes the last of the destructors, so remove all references to folio_dtor and compound_dtor. Link: https://lkml.kernel.org/r/20230816151201.3655946-9-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>
2023-08-22mm: remove HUGETLB_PAGE_DTORMatthew Wilcox (Oracle)1-8/+2
We can use a bit in page[1].flags to indicate that this folio belongs to hugetlb instead of using a value in page[1].dtors. That lets folio_test_hugetlb() become an inline function like it should be. We can also get rid of NULL_COMPOUND_DTOR. Link: https://lkml.kernel.org/r/20230816151201.3655946-8-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>
2023-08-02Documentation: kdump: Add va_kernel_pa_offset for RISCV64Song Shuai1-0/+6
RISC-V Linux exports "va_kernel_pa_offset" in vmcoreinfo to help Crash-utility translate the kernel virtual address correctly. Here adds the definition of "va_kernel_pa_offset". Fixes: 3335068f8721 ("riscv: Use PUD/P4D/PGD pages for the linear mapping") Link: https://lore.kernel.org/linux-riscv/20230724040649.220279-1-suagrfillet@gmail.com/ Signed-off-by: Song Shuai <suagrfillet@gmail.com> Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com> Link: https://lore.kernel.org/r/20230724100917.309061-2-suagrfillet@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2023-04-06mm, treewide: redefine MAX_ORDER sanelyKirill A. Shutemov1-3/+3
MAX_ORDER currently defined as number of orders page allocator supports: user can ask buddy allocator for page order between 0 and MAX_ORDER-1. This definition is counter-intuitive and lead to number of bugs all over the kernel. Change the definition of MAX_ORDER to be inclusive: the range of orders user can ask from buddy allocator is 0..MAX_ORDER now. [kirill@shutemov.name: fix min() warning] Link: https://lkml.kernel.org/r/20230315153800.32wib3n5rickolvh@box [akpm@linux-foundation.org: fix another min_t warning] [kirill@shutemov.name: fixups per Zi Yan] Link: https://lkml.kernel.org/r/20230316232144.b7ic4cif4kjiabws@box.shutemov.name [akpm@linux-foundation.org: fix underlining in docs] Link: https://lore.kernel.org/oe-kbuild-all/202303191025.VRCTk6mP-lkp@intel.com/ Link: https://lkml.kernel.org/r/20230315113133.11326-11-kirill.shutemov@linux.intel.com Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Reviewed-by: Michael Ellerman <mpe@ellerman.id.au> [powerpc] Cc: "Kirill A. Shutemov" <kirill@shutemov.name> Cc: Zi Yan <ziy@nvidia.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-02-24Merge tag 'printk-for-6.3' of ↵Linus Torvalds1-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: - Refactor printk code for formatting messages that are shown on consoles. This is a preparatory step for introducing atomic consoles which could not share the global buffers - Prevent memory leak when removing printk index in debugfs - Dump also the newest printk message by the sample gdbmacro - Fix a compiler warning * tag 'printk-for-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: printf: fix errname.c list kernel/printk/index.c: fix memory leak with using debugfs_lookup() printk: Use scnprintf() to print the message about the dropped messages on a console printk: adjust string limit macros printk: use printk_buffers for devkmsg printk: introduce console_prepend_dropped() for dropped messages printk: introduce printk_get_next_message() and printk_message printk: introduce struct printk_buffers console: Document struct console console: Use BIT() macros for @flags values printk: move size limit macros into internal.h docs: gdbmacros: print newest record
