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2026-06-19Merge tag 'mm-stable-2026-06-18-09-26' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "selftests/mm: clean up build output and verbosity" (Li Wang) Remove some noise from the MM selftests build - "mm: Free contiguous order-0 pages efficiently" (Ryan Roberts) Speed up the freeing of a batch of 0-order pages by first scanning them for coalescing opportunities. This is applicable to vfree() and to the releasing of frozen pages - "mm/damon: introduce DAMOS failed region quota charge ratio" (SeongJae Park) Address a DAMOS usability issue: The DAMOS quota often exhausts prematurely because it charges for all memory attempted, causing slow and inconsistent performance when actions fail on unreclaimable memory. To fix this, a new feature lets users set a smaller, flexible quota charge ratio (via a numerator and denominator) for failed regions. Since failed actions cause less overhead, reducing their quota cost ensures more predictable and efficient DAMOS processing - "selftests/cgroup: improve zswap tests robustness and support large page sizes" (Li Wang) Fix various spurious failures and improves the overall robustness of the cgroup zswap selftests - "fix MAP_DROPPABLE not supported errno" (Anthony Yznaga) Fix an issue in the mlock selftests on arm32 - "mm: huge_memory: clean up defrag sysfs with shared" (Breno Leitao) Some maintenance work in the huge_memory code - "treewide: fixup gfp_t printks" (Brendan Jackman) Use the special vprintf() gfp_t conversion in various places - "mm: Fix vmemmap optimization accounting and initialization" (Muchun Song) Fix several bugs in the vmemmap optimization, mainly around incorrect page accounting and memmap initialization in the DAX and memory hotplug paths. It also fixes pageblock migratetype initialization and struct page initialization for ZONE_DEVICE compound pages - "mm/damon: repost non-hotfix reviewed patches in damon/next tree" A sprinkle of unrelated minor bugfixes for DAMON - "mm: remove page_mapped()" (David Hildenbrand) Remove this function from the tree, replacing it with folio_mapped() - "mm/damon: let DAMON be paused and resumed" (SeongJae Park) Allow DAMON to be paused and resumed without losing its current state - "kasan: hw_tags: Disable tagging for stack and page-tables" (Muhammad Usama Anjum) Simplify and speed up kasan by removing its ineffective tagging of stacks and page tables - "mm/damon/reclaim,lru_sort: monitor all system rams by default" (SeongJae Park) Simplify deployment on diverse hardware like NUMA systems by updating DAMON_RECLAIM and DAMON_LRU_SORT to automatically monitor the physical address range covering all System RAM areas by default, replacing the overly restrictive behavior that only targeted the single largest memory block to save on negligible overhead - "mm/damon/sysfs: document filters/ directory as deprecated" (SeongJae Park) Update some DAMON docs - "mm: use spinlock guards for zone lock" (Dmitry Ilvokhin) Switch zone->lock handling over to using the guard() mechanisms - "mm/filemap: tighten mmap_miss hit accounting" (fujunjie) Fix a flaw where the mmap_miss counter over-credited page cache hits during fault-arounds and page-fault retries. This results in significant reduction of redundant synchronous mmap readahead I/O, drastically cutting down execution time and gigabytes read for sparse random or strided memory access workloads - "selftests/cgroup: Fix false positive failures in test_percpu_basic" (Li Wang) Fix a couple of false-positives in the cgroup kmem selftests - "mm/damon/reclaim: support monitoring intervals auto-tuning" (SeongJae Park) Add a new parameter to DAMON permitting DAMON_RECLAIM to automatically tune DAMON's sampling and aggregation intervals - "mm/damon/stat: add kdamond_pid parameter" (SeongJae Park) Change DAMON_STAT to provide the pid of its kdamond - "mm/kmemleak: dedupe verbose scan output" (Breno Leitao) Remove large amounts of duplicated backtraces from the verbose-mode kmemleak output - "mm: remove CONFIG_HAVE_BOOTMEM_INFO_NODE (Part 1)" (David Hildenbrand) Reduce our use of CONFIG_HAVE_BOOTMEM_INFO_NODE, with a view to removing it entirely in a later series - "mm/damon: validate min_region_size to be power of 2" (Liew Rui Yan) Prevent users from passing a non-power-of-2 value of `addr_unit', as this later results in undesirable behavior - "mm: document read_pages and simplify usage" (Frederick Mayle) - "tools/mm/page-types: Fix misc bugs" (Ye Liu) Fix three issues in tools/mm/page-types.c - "mm: misc cleanups from __GFP_UNMAPPED series" (Brendan Jackman) Implement several cleanups in the page allocator and related code - "mm, swap: swap table phase IV: unify allocation" (Kairui Song) Unify the allocation and charging of anon and shmem swap in folios, provides better synchronization, consolidates the metadata management, hence dropping the static array and map, and improves performance - "mm/damon: introduce data attributes monitoring" (SeongJae Park( Extend DAMON to monitor general data attributes other than accesses - "mm/vmalloc: free unused pages on vrealloc() shrink" (Shivam Kalra) Implement the TODO in vrealloc() to unmap and free unused pages when shrinking across a page boundary - "mm/damon: documentation and comment fixes" (niecheng) - "remove mmap_action success, error hooks" (Lorenzo Stoakes) Eliminate custom hooks from mmap_action by removing the problematic success_hook which allowed drivers to improperly access uninitialized VMAs. It replaces the error_hook with a simple error-code field and updates the memory char driver accordingly - "mm/damon: minor improvements for code readability and tests" (SeongJae Park) - "mm/damon: fix macro arguments and clarify quota goals doc" (Maksym Shcherba) - "userfaultfd: merge fs/userfaultfd.c into mm/userfaultfd.c" (Mike Rapoport) - "mm/mglru: improve reclaim loop and dirty folio" (Kairui