user/sven/linux.git/lib/maple_tree.c, branch v6.9.3

maple_tree: fix mas_empty_area_rev() null pointer dereference

2024-05-06T00:28:05Z

Currently the code calls mas_start() followed by mas_data_end() if the maple state is MA_START, but mas_start() may return with the maple state node == NULL. This will lead to a null pointer dereference when checking information in the NULL node, which is done in mas_data_end(). Avoid setting the offset if there is no node by waiting until after the maple state is checked for an empty or single entry state. A user could trigger the events to cause a kernel oops by unmapping all vmas to produce an empty maple tree, then mapping a vma that would cause the scenario described above. Link: https://lkml.kernel.org/r/20240422203349.2418465-1-Liam.Howlett@oracle.com Fixes: 54a611b60590 ("Maple Tree: add new data structure") Signed-off-by: Liam R. Howlett Reported-by: Marius Fleischer Closes: https://lore.kernel.org/lkml/CAJg=8jyuSxDL6XvqEXY_66M20psRK2J53oBTP+fjV5xpW2-R6w@mail.gmail.com/ Link: https://lore.kernel.org/lkml/CAJg=8jyuSxDL6XvqEXY_66M20psRK2J53oBTP+fjV5xpW2-R6w@mail.gmail.com/ Tested-by: Marius Fleischer Tested-by: Sidhartha Kumar Cc: Signed-off-by: Andrew Morton

Merge tag 'mm-stable-2024-03-13-20-04' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2024-03-15T00:43:30Z

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() ...

maple_tree: avoid duplicate variable init in mast_spanning_rebalance()

2024-02-22T18:24:39Z

The local variables r_tmp and l_tmp in mast_spanning_rebalance() are already initialized at its declaration; there is no need to assign the value again. Remove the duplicate initialization of {r,l}_tmp. No functional change. Due to common compiler optimizations, also no change to object code. This issue was identified with clang-analyzer's dead stores analysis. Link: https://lkml.kernel.org/r/20240122102000.29558-1-lukas.bulwahn@gmail.com Signed-off-by: Lukas Bulwahn Reviewed-by: Liam R. Howlett Signed-off-by: Andrew Morton

maple_tree: fix comment describing mas_node_count_gfp()

2024-02-22T00:00:01Z

The function description comment for mas_node_count_gfp() mistakingly refers to the function as mas_node_count(). Change it to refer to the correct function. Link: https://lkml.kernel.org/r/20240109223119.162357-1-sidhartha.kumar@oracle.com Signed-off-by: Sidhartha Kumar Reviewed-by: Liam R. Howlett Cc: Peng Zhang Cc: Sidhartha Kumar Signed-off-by: Andrew Morton

maple_tree: Add mtree_alloc_cyclic()

2024-02-21T08:34:26Z

I need a cyclic allocator for the simple_offset implementation in fs/libfs.c. Signed-off-by: Chuck Lever Link: https://lore.kernel.org/r/170820144179.6328.12838600511394432325.stgit@91.116.238.104.host.secureserver.net Signed-off-by: Christian Brauner

maple_tree: avoid checking other gaps after getting the largest gap

2023-12-20T22:48:14Z

The last range stored in maple tree is typically quite large. By checking if it exceeds the sum of the remaining ranges in that node, it is possible to avoid checking all other gaps. Running the maple tree test suite in user mode almost always results in a near 100% hit rate for this optimization. Link: https://lkml.kernel.org/r/20231215074632.82045-1-zhangpeng.00@bytedance.com Signed-off-by: Peng Zhang Reviewed-by: Liam R. Howlett Signed-off-by: Andrew Morton

maple_tree: fix typos/spellos etc

2023-12-20T22:48:12Z

Fix typos/grammar and spellos in documentation. Link: https://lkml.kernel.org/r/20231210063839.29967-1-rdunlap@infradead.org Signed-off-by: Randy Dunlap Reviewed-by: Matthew Wilcox (Oracle) Cc: Liam R. Howlett Signed-off-by: Andrew Morton

lib/maple_tree.c: fix build error due to hotfix alteration

2023-12-20T22:48:11Z

Commit 0de56e38b307 ("maple_tree: use maple state end for write operations") was broken by a later patch "maple_tree: do not preallocate nodes for slot stores". But the later patch was scheduled ahead of 0de56e38b307, for 6.7-rc. This fixlet undoes the damage. Fixes: 0de56e38b307 ("maple_tree: use maple state end for write operations") Cc: Liam R. Howlett Cc: Sidhartha Kumar Signed-off-by: Andrew Morton

sync mm-stable with mm-hotfixes-stable to pick up depended-upon changes

2023-12-20T22:47:18Z

maple_tree: do not preallocate nodes for slot stores

2023-12-20T21:46:19Z

mas_preallocate() defaults to requesting 1 node for preallocation and then ,depending on the type of store, will update the request variable. There isn't a check for a slot store type, so slot stores are preallocating the default 1 node. Slot stores do not require any additional nodes, so add a check for the slot store case that will bypass node_count_gfp(). Update the tests to reflect that slot stores do not require allocations. User visible effects of this bug include increased memory usage from the unneeded node that was allocated. Link: https://lkml.kernel.org/r/20231213205058.386589-1-sidhartha.kumar@oracle.com Fixes: 0b8bb544b1a7 ("maple_tree: update mas_preallocate() testing") Signed-off-by: Sidhartha Kumar Cc: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Peng Zhang Cc: [6.6+] Signed-off-by: Andrew Morton