2023-01-03docs: gdbmacros: print newest recordJohn Ogness1-1/+1
@head_id points to the newest record, but the printing loop exits when it increments to this value (before printing). Exit the printing loop after the newest record has been printed. The python-based function in scripts/gdb/linux/dmesg.py already does this correctly. Fixes: e60768311af8 ("scripts/gdb: update for lockless printk ringbuffer") Cc: stable@vger.kernel.org Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20221229134339.197627-1-john.ogness@linutronix.de
2022-12-03Documentation: kdump: describe VMCOREINFO export for RISCV64Xianting Tian1-0/+29
The following interrelated definitions and ranges are needed by the kdump crash tool, which are exported by "arch/riscv/kernel/crash_core.c": VA_BITS, PAGE_OFFSET, phys_ram_base, KERNEL_LINK_ADDR, MODULES_VADDR ~ MODULES_END, VMALLOC_START ~ VMALLOC_END, VMEMMAP_START ~ VMEMMAP_END, Document these RISCV64 exports above. Reviewed-by: Bagas Sanjaya <bagasdotme@gmail.com> Signed-off-by: Xianting Tian <xianting.tian@linux.alibaba.com> Acked-by: Baoquan He <bhe@redhat.com> Link: https://lore.kernel.org/r/20221026144208.373504-3-xianting.tian@linux.alibaba.com [Palmer: wrap commit text] Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
2022-09-27Remove duplicate words inside documentationAkhil Raj1-1/+1
I have removed repeated `the` inside the documentation Signed-off-by: Akhil Raj <lf32.dev@gmail.com> Link: https://lore.kernel.org/r/20220827145359.32599-1-lf32.dev@gmail.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2022-03-25Merge branch 'akpm' (patches from Andrew)Linus Torvalds1-3/+7
Merge more updates from Andrew Morton: "Various misc subsystems, before getting into the post-linux-next material. 41 patches. Subsystems affected by this patch series: procfs, misc, core-kernel, lib, checkpatch, init, pipe, minix, fat, cgroups, kexec, kdump, taskstats, panic, kcov, resource, and ubsan" * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (41 commits) Revert "ubsan, kcsan: Don't combine sanitizer with kcov on clang" kernel/resource: fix kfree() of bootmem memory again kcov: properly handle subsequent mmap calls kcov: split ioctl handling into locked and unlocked parts panic: move panic_print before kmsg dumpers panic: add option to dump all CPUs backtraces in panic_print docs: sysctl/kernel: add missing bit to panic_print taskstats: remove unneeded dead assignment kasan: no need to unset panic_on_warn in end_report() ubsan: no need to unset panic_on_warn in ubsan_epilogue() panic: unset panic_on_warn inside panic() docs: kdump: add scp example to write out the dump file docs: kdump: update description about sysfs file system support arm64: mm: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef x86/setup: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef riscv: mm: init: use IS_ENABLED(CONFIG_KEXEC_CORE) instead of #ifdef kexec: make crashk_res, crashk_low_res and crash_notes symbols always visible cgroup: use irqsave in cgroup_rstat_flush_locked(). fat: use pointer to simple type in put_user() minix: fix bug when opening a file with O_DIRECT ...