Song and others) Clean up and slightly improves MGLRU's reclaim loop and dirty writeback handling. Large performance improvements are measured - "use vma locks for proc/pid/{smaps|numa_maps} reads" (Suren Baghdasaryan) Use per-vma locks when reading /proc/pid/smaps and numa_maps similar to reduce contention on central mmap_lock - "refactors thpsize_shmem_enabled_store() and thpsize_shmem_enabled_show()" (Ran Xiaokai) Some cleanup work in the THP code - "selftests/memfd: fix compilation warnings" (Konstantin Khorenko) Fix a few build glitches in the memfd selftest code. - "memcg: shrink obj_stock_pcp and cache multiple objcgs" (Shakeel Butt) Resolve a 68% performance regression caused by NUMA-node cache thrashing around struct obj_stock_pcp by shrinking its existing fields and expanding it into a multi-slot array that caches up to five obj_cgroup pointers per CPU, allowing per-node variants of the same memcg to coexist within a single 64-byte cache line. - "zram: writeback fixes" (Sergey Senozhatsky) address a couple of unrelated zram writeback issues - "mm: switch THP shrinker to list_lru" (Johannes Weiner) Resolve NUMA-awareness issues and streamlines callsite interaction by refactoring and extending the list_lru API to completely replace the complex, open-coded deferred split queue for Transparent Huge Pages - "mm: improve large folio readahead for exec memory" (Usama Arif) Improve large-folio readahead on systems like 64K-page arm64 by preventing the mmap_miss check from permanently disabling target-oriented VM_EXEC readahead, and by generalizing the force_thp_readahead gate to support mappings with any usefully large maximum folio order under the cache cap. - "userfaultfd/pagemap: pre-existing fixes" (Kiryl Shutsemau) Fix a bunch of minor issues in the userfaultfd/pagemap, all of which were flagged by Sashiko review of proposed new material - "mm/sparse-vmemmap: Provide generic vmemmap_set_pmd() and vmemmap_check_pmd()" (Muchun Song) Provide generic versions of these two functions so the four arch-specific implementations can be removed. - "mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device" (Youngjun Park) Address a uswsusp-vs-swapoff race and reduces the swap device reference taking/releasing frequency. - "mm/hmm: A fix and a selftest" (Dev Jain) * tag 'mm-stable-2026-06-18-09-26' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (321 commits) selftests/mm/hmm-tests: test pagemap reads of PMD device-private entries fs/proc/task_mmu: do not warn on seeing non-migration pmd entry lib/test_hmm: check alloc_page_vma() return value and handle OOM mm/compaction: cap compact_gap() at COMPACT_CLUSTER_MAX mm/swap: remove redundant swap device reference in alloc/free mm/swap, PM: hibernate: fix swapoff race in uswsusp by pinning swap device mm/filemap: use folio_next_index() for start vmalloc: fix NULL pointer dereference in is_vm_area_hugepages() sparc/mm: drop vmemmap_check_pmd helper and use generic code loongarch/mm: drop vmemmap_check_pmd helper and use generic code riscv/mm: drop vmemmap_pmd helpers and use generic code arm64/mm: drop vmemmap_pmd helpers and use generic code mm/sparse-vmemmap: provide generic vmemmap_set_pmd() and vmemmap_check_pmd() rust: page: mark Page::nid as inline userfaultfd: build __VMA_UFFD_FLAGS from config-gated masks userfaultfd: gate must_wait writability check on pte_present() mm/huge_memory: preserve pmd_swp_uffd_wp on device-private PMD downgrade fs/proc/task_mmu: fix hugetlb self-deadlock in pagemap_scan_pte_hole() fs/proc/task_mmu: use huge_page_size() in pagemap_scan_hugetlb_entry() fs/proc/task_mmu: fix make_uffd_wp_huge_pte() prot-update race ...
2026-06-17Merge tag 'cgroup-for-7.2' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - Last cycle deferred css teardown on cgroup removal until the cgroup depopulated, so a css is not taken offline while tasks can still reference it. Disabling a controller through cgroup.subtree_control still had the same problem. This reworks the deferral from per-cgroup to per-css so that path is covered too. - New RDMA controller monitoring files: rdma.peak for per-device peak usage and rdma.events / rdma.events.local for resource-limit exhaustion. The max-limit parser was rewritten, fixing two input parsing bugs. - cpuset: fix a sched-domain leak on the domain-rebuild failure path and skip a redundant hardwall ancestor scan on v2. - Misc: pair the remaining lockless cgroup.max.* reads with WRITE_ONCE, assorted selftest robustness fixes, and doc path corrections. * tag 'cgroup-for-7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (22 commits) cgroup: Migrate tasks to the root css when a controller is rebound docs: cgroup: Fix stale source file paths cgroup/cpuset: Free sched domains on rebuild guard failure cgroup: pair max limit READ_ONCE() with WRITE_ONCE() selftests/cgroup: enable memory controller in hugetlb memcg test cgroup/rdma: Drop unnecessary READ_ONCE() on event counters cgroup: Defer kill_css_finish() in cgroup_apply_control_disable() cgroup: Add per-subsys-css kill_css_finish deferral cgroup: Move populated counters to cgroup_subsys_state cgroup: Annotate unlocked nr_populated_* accesses with READ_ONCE/WRITE_ONCE cgroup: Inline cgroup_has_tasks() in cgroup.h cgroup/rdma: document rdma.peak, rdma.events and rdma.events.local cgroup/rdma: add rdma.events.local for per-cgroup allocation failure attribution cgroup/rdma: add rdma.events to track resource limit exhaustion cgroup/rdma: add rdma.peak for per-device peak usage tracking selftests/cgroup: check malloc return value in alloc_anon functions cgroup/cpuset: Skip hardwall ancestor scan in cpuset v2 in cpuset_current_node_allowed() selftests/cgroup: fix misleading debug message in test_cgfreezer_time_child selftests/cgroup: fix child process escaping to parent cleanup in test_cpucg_nice selftests/cgroup: Add NULL check after malloc in cgroup_util.c ...
2026-05-28selftests/cgroup: include slab in test_percpu_basic memory checkLi Wang
test_percpu_basic() currently compares memory.current against only memory.stat:percpu after creating 1000 child cgroups. Observed failure: #./test_kmem ok 1 test_kmem_basic ok 2 test_kmem_memcg_deletion ok 3 test_kmem_proc_kpagecgroup ok 4 test_kmem_kernel_stacks ok 5 test_kmem_dead_cgroups memory.current 11530240 percpu 8440000 not ok 6 test_percpu_basic That assumption is too strict: child cgroup creation also allocates slab-backed metadata, so memory.current is expected to be larger than percpu alone. One visible path is: cgroup_mkdir() cgroup_create() cgroup_addrm_file() cgroup_add_file() __kernfs_create_file() __kernfs_new_node() kmem_cache_zalloc() These kernfs allocations are charged as slab and show up in memory.stat:slab. Update the check to compare memory.current against (percpu + slab) within MAX_VMSTAT_ERROR, and print slab/delta in the failure message to improve diagnostics. Link: https://lore.kernel.org/20260501022058.18024-3-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Reviewed-by: Waiman Long <longman@redhat.com> Cc: Christoph Lameter <cl@linux.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Cc: Sayali Patil <sayalip@linux.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: fix hardcoded page size in test_percpu_basicLi Wang
Patch series "selftests/cgroup: Fix false positive failures in test_percpu_basic", v2. This patch series addresses two separate issues that cause false positive failures in the test_percpu_basic test within the cgroup kmem selftests. The first issue stems from a hardcoded assumption about the system page size, which breaks the test on architectures with larger page sizes. The second issue is an overly strict memory check that fails to account for the slab metadata allocated during cgroup creation. This patch (of 2): MAX_VMSTAT_ERROR uses a hardcoded page size of 4096, which assumes 4K pages. This causes test_percpu_basic to fail on systems where the kernel is configured with a larger page size, such as aarch64 systems using 16K or 64K pages, where the maximum permissible discrepancy between memory.current and percpu charges is proportionally larger. Replace the hardcoded 4096 with sysconf(_SC_PAGESIZE) to correctly derive the page size at runtime regardless of the underlying architecture or kernel configuration. Link: https://lore.kernel.org/20260501022058.18024-1-li.wang@linux.dev Link: https://lore.kernel.org/20260501022058.18024-2-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Waiman Long <longman@redhat.com> Reviewed-by: Sayali Patil <sayalip@linux.ibm.com> Cc: Christoph Lameter <cl@linux.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Shakeel Butt <shakeelb@google.com> Cc: Tejun Heo <tj@kernel.org> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: test_zswap: wait for asynchronous writebackLi Wang
zswap writeback is asynchronous, but test_zswap.c checks writeback counters immediately after reclaim/trigger paths. On some platforms (e.g. ppc64le), this can race with background writeback and cause spurious failures even when behavior is correct. Add wait_for_writeback() to poll get_cg_wb_count() with a bounded timeout, and use it in: test_zswap_writeback_one() when writeback is expected test_no_invasive_cgroup_shrink() for the wb_group check This keeps the original before/after assertion style while making the tests robust against writeback completion latency. No test behavior change, selftest stability improvement only. Link: https://lore.kernel.org/20260424040059.12940-9-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosry@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftest/cgroup: fix zswap attempt_writeback() on 64K pagesize systemLi Wang
In attempt_writeback(), a memsize of 4M only covers 64 pages on 64K page size systems. When memory.reclaim is called, the kernel prefers reclaiming clean file pages (binary, libc, linker, etc.) over swapping anonymous pages. With only 64 pages of anonymous memory, the reclaim target can be largely or entirely satisfied by dropping file pages, resulting in very few or zero anonymous pages being pushed into zswap. This causes zswap_usage to be extremely small or zero, making zswap_usage/4 insufficient to create meaningful writeback pressure. The test then fails because no writeback is triggered. On 4K page size systems this is not an issue because 4M covers 1024 pages, and file pages are a small fraction of the reclaim target. Fix this by: - Always allocating 1024 pages regardless of page size. This ensures enough anonymous pages to reliably populate zswap and trigger writeback, while keeping the original 4M allocation on 4K systems. - Setting zswap.max to zswap_usage/4 instead of zswap_usage/2 to create stronger writeback pressure, ensuring reclaim reliably triggers writeback even on large page size systems. === Error Log === # uname -rm 6.12.0-211.el10.ppc64le ppc64le # getconf PAGESIZE 65536 # ./test_zswap TAP version 13 1..7 ok 1 test_zswap_usage ok 2 test_swapin_nozswap ok 3 test_zswapin not ok 4 test_zswap_writeback_enabled ... Link: https://lore.kernel.org/20260424040059.12940-8-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Yosry Ahmed <yosry@kernel.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftest/cgroup: fix zswap test_no_invasive_cgroup_shrink on large pagesize ↵Li Wang
system test_no_invasive_cgroup_shrink sets up two cgroups: wb_group, which is expected to trigger zswap writeback, and a control group (renamed to zw_group), which should only have pages sitting in zswap without any writeback. There are two problems with the current test: 1) The data patterns are reversed. wb_group uses allocate_bytes(), which writes only a single byte per page — trivially compressible, especially by zstd — so compressed pages fit within zswap.max and writeback is never triggered. Meanwhile, the control group uses getrandom() to produce hard-to-compress data, but it is the group that does *not* need writeback. 2) The test uses fixed sizes (10K zswap.max, 10MB allocation) that are too small on systems with large PAGE_SIZE (e.g. 64K), failing to build enough memory pressure to trigger writeback reliably. Fix both issues by: - Swapping the data patterns: fill wb_group pages with partially random data (getrandom for page_size/4 bytes) to resist compression and trigger writeback, and fill zw_group pages with simple repeated data to stay compressed in zswap. - Making all size parameters PAGE_SIZE-aware: set allocation size to PAGE_SIZE * 1024, memory.zswap.max to PAGE_SIZE, and memory.max to allocation_size / 2 for both cgroups. - Allocating memory inline instead of via cg_run() so the pages remain resident throughout the test. === Error Log === # getconf PAGESIZE 65536 # ./test_zswap TAP version 13 ... ok 5 test_zswap_writeback_disabled ok 6 # SKIP test_no_kmem_bypass not ok 7 test_no_invasive_cgroup_shrink Link: https://lore.kernel.org/20260424040059.12940-7-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosry@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: replace hardcoded page size values in test_zswapLi Wang