2022-03-24docs: kdump: add scp example to write out the dump fileTiezhu Yang1-0/+4
Except cp and makedumpfile, add scp example to write out the dump file. Link: https://lkml.kernel.org/r/1644324666-15947-3-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Baoquan He <bhe@redhat.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Marco Elver <elver@google.com> Cc: Xuefeng Li <lixuefeng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24docs: kdump: update description about sysfs file system supportTiezhu Yang1-3/+3
Patch series "Update doc and fix some issues about kdump", v2. This patch (of 5): After commit 6a108a14fa35 ("kconfig: rename CONFIG_EMBEDDED to CONFIG_EXPERT"), "Configure standard kernel features (for small systems)" is not exist, we should use "Configure standard kernel features (expert users)" now. Link: https://lkml.kernel.org/r/1644324666-15947-1-git-send-email-yangtiezhu@loongson.cn Link: https://lkml.kernel.org/r/1644324666-15947-2-git-send-email-yangtiezhu@loongson.cn Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Acked-by: Baoquan He <bhe@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Marco Elver <elver@google.com> Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com> Cc: Xuefeng Li <lixuefeng@loongson.cn> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-09Documentation: vmcoreinfo: Fix htmldocs warningWill Deacon1-1/+1
Since commit 2369f171d5c5 ("arm64: crash_core: Export MODULES, VMALLOC, and VMEMMAP ranges"), Stephen reports a warning when building htmldocs: | Documentation/admin-guide/kdump/vmcoreinfo.rst:498: WARNING: Title underline too short. Extend the underline to squash the warning. Fixes: 2369f171d5c5 ("arm64: crash_core: Export MODULES, VMALLOC, and VMEMMAP ranges") Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Will Deacon <will@kernel.org>
2022-03-08arm64: crash_core: Export MODULES, VMALLOC, and VMEMMAP rangesHuang Shijie1-0/+8
The following interrelated ranges are needed by the kdump crash tool: MODULES_VADDR ~ MODULES_END, VMALLOC_START ~ VMALLOC_END, VMEMMAP_START ~ VMEMMAP_END Since these values change from time to time, it is preferable to export them via vmcoreinfo than to change the crash's code frequently. Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com> Link: https://lore.kernel.org/r/20220209092642.9181-1-shijie@os.amperecomputing.com Signed-off-by: Will Deacon <will@kernel.org>
2021-06-14Documentation: kdump: update kdump guideBaoquan He1-61/+109
Some parts of the guide are aged, hence need be updated. 1) The backup area of the 1st 640K on X86_64 has been removed by below commits, update the description accordingly. commit 7c321eb2b843 ("x86/kdump: Remove the backup region handling") commit 6f599d84231f ("x86/kdump: Always reserve the low 1M when the crashkernel option is specified") 2) Sort out the descripiton of "crashkernel syntax" part. 3) And some other minor cleanups. Signed-off-by: Baoquan He <bhe@redhat.com> Acked-by: Dave Young <dyoung@redhat.com> Link: https://lore.kernel.org/r/20210609083218.GB591017@MiWiFi-R3L-srv [jc: added blank line to fix added build warning] Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-12-16kdump: append uts_namespace.name offset to VMCOREINFOAlexander Egorenkov1-0/+6
The offset of the field 'init_uts_ns.name' has changed since commit 9a56493f6942 ("uts: Use generic ns_common::count"). Make the offset of the field 'uts_namespace.name' available in VMCOREINFO because tools like 'crash-utility' and 'makedumpfile' must be able to read it from crash dumps. Link: https://lore.kernel.org/r/159644978167.604812.1773586504374412107.stgit@localhost.localdomain Link: https://lkml.kernel.org/r/20200930102328.396488-1-egorenar@linux.ibm.com Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com> Acked-by: lijiang <lijiang@redhat.com> Acked-by: Baoquan He <bhe@redhat.com> Cc: Dave Young <dyoung@redhat.com> Cc: Vivek Goyal <vgoyal@redhat.com> Cc: "Eric W . Biederman" <ebiederm@xmission.com> Cc: Kirill Tkhai <ktkhai@virtuozzo.com> Cc: Kees Cook <keescook@chromium.org> Cc: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-14Merge tag 'printk-for-5.10' of ↵Linus Torvalds2-79/+211