test_zswap uses hardcoded values of 4095 and 4096 throughout as page stride and page size, which are only correct on systems with a 4K page size. On architectures with larger pages (e.g., 64K on arm64 or ppc64), these constants cause memory to be touched at sub-page granularity, leading to inefficient access patterns and incorrect page count calculations, which can cause test failures. Replace all hardcoded 4095 and 4096 values with a global pagesize variable initialized from sysconf(_SC_PAGESIZE) at startup, and remove the redundant local sysconf() calls scattered across individual functions. No functional change on 4K page size systems. Link: https://lore.kernel.org/20260424040059.12940-6-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Yosry Ahmed <yosry@kernel.org> Reviewed-by: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Nhat Pham <nphamcs@gmail.com> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: rename PAGE_SIZE to BUF_SIZE in cgroup_utilLi Wang
The cgroup utility code defines a local PAGE_SIZE macro hardcoded to 4096, which is used primarily as a generic buffer size for reading cgroup and proc files. This naming is misleading because the value has nothing to do with the actual page size of the system. On architectures with larger pages (e.g., 64K on arm64 or ppc64), the name suggests a relationship that does not exist. Additionally, the name can shadow or conflict with PAGE_SIZE definitions from system headers, leading to confusion or subtle bugs. To resolve this, rename the macro to BUF_SIZE to accurately reflect its purpose as a general I/O buffer size. Furthermore, test_memcontrol currently relies on this hardcoded 4K value to stride through memory and trigger page faults. Update this logic to use the actual system page size dynamically. This micro-optimizes the memory faulting process by ensuring it iterates correctly and efficiently based on the underlying architecture's true page size. (This part from Waiman) Link: https://lore.kernel.org/20260424040059.12940-5-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Yosry Ahmed <yosryahmed@google.com> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Yosry Ahmed <yosry@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: use runtime page size for zswpin checkLi Wang
test_zswapin compares memory.stat:zswpin (counted in pages) against a byte threshold converted with PAGE_SIZE. In cgroup selftests, PAGE_SIZE is hardcoded to 4096, which makes the conversion wrong on systems with non-4K base pages (e.g. 64K). As a result, the test requires too many pages to pass and fails spuriously even when zswap is working. Use sysconf(_SC_PAGESIZE) for the zswpin threshold conversion so the check matches the actual system page size. Link: https://lore.kernel.org/20260424040059.12940-4-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Reviewed-by: Yosry Ahmed <yosry@kernel.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: avoid OOM in test_swapin_nozswapLi Wang
test_swapin_nozswap can hit OOM before reaching its assertions on some setups. The test currently sets memory.max=8M and then allocates/reads 32M with memory.zswap.max=0, which may over-constrain reclaim and kill the workload process. Replace hardcoded sizes with PAGE_SIZE-based values: - control_allocation_size = PAGE_SIZE * 512 - memory.max = control_allocation_size * 3 / 4 - minimum expected swap = control_allocation_size / 4 This keeps the test pressure model intact (allocate/read beyond memory.max to force swap-in/out) while making it more robust across different environments. The test intent is unchanged: confirm that swapping occurs while zswap remains unused when memory.zswap.max=0. === Error Logs === # ./test_zswap TAP version 13 1..7 ok 1 test_zswap_usage not ok 2 test_swapin_nozswap ... # dmesg [271641.879153] test_zswap invoked oom-killer: gfp_mask=0xcc0(GFP_KERNEL), order=0, oom_score_adj=0 [271641.879168] CPU: 1 UID: 0 PID: 177372 Comm: test_zswap Kdump: loaded Not tainted 6.12.0-211.el10.ppc64le #1 VOLUNTARY [271641.879171] Hardware name: IBM,9009-41A POWER9 (architected) 0x4e0202 0xf000005 of:IBM,FW940.02 (UL940_041) hv:phyp pSeries [271641.879173] Call Trace: [271641.879174] [c00000037540f730] [c00000000127ec44] dump_stack_lvl+0x88/0xc4 (unreliable) [271641.879184] [c00000037540f760] [c0000000005cc594] dump_header+0x5c/0x1e4 [271641.879188] [c00000037540f7e0] [c0000000005cb464] oom_kill_process+0x324/0x3b0 [271641.879192] [c00000037540f860] [c0000000005cbe48] out_of_memory+0x118/0x420 [271641.879196] [c00000037540f8f0] [c00000000070d8ec] mem_cgroup_out_of_memory+0x18c/0x1b0 [271641.879200] [c00000037540f990] [c000000000713888] try_charge_memcg+0x598/0x890 [271641.879204] [c00000037540fa70] [c000000000713dbc] charge_memcg+0x5c/0x110 [271641.879207] [c00000037540faa0] [c0000000007159f8] __mem_cgroup_charge+0x48/0x120 [271641.879211] [c00000037540fae0] [c000000000641914] alloc_anon_folio+0x2b4/0x5a0 [271641.879215] [c00000037540fb60] [c000000000641d58] do_anonymous_page+0x158/0x6b0 [271641.879218] [c00000037540fbd0] [c000000000642f8c] __handle_mm_fault+0x4bc/0x910 [271641.879221] [c00000037540fcf0] [c000000000643500] handle_mm_fault+0x120/0x3c0 [271641.879224] [c00000037540fd40] [c00000000014bba0] ___do_page_fault+0x1c0/0x980 [271641.879228] [c00000037540fdf0] [c00000000014c44c] hash__do_page_fault+0x2c/0xc0 [271641.879232] [c00000037540fe20] [c0000000001565d8] do_hash_fault+0x128/0x1d0 [271641.879236] [c00000037540fe50] [c000000000008be0] data_access_common_virt+0x210/0x220 [271641.879548] Tasks state (memory values in pages): ... [271641.879550] [ pid ] uid tgid total_vm rss rss_anon rss_file rss_shmem pgtables_bytes swapents oom_score_adj name [271641.879555] [ 177372] 0 177372 571 0 0 0 0 51200 96 0 test_zswap [271641.879562] oom-kill:constraint=CONSTRAINT_MEMCG,nodemask=(null),cpuset=/,mems_allowed=0,oom_memcg=/no_zswap_test,task_memcg=/no_zswap_test,task=test_zswap,pid=177372,uid=0 [271641.879578] Memory cgroup out of memory: Killed process 177372 (test_zswap) total-vm:36544kB, anon-rss:0kB, file-rss:0kB, shmem-rss:0kB, UID:0 pgtables:50kB oom_score_adj:0 Link: https://lore.kernel.org/20260424040059.12940-3-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Yosry Ahmed <yosry@kernel.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-28selftests/cgroup: skip test_zswap if zswap is globally disabledLi Wang