git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux Pull printk updates from Petr Mladek: "The big new thing is the fully lockless ringbuffer implementation, including the support for continuous lines. It will allow to store and read messages in any situation wihtout the risk of deadlocks and without the need of temporary per-CPU buffers. The access is still serialized by logbuf_lock. It synchronizes few more operations, for example, temporary buffer for formatting the message, syslog and kmsg_dump operations. The lock removal is being discussed and should be ready for the next release. The continuous lines are handled exactly the same way as before to avoid regressions in user space. It means that they are appended to the last message when the caller is the same. Only the last message can be extended. The data ring includes plain text of the messages. Except for an integer at the beginning of each message that points back to the descriptor ring with other metadata. The dictionary has to stay. journalctl uses it to filter the log. It allows to show messages related to a given device. The dictionary values are stored in the descriptor ring with the other metadata. This is the first part of the printk rework as discussed at Plumbers 2019, see https://lore.kernel.org/r/87k1acz5rx.fsf@linutronix.de. The next big step will be handling consoles by kthreads during the normal system operation. It will require special handling of situations when the kthreads could not get scheduled, for example, early boot, suspend, panic. Other changes: - Add John Ogness as a reviewer for printk subsystem. He is author of the rework and is familiar with the code and history. - Fix locking in serial8250_do_startup() to prevent lockdep report. - Few code cleanups" * tag 'printk-for-5.10' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux: (27 commits) printk: Use fallthrough pseudo-keyword printk: reduce setup_text_buf size to LOG_LINE_MAX printk: avoid and/or handle record truncation printk: remove dict ring printk: move dictionary keys to dev_printk_info printk: move printk_info into separate array printk: reimplement log_cont using record extension printk: ringbuffer: add finalization/extension support printk: ringbuffer: change representation of states printk: ringbuffer: clear initial reserved fields printk: ringbuffer: add BLK_DATALESS() macro printk: ringbuffer: relocate get_data() printk: ringbuffer: avoid memcpy() on state_var printk: ringbuffer: fix setting state in desc_read() kernel.h: Move oops_in_progress to printk.h scripts/gdb: update for lockless printk ringbuffer scripts/gdb: add utils.read_ulong() docs: vmcoreinfo: add lockless printk ringbuffer vmcoreinfo printk: reduce LOG_BUF_SHIFT range for H8300 printk: ringbuffer: support dataless records ...
2020-10-12Merge branch 'printk-rework' into for-linusPetr Mladek2-79/+211
2020-09-24docs: admin-guide: update kdump documentation due to change of crash URLlijiang1-2/+5
Since crash utility has been moved to github, the original URL is no longer available. Let's update it accordingly. Suggested-by: Dave Young <dyoung@redhat.com> Signed-off-by: Lianbo Jiang <lijiang@redhat.com> Link: https://lore.kernel.org/r/a088bff5-1174-25fa-ac26-6e46795f4085@redhat.com Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2020-09-22printk: move dictionary keys to dev_printk_infoJohn Ogness1-40/+33
Dictionaries are only used for SUBSYSTEM and DEVICE properties. The current implementation stores the property names each time they are used. This requires more space than otherwise necessary. Also, because the dictionary entries are currently considered optional, it cannot be relied upon that they are always available, even if the writer wanted to store them. These issues will increase should new dictionary properties be introduced. Rather than storing the subsystem and device properties in the dict ring, introduce a struct dev_printk_info with separate fields to store only the property values. Embed this struct within the struct printk_info to provide guaranteed availability. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/87mu1jl6ne.fsf@jogness.linutronix.de
2020-09-15printk: ringbuffer: add finalization/extension supportJohn Ogness1-1/+2