Patch series "selftests/cgroup: improve zswap tests robustness and support large page sizes", v7. This patchset aims to fix various spurious failures and improve the overall robustness of the cgroup zswap selftests. The primary motivation is to make the tests compatible with architectures that use non-4K page sizes (such as 64K on ppc64le and arm64). Currently, the tests rely heavily on hardcoded 4K page sizes and fixed memory limits. On 64K page size systems, these hardcoded values lead to sub-page granularity accesses, incorrect page count calculations, and insufficient memory pressure to trigger zswap writeback, ultimately causing the tests to fail. Additionally, this series addresses OOM kills occurring in test_swapin_nozswap by dynamically scaling memory limits, and prevents spurious test failures when zswap is built into the kernel but globally disabled. This patch (of 8): test_zswap currently only checks whether zswap is present by testing /sys/module/zswap. This misses the runtime global state exposed in /sys/module/zswap/parameters/enabled. When zswap is built/loaded but globally disabled, the zswap cgroup selftests run in an invalid environment and may fail spuriously. Check the runtime enabled state before running the tests: - skip if zswap is not configured, - fail if the enabled knob cannot be read, - skip if zswap is globally disabled. Also print a hint in the skip message on how to enable zswap. Link: https://lore.kernel.org/20260424040059.12940-1-li.wang@linux.dev Link: https://lore.kernel.org/20260424040059.12940-2-li.wang@linux.dev Signed-off-by: Li Wang <li.wang@linux.dev> Acked-by: Yosry Ahmed <yosry@kernel.org> Acked-by: Nhat Pham <nphamcs@gmail.com> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Tejun Heo <tj@kernel.org> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shakeel Butt <shakeel.butt@linux.dev> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Jiayuan Chen <jiayuan.chen@linux.dev> Cc: Waiman Long <longman@redhat.com> Cc: Yosry Ahmed <yosryahmed@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-05-27cgroup/cpuset: Add test cases for sibling CPU exclusion on partition updateSun Shaojie
When sibling CPU exclusion occurs, a partition's effective_xcpus may be a subset of its user_xcpus. The partcmd_update path must use effective_xcpus instead of user_xcpus when calculating CPUs to return to or request from the parent. Add two test cases to verify this behavior: 1) Narrowing cpuset.cpus to only the sibling-excluded CPUs should not return CPUs to parent that the partition never actually owned. 2) Expanding cpuset.cpus after a sibling becomes a member should correctly request the additional CPUs from parent. Co-developed-by: Zhang Guopeng <zhangguopeng@kylinos.cn> Signed-off-by: Zhang Guopeng <zhangguopeng@kylinos.cn> Signed-off-by: Sun Shaojie <sunshaojie@kylinos.cn> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-22selftests/cgroup: enable memory controller in hugetlb memcg testGuopeng Zhang
test_hugetlb_memcg creates a child cgroup and then writes memory.max and memory.swap.max. When the test is run standalone, the memory controller may not be enabled in the test root cgroup's subtree_control. In that case, the child cgroup is created without the memory control files, and the test fails during setup before reaching the hugetlb memcg accounting checks. Skip the test when the memory controller is unavailable. Otherwise, enable it in subtree_control before creating the test cgroup. Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn> Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-13selftests/cgroup: Fix error path leaks in test_percpu_basicYu Miao
When cg_name_indexed() returns NULL partway through the child creation loop, the code returned -1 without running cleanup_children and cleanup. That left the `parent` pathname allocation unreleased and did not remove child cgroup directories already created under the parent. Fix by jumping to cleanup_children instead of returning. When cg_create() fails, `child` (the pathname from cg_name_indexed()) was not freed before cleanup_children. Fix by freeing `child` before branching to cleanup_children. Fixes: 90631e1dea55 ("kselftests: cgroup: add perpcu memory accounting test") Signed-off-by: Yu Miao <yumiao@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-12selftests/cgroup: check malloc return value in alloc_anon functionsHongfu Li
The alloc_anon() function calls malloc() without checking for a NULL return. If memory allocation fails, a NULL pointer dereference will occur when accessing the buffer. Add proper error handling to return -1 when malloc() fails in all four alloc_anon variants: - alloc_anon() - alloc_anon_50M_check() - alloc_anon_noexit() - alloc_anon_50M_check_swap() Signed-off-by: Hongfu Li <lihongfu@kylinos.cn> Reviewed-by: Vishal Moola <vishal.moola@gmail.com> Reviewed-by: Muchun Song <muchun.song@linux.dev> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-10Merge branch 'for-7.1-fixes' into for-7.2Tejun Heo
Pull to receive dde2f938d02f ("cgroup/cpuset: move PF_EXITING check before __GFP_HARDWALL in cpuset_current_node_allowed()") as a dependency for an upcoming patch in the same function. Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-10selftests/cgroup: fix misleading debug message in test_cgfreezer_time_childTao Cui
The debug message says "Expect ctime <= ptime" when the test actually expects ctime > ptime (child's freeze time should exceed parent's, which is zero). Fix the message to match the actual expectation. Signed-off-by: Tao Cui <cuitao@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-10selftests/cgroup: fix child process escaping to parent cleanup in ↵Tao Cui
test_cpucg_nice In test_cpucg_nice, the forked child process incorrectly jumps to the parent's cleanup label on cg_write failure. This causes the child to attempt cg_destroy on cgroups the parent is still using, and then return to main() to continue executing tests as if it were the parent. Replace goto cleanup with exit(EXIT_FAILURE) in the child process. Signed-off-by: Tao Cui <cuitao@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-10selftests/cgroup: Add NULL check after malloc in cgroup_util.cHongfu Li
Add NULL checks after malloc() in three helper functions to prevent NULL pointer dereference on memory allocation failure. - cg_name() - cg_name_indexed() - cg_control() These functions allocate memory with malloc() but previously called snprintf() unconditionally, which would trigger undefined behavior if allocation fails. Signed-off-by: Hongfu Li <lihongfu@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-10selftests/cgroup: Fix string comparison in write_testHongfu Li
Use string comparison (!=) instead of numeric comparison (-ne) for cpuset values like "0-1". For example: $ [[ "0-1" != "2-3" ]] && echo "true" || echo "false" true $ [[ "0-1" -ne "2-3" ]] && echo "true" || echo "false" false Signed-off-by: Hongfu Li <lihongfu@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-10selftests/cgroup: Fix cg_read_strcmp() empty string comparisonHongfu Li
cg_read_strcmp() allocated a buffer sized to strlen(expected) + 1, then passed it to read_text() which calls read(fd, buf, size-1). When comparing against an empty string (""), strlen("") = 0 gives a 1-byte buffer, and read() is asked to read 0 bytes. The file content is never actually read, so strcmp("", buf) always returns 0 regardless of the real content. This caused cg_test_proc_killed() to always report the cgroup as empty immediately, making OOM tests pass without verifying that processes were killed. Signed-off-by: Hongfu Li <lihongfu@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-05-08selftests/cgroup: Fix incorrect variable check in online_cpus()Hongfu Li
"OFFLINE_CPUS" is a literal string that is always non-empty. It should be "$OFFLINE_CPUS" to check the variable's value instead. Signed-off-by: Hongfu Li <lihongfu@kylinos.cn> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-04-15Merge tag 'mm-stable-2026-04-13-21-45' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull MM updates from Andrew Morton: - "maple_tree: Replace big node with maple copy" (Liam Howlett) Mainly prepararatory work for ongoing development but it does reduce stack usage and is an improvement. - "mm, swap: swap table phase III: remove swap_map" (Kairui Song) Offers memory savings by removing the static swap_map. It also yields some CPU savings and implements several cleanups. - "mm: memfd_luo: preserve file seals" (Pratyush Yadav) File seal preservation to LUO's memfd code - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan Chen) Additional userspace stats reportng to zswap - "arch, mm: consolidate empty_zero_page" (Mike Rapoport) Some cleanups for our handling of ZERO_PAGE() and zero_pfn - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu Han) A robustness improvement and some cleanups in the kmemleak code - "Improve khugepaged scan logic" (Vernon Yang) Improve khugepaged scan logic and reduce CPU consumption by prioritizing scanning tasks that access memory frequently - "Make KHO Stateless" (Jason Miu) Simplify Kexec Handover by transitioning KHO from an xarray-based metadata tracking system with serialization to a radix tree data structure that can be passed directly to the next kernel - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas Ballasi and Steven Rostedt) Enhance vmscan's tracepointing - "mm: arch/shstk: Common shadow stack mapping helper and VM_NOHUGEPAGE" (Catalin Marinas) Cleanup for the shadow stack code: remove per-arch code in favour of a generic implementation - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin) Fix a WARN() which can be emitted the KHO restores a vmalloc area - "mm: Remove stray references to pagevec" (Tal Zussman) Several cleanups, mainly udpating references to "struct pagevec", which became folio_batch three years ago - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl Shutsemau) Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail pages encode their relationship to the head page - "mm/damon/core: improve DAMOS quota efficiency for core layer filters" (SeongJae Park) Improve two problematic behaviors of DAMOS that makes it less efficient when core layer filters are used - "mm/damon: strictly respect min_nr_regions" (SeongJae Park) Improve DAMON usability by extending the treatment of the min_nr_regions user-settable parameter - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka) The proper fix for a previously hotfixed SMP=n issue. Code simplifications and cleanups ensued - "mm: cleanups around unmapping / zapping" (David Hildenbrand) A bunch of cleanups around unmapping and zapping. Mostly simplifications, code movements, documentation and renaming of zapping functions - "support batched checking of the young flag for MGLRU" (Baolin Wang) Batched checking of the young flag for MGLRU. It's part cleanups; one benchmark shows large performance benefits for arm64 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner) memcg cleanup and robustness improvements - "Allow order zero pages in page reporting" (Yuvraj Sakshith) Enhance free page reporting - it is presently and undesirably order-0 pages when reporting free memory. - "mm: vma flag tweaks" (Lorenzo Stoakes) Cleanup work following from the recent conversion of the VMA flags to a bitmap - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae Park) Add some more developer-facing debug checks into DAMON core - "mm/damon: test and document power-of-2 min_region_sz requirement" (SeongJae Park) An additional DAMON kunit test and makes some adjustments to the addr_unit parameter handling - "mm/damon/core: make passed_sample_intervals comparisons overflow-safe" (SeongJae Park) Fix a hard-to-hit time overflow issue in DAMON core - "mm/damon: improve/fixup/update ratio calculation, test and documentation" (SeongJae Park) A batch of misc/minor improvements and fixups for DAMON - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David Hildenbrand) Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code movement was required. - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky) A somewhat random mix of fixups, recompression cleanups and improvements in the zram code - "mm/damon: support multiple goal-based quota tuning algorithms" (SeongJae Park) Extend DAMOS quotas goal auto-tuning to support multiple tuning algorithms that users can select - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao) Fix the khugpaged sysfs handling so we no longer spam the logs with reams of junk when starting/stopping khugepaged - "mm: improve map count checks" (Lorenzo Stoakes) Provide some cleanups and slight fixes in the mremap, mmap and vma code - "mm/damon: support addr_unit on default monitoring targets for modules" (SeongJae Park) Extend the use of DAMON core's addr_unit tunable - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache) Cleanups to khugepaged and is a base for Nico's planned khugepaged mTHP support - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand) Code movement and cleanups in the memhotplug and sparsemem code - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup CONFIG_MIGRATION" (David Hildenbrand) Rationalize some memhotplug Kconfig support - "change young flag check functions to return bool" (Baolin Wang) Cleanups to change all young flag check functions to return bool - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh Law and SeongJae Park) Fix a few potential DAMON bugs - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo Stoakes) Convert a lot of the existing use of the legacy vm_flags_t data type to the new vma_flags_t type which replaces it. Mainly in the vma code. - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes) Expand the mmap_prepare functionality, which is intended to replace the deprecated f_op->mmap hook which has been the source of bugs and security issues for some time. Cleanups, documentation, extension of mmap_prepare into filesystem drivers - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes) Simplify and clean up zap_huge_pmd(). Additional cleanups around vm_normal_folio_pmd() and the softleaf functionality are performed. * tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits) mm: fix deferred split queue races during migration mm/khugepaged: fix issue with tracking lock mm/huge_memory: add and use has_deposited_pgtable() mm/huge_memory: add and use normal_or_softleaf_folio_pmd() mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio() mm/huge_memory: separate out the folio part of zap_huge_pmd() mm/huge_memory: use mm instead of tlb->mm mm/huge_memory: remove unnecessary sanity checks mm/huge_memory: deduplicate zap deposited table call mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE() mm/huge_memory: add a common exit path to zap_huge_pmd() mm/huge_memory: handle buggy PMD entry in zap_huge_pmd() mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc mm/huge: avoid big else branch in zap_huge_pmd() mm/huge_memory: simplify vma_is_specal_huge() mm: on remap assert that input range within the proposed VMA mm: add mmap_action_map_kernel_pages[_full]() uio: replace deprecated mmap hook with mmap_prepare in uio_info drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare mm: allow handling of stacked mmap_prepare hooks in more drivers ...