Add support for extending the newest data block. For this, introduce a new finalization state (desc_finalized) denoting a committed descriptor that cannot be extended. Until a record is finalized, a writer can reopen that record to append new data. Reopening a record means transitioning from the desc_committed state back to the desc_reserved state. A writer can explicitly finalize a record if there is no intention of extending it. Also, records are automatically finalized when a new record is reserved. This relieves writers of needing to explicitly finalize while also making such records available to readers sooner. (Readers can only traverse finalized records.) Four new memory barrier pairs are introduced. Two of them are insignificant additions (data_realloc:A/desc_read:D and data_realloc:A/data_push_tail:B) because they are alternate path memory barriers that exactly match the purpose, pairing, and context of the two existing memory barrier pairs they provide an alternate path for. The other two new memory barrier pairs are significant additions: desc_reopen_last:A / _prb_commit:B - When reopening a descriptor, ensure the state transitions back to desc_reserved before fully trusting the descriptor data. _prb_commit:B / desc_reserve:D - When committing a descriptor, ensure the state transitions to desc_committed before checking the head ID to see if the descriptor needs to be finalized. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200914123354.832-6-john.ogness@linutronix.de
2020-09-15printk: ringbuffer: change representation of statesJohn Ogness1-4/+8
Rather than deriving the state by evaluating bits within the flags area of the state variable, assign the states explicit values and set those values in the flags area. Introduce macros to make it simple to read and write state values for the state variable. Although the functionality is preserved, the binary representation for the states is changed. Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200914123354.832-5-john.ogness@linutronix.de
2020-09-08scripts/gdb: update for lockless printk ringbufferJohn Ogness1-46/+107
With the introduction of the lockless printk ringbuffer, the data structure for the kernel log buffer was changed. Update the gdb scripts to be able to parse/print the new log buffer structure. Fixes: 896fbe20b4e2333fb55 ("printk: use the lockless ringbuffer") Signed-off-by: John Ogness <john.ogness@linutronix.de> Reported-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com> Tested-by: Petr Mladek <pmladek@suse.com> [akpm@linux-foundation.org: A typo fix.] Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200814212525.6118-3-john.ogness@linutronix.de
2020-09-08docs: vmcoreinfo: add lockless printk ringbuffer vmcoreinfoJohn Ogness1-29/+102
With the introduction of the lockless printk ringbuffer, the VMCOREINFO relating to the kernel log buffer was changed. Update the documentation to match those changes. Fixes: 896fbe20b4e2333fb55 ("printk: use the lockless ringbuffer") Reported-by: Nick Desaulniers <ndesaulniers@google.com> Signed-off-by: John Ogness <john.ogness@linutronix.de> Reviewed-by: Petr Mladek <pmladek@suse.com> Signed-off-by: Petr Mladek <pmladek@suse.com> Link: https://lore.kernel.org/r/20200814213316.6394-1-john.ogness@linutronix.de
2020-07-02arm64/crash_core: Export TCR_EL1.T1SZ in vmcoreinfoBhupesh Sharma1-0/+11
TCR_EL1.TxSZ, which controls the VA space size, is configured by a single kernel image to support either 48-bit or 52-bit VA space. If the ARMv8.2-LVA optional feature is present and we are running with a 64KB page size, then it is possible to use 52-bits of address space for both userspace and kernel addresses. However, any kernel binary that supports 52-bit must also be able to fall back to 48-bit at early boot time if the hardware feature is not present. Since TCR_EL1.T1SZ indicates the size of the memory region addressed by TTBR1_EL1, export the same in vmcoreinfo. User-space utilities like makedumpfile and crash-utility need to read this value from vmcoreinfo for determining if a virtual address lies in the linear map range. While at it also add documentation for TCR_EL1.T1SZ variable being added to vmcoreinfo. It indicates the size offset of the memory region addressed by TTBR1_EL1. Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com> Tested-by: John Donnelly <john.p.donnelly@oracle.com> Tested-by: Kamlakant Patel <kamlakantp@marvell.com> Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Steve Capper <steve.capper@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Dave Anderson <anderson@redhat.com> Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: kexec@lists.infradead.org Link: https://lore.kernel.org/r/1589395957-24628-3-git-send-email-bhsharma@redhat.com [catalin.marinas@arm.com: removed vabits_actual from the commit log] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-07-02crash_core, vmcoreinfo: Append 'MAX_PHYSMEM_BITS' to vmcoreinfoBhupesh Sharma1-0/+5