2026-04-13Merge tag 'driver-core-7.1-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core Pull driver core updates from Danilo Krummrich: "debugfs: - Fix NULL pointer dereference in debugfs_create_str() - Fix misplaced EXPORT_SYMBOL_GPL for debugfs_create_str() - Fix soundwire debugfs NULL pointer dereference from uninitialized firmware_file device property: - Make fwnode flags modifications thread safe; widen the field to unsigned long and use set_bit() / clear_bit() based accessors - Document how to check for the property presence devres: - Separate struct devres_node from its "subclasses" (struct devres, struct devres_group); give struct devres_node its own release and free callbacks for per-type dispatch - Introduce struct devres_action for devres actions, avoiding the ARCH_DMA_MINALIGN alignment overhead of struct devres - Export struct devres_node and its init/add/remove/dbginfo primitives for use by Rust Devres<T> - Fix missing node debug info in devm_krealloc() - Use guard(spinlock_irqsave) where applicable; consolidate unlock paths in devres_release_group() driver_override: - Convert PCI, WMI, vdpa, s390/cio, s390/ap, and fsl-mc to the generic driver_override infrastructure, replacing per-bus driver_override strings, sysfs attributes, and match logic; fixes a potential UAF from unsynchronized access to driver_override in bus match() callbacks - Simplify __device_set_driver_override() logic kernfs: - Send IN_DELETE_SELF and IN_IGNORED inotify events on kernfs file and directory removal - Add corresponding selftests for memcg platform: - Allow attaching software nodes when creating platform devices via a new 'swnode' field in struct platform_device_info - Add kerneldoc for struct platform_device_info software node: - Move software node initialization from postcore_initcall() to driver_init(), making it available early in the boot process - Move kernel_kobj initialization (ksysfs_init) earlier to support the above - Remove software_node_exit(); dead code in a built-in unit SoC: - Introduce of_machine_read_compatible() and of_machine_read_model() OF helpers and export soc_attr_read_machine() to replace direct accesses to of_root from SoC drivers; also enables CONFIG_COMPILE_TEST coverage for these drivers sysfs: - Constify attribute group array pointers to 'const struct attribute_group *const *' in sysfs functions, device_add_groups() / device_remove_groups(), and struct class Rust: - Devres: - Embed struct devres_node directly in Devres<T> instead of going through devm_add_action(), avoiding the extra allocation and the unnecessary ARCH_DMA_MINALIGN alignment - I/O: - Turn IoCapable from a marker trait into a functional trait carrying the raw I/O accessor implementation (io_read / io_write), providing working defaults for the per-type Io methods - Add RelaxedMmio wrapper type, making relaxed accessors usable in code generic over the Io trait - Remove overloaded per-type Io methods and per-backend macros from Mmio and PCI ConfigSpace - I/O (Register): - Add IoLoc trait and generic read/write/update methods to the Io trait, making I/O operations parameterizable by typed locations - Add register! macro for defining hardware register types with typed bitfield accessors backed by Bounded values; supports direct, relative, and array register addressing - Add write_reg() / try_write_reg() and LocatedRegister trait - Update PCI sample driver to demonstrate the register! macro Example: ``` register! { /// UART control register. CTRL(u32) @ 0x18 { /// Receiver enable. 19:19 rx_enable => bool; /// Parity configuration. 14:13 parity ?=> Parity; } /// FIFO watermark and counter register. WATER(u32) @ 0x2c { /// Number of datawords in the receive FIFO. 26:24 rx_count; /// RX interrupt threshold. 17:16 rx_water; } } impl WATER { fn rx_above_watermark(&self) -> bool { self.rx_count() > self.rx_water() } } fn init(bar: &pci::Bar<BAR0_SIZE>) { let water = WATER::zeroed() .with_const_rx_water::<1>(); // > 3 would not compile bar.write_reg(water); let ctrl = CTRL::zeroed() .with_parity(Parity::Even) .with_rx_enable(true); bar.write_reg(ctrl); } fn handle_rx(bar: &pci::Bar<BAR0_SIZE>) { if bar.read(WATER).rx_above_watermark() { // drain the FIFO } } fn set_parity(bar: &pci::Bar<BAR0_SIZE>, parity: Parity) { bar.update(CTRL, |r| r.with_parity(parity)); } ``` - IRQ: - Move 'static bounds from where clauses to trait declarations for IRQ handler traits - Misc: - Enable the generic_arg_infer Rust feature - Extend Bounded with shift operations, single-bit bool conversion, and const get() Misc: - Make deferred_probe_timeout default a Kconfig option - Drop auxiliary_dev_pm_ops; the PM core falls back to driver PM callbacks when no bus type PM ops are set - Add conditional guard support for device_lock() - Add ksysfs.c to the DRIVER CORE MAINTAINERS entry - Fix kernel-doc warnings in base.h - Fix stale reference to memory_block_add_nid() in documentation" * tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core: (67 commits) bus: fsl-mc: use generic driver_override infrastructure s390/ap: use generic driver_override infrastructure s390/cio: use generic driver_override infrastructure vdpa: use generic driver_override infrastructure platform/wmi: use generic driver_override infrastructure PCI: use generic driver_override infrastructure driver core: make software nodes available earlier software node: remove software_node_exit() kernel: ksysfs: initialize kernel_kobj earlier MAINTAINERS: add ksysfs.c to the DRIVER CORE entry drivers/base/memory: fix stale reference to memory_block_add_nid() device property: Document how to check for the property presence soundwire: debugfs: initialize firmware_file to empty string debugfs: fix placement of EXPORT_SYMBOL_GPL for debugfs_create_str() debugfs: check for NULL pointer in debugfs_create_str() driver core: Make deferred_probe_timeout default a Kconfig option driver core: simplify __device_set_driver_override() clearing logic driver core: auxiliary bus: Drop auxiliary_dev_pm_ops device property: Make modifications of fwnode "flags" thread safe rust: devres: embed struct devres_node directly ...
2026-04-05selftest: memcg: skip memcg_sock test if address family not supportedWaiman Long
The test_memcg_sock test in memcontrol.c sets up an IPv6 socket and send data over it to consume memory and verify that memory.stat.sock and memory.current values are close. On systems where IPv6 isn't enabled or not configured to support SOCK_STREAM, the test_memcg_sock test always fails. When the socket() call fails, there is no way we can test the memory consumption and verify the above claim. I believe it is better to just skip the test in this case instead of reporting a test failure hinting that there may be something wrong with the memcg code. Link: https://lkml.kernel.org/r/20260311200526.885899-1-longman@redhat.com Fixes: 5f8f019380b8 ("selftests: cgroup/memcontrol: add basic test for socket accounting") Signed-off-by: Waiman Long <longman@redhat.com> Acked-by: Michal Koutný <mkoutny@suse.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Mike Rapoport <rppt@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shuah Khan <shuah@kernel.org> Cc: Tejun Heo <tj@kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-04-05selftests/cgroup: add test for zswap incompressible pagesJiayuan Chen