Right now user-space tools like 'makedumpfile' and 'crash' need to rely on a best-guess method of determining value of 'MAX_PHYSMEM_BITS' supported by underlying kernel. This value is used in user-space code to calculate the bit-space required to store a section for SPARESMEM (similar to the existing calculation method used in the kernel implementation): #define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS) Now, regressions have been reported in user-space utilities like 'makedumpfile' and 'crash' on arm64, with the recently added kernel support for 52-bit physical address space, as there is no clear method of determining this value in user-space (other than reading kernel CONFIG flags). As per suggestion from makedumpfile maintainer (Kazu), it makes more sense to append 'MAX_PHYSMEM_BITS' to vmcoreinfo in the core code itself rather than in arch-specific code, so that the user-space code for other archs can also benefit from this addition to the vmcoreinfo and use it as a standard way of determining 'SECTIONS_SHIFT' value in user-land. A reference 'makedumpfile' implementation which reads the 'MAX_PHYSMEM_BITS' value from vmcoreinfo in a arch-independent fashion is available here: While at it also update vmcoreinfo documentation for 'MAX_PHYSMEM_BITS' variable being added to vmcoreinfo. 'MAX_PHYSMEM_BITS' defines the maximum supported physical address space memory. Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com> Tested-by: John Donnelly <john.p.donnelly@oracle.com> Acked-by: Dave Young <dyoung@redhat.com> Cc: Boris Petkov <bp@alien8.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: James Morse <james.morse@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Dave Anderson <anderson@redhat.com> Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com> Cc: x86@kernel.org Cc: linuxppc-dev@lists.ozlabs.org Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Cc: kexec@lists.infradead.org Link: https://lore.kernel.org/r/1589395957-24628-2-git-send-email-bhsharma@redhat.com Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-06-08kernel: add panic_on_taintRafael Aquini1-0/+8
Analogously to the introduction of panic_on_warn, this patch introduces a kernel option named panic_on_taint in order to provide a simple and generic way to stop execution and catch a coredump when the kernel gets tainted by any given flag. This is useful for debugging sessions as it avoids having to rebuild the kernel to explicitly add calls to panic() into the code sites that introduce the taint flags of interest. For instance, if one is interested in proceeding with a post-mortem analysis at the point a given code path is hitting a bad page (i.e. unaccount_page_cache_page(), or slab_bug()), a coredump can be collected by rebooting the kernel with 'panic_on_taint=0x20' amended to the command line. Another, perhaps less frequent, use for this option would be as a means for assuring a security policy case where only a subset of taints, or no single taint (in paranoid mode), is allowed for the running system. The optional switch 'nousertaint' is handy in this particular scenario, as it will avoid userspace induced crashes by writes to sysctl interface /proc/sys/kernel/tainted causing false positive hits for such policies. [akpm@linux-foundation.org: tweak kernel-parameters.txt wording] Suggested-by: Qian Cai <cai@lca.pw> Signed-off-by: Rafael Aquini <aquini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Reviewed-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Kees Cook <keescook@chromium.org> Cc: Randy Dunlap <rdunlap@infradead.org> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Adrian Bunk <bunk@kernel.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Laura Abbott <labbott@redhat.com> Cc: Jeff Mahoney <jeffm@suse.com> Cc: Jiri Kosina <jikos@kernel.org> Cc: Takashi Iwai <tiwai@suse.de> Link: http://lkml.kernel.org/r/20200515175502.146720-1-aquini@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-11Documentation/vmcoreinfo: Add documentation for 'KERNELPACMASK'Amit Daniel Kachhap1-0/+6
Add documentation for KERNELPACMASK variable being added to the vmcoreinfo. It indicates the PAC bits mask information of signed kernel pointers if Armv8.3-A Pointer Authentication feature is present. Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Dave Young <dyoung@redhat.com> Cc: Baoquan He <bhe@redhat.com> Link: https://lore.kernel.org/r/1589202116-18265-2-git-send-email-amit.kachhap@arm.com Signed-off-by: Will Deacon <will@kernel.org>
2019-07-15docs: admin-guide: add kdump documentation into itMauro Carvalho Chehab4-0/+1306
The Kdump documentation describes procedures with admins use in order to solve issues on their systems. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>