Add test_zswap_incompressible() to verify that the zswap_incomp memcg stat correctly tracks incompressible pages. The test allocates memory filled with random data from /dev/urandom, which cannot be effectively compressed by zswap. When this data is swapped out to zswap, it should be stored as-is and tracked by the zswap_incomp counter. The test verifies that: 1. Pages are swapped out to zswap (zswpout increases) 2. Incompressible pages are tracked (zswap_incomp increases) test: dd if=/dev/zero of=/swapfile bs=1M count=2048 chmod 600 /swapfile mkswap /swapfile swapon /swapfile echo Y > /sys/module/zswap/parameters/enabled ./test_zswap TAP version 13 1..8 ok 1 test_zswap_usage ok 2 test_swapin_nozswap ok 3 test_zswapin ok 4 test_zswap_writeback_enabled ok 5 test_zswap_writeback_disabled ok 6 test_no_kmem_bypass ok 7 test_no_invasive_cgroup_shrink ok 8 test_zswap_incompressible Totals: pass:8 fail:0 xfail:0 xpass:0 skip:0 error:0 Link: https://lkml.kernel.org/r/20260213071827.5688-3-jiayuan.chen@linux.dev Signed-off-by: Jiayuan Chen <jiayuan.chen@shopee.com> Acked-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Nhat Pham <nphamcs@gmail.com> Reviewed-by: SeongJae Park <sj@kernel.org> Cc: Chengming Zhou <chengming.zhou@linux.dev> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Michal Hocko <mhocko@kernel.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: Muchun Song <muchun.song@linux.dev> Cc: Roman Gushchin <roman.gushchin@linux.dev> Cc: Shuah Khan <shuah@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Yosry Ahmed <yosry.ahmed@linux.dev> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2026-03-24selftests/cgroup: Don't require synchronous populated update on task exitTejun Heo
test_cgcore_populated (test_core) and test_cgkill_{simple,tree,forkbomb} (test_kill) check cgroup.events "populated 0" immediately after reaping child tasks with waitpid(). This used to work because cgroup_task_exit() in do_exit() unlinked tasks from css_sets before exit_notify() woke up waitpid(). d245698d727a ("cgroup: Defer task cgroup unlink until after the task is done switching out") moved the unlink to cgroup_task_dead() in finish_task_switch(), which runs after exit_notify(). The populated counter is now decremented after the parent's waitpid() can return, so there is no longer a synchronous ordering guarantee. On PREEMPT_RT, where cgroup_task_dead() is further deferred through lazy irq_work, the race window is even larger. The synchronous populated transition was never part of the cgroup interface contract - it was an implementation artifact. Use cg_read_strcmp_wait() which retries for up to 1 second, matching what these tests actually need to verify: that the cgroup eventually becomes unpopulated after all tasks exit. Fixes: d245698d727a ("cgroup: Defer task cgroup unlink until after the task is done switching out") Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: Tejun Heo <tj@kernel.org> Tested-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Cc: Christian Brauner <brauner@kernel.org> Cc: cgroups@vger.kernel.org
2026-03-12selftests: memcg: Add tests for IN_DELETE_SELF and IN_IGNOREDT.J. Mercier
Add two new tests that verify inotify events are sent when memcg files or directories are removed with rmdir. Signed-off-by: T.J. Mercier <tjmercier@google.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Amir Goldstein <amir73il@gmail.com> Tested-by: syzbot@syzkaller.appspotmail.com Link: https://patch.msgid.link/20260225223404.783173-4-tjmercier@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2026-02-23cgroup/cpuset: Defer housekeeping_update() calls from CPU hotplug to workqueueWaiman Long
The cpuset_handle_hotplug() may need to invoke housekeeping_update(), for instance, when an isolated partition is invalidated because its last active CPU has been put offline. As we are going to enable dynamic update to the nozh_full housekeeping cpumask (HK_TYPE_KERNEL_NOISE) soon with the help of CPU hotplug, allowing the CPU hotplug path to call into housekeeping_update() directly from update_isolation_cpumasks() will likely cause deadlock. So we have to defer any call to housekeeping_update() after the CPU hotplug operation has finished. This is now done via the workqueue where the update_hk_sched_domains() function will be invoked via the hk_sd_workfn(). An concurrent cpuset control file write may have executed the required update_hk_sched_domains() function before the work function is called. So the work function call may become a no-op when it is invoked. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-02-23kselftest/cgroup: Simplify test_cpuset_prs.sh by removing "S+" commandWaiman Long
The "S+" command is used in the test matrix to enable the cpuset controller. However this can be done automatically and we never use the "S-" command to disable cpuset controller. Simplify the test matrix and reduce clutter by removing the command and doing that automatically. There is no functional change to the test cases. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-01-12cgroup/cpuset: Move the v1 empty cpus/mems check to cpuset1_validate_change()Waiman Long
As stated in commit 1c09b195d37f ("cpuset: fix a regression in validating config change"), it is not allowed to clear masks of a cpuset if there're tasks in it. This is specific to v1 since empty "cpuset.cpus" or "cpuset.mems" will cause the v2 cpuset to inherit the effective CPUs or memory nodes from its parent. So it is OK to have empty cpus or mems even if there are tasks in the cpuset. Move this empty cpus/mems check in validate_change() to cpuset1_validate_change() to allow more flexibility in setting cpus or mems in v2. cpuset_is_populated() needs to be moved into cpuset-internal.h as it is needed by the empty cpus/mems checking code. Also add a test case to test_cpuset_prs.sh to verify that. Reported-by: Chen Ridong <chenridong@huaweicloud.com> Closes: https://lore.kernel.org/lkml/7a3ec392-2e86-4693-aa9f-1e668a668b9c@huaweicloud.com/ Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2026-01-12cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflictWaiman Long
Currently, when setting a cpuset's cpuset.cpus to a value that conflicts with the cpuset.cpus/cpuset.cpus.exclusive of a sibling partition, the sibling's partition state becomes invalid. This is overly harsh and is probably not necessary. The cpuset.cpus.exclusive control file, if set, will override the cpuset.cpus of the same cpuset when creating a cpuset partition. So cpuset.cpus has less priority than cpuset.cpus.exclusive in setting up a partition. However, it cannot override a conflicting cpuset.cpus file in a sibling cpuset and the partition creation process will fail. This is inconsistent. That will also make using cpuset.cpus.exclusive less valuable as a tool to set up cpuset partitions as the users have to check if such a cpuset.cpus conflict exists or not. Fix these problems by making sure that once a cpuset.cpus.exclusive is set without failure, it will always be allowed to form a valid partition as long as at least one CPU can be granted from its parent irrespective of the state of the siblings' cpuset.cpus values. Of course, setting cpuset.cpus.exclusive will fail if it conflicts with the cpuset.cpus.exclusive or the cpuset.cpus.exclusive.effective value of a sibling. Partition can still be created by setting only cpuset.cpus without setting cpuset.cpus.exclusive. However, any conflicting CPUs in sibling's cpuset.cpus.exclusive.effective and cpuset.cpus.exclusive values will be removed from its cpuset.cpus.exclusive.effective as long as there is still one or more CPUs left and can be granted from its parent. This CPU stripping is currently done in rm_siblings_excl_cpus(). The new code will now try its best to enable the creation of new partitions with only cpuset.cpus set without invalidating existing ones. However it is not guaranteed that all the CPUs requested in cpuset.cpus will be used in the new partition even when all these CPUs can be granted from the parent. This is similar to the fact that cpuset.cpus.effective may not be able to include all the CPUs requested in cpuset.cpus. In this case, the parent may not able to grant all the exclusive CPUs requested in cpuset.cpus to cpuset.cpus.exclusive.effective if some of them have already been granted to other partitions earlier. With the creation of multiple sibling partitions by setting only cpuset.cpus, this does have the side effect that their exact cpuset.cpus.exclusive.effective settings will depend on the order of partition creation if there are conflicts. Due to the exclusive nature of the CPUs in a partition, it is not easy to make it fair other than the old behavior of invalidating all the conflicting partitions. For example, # echo "0-2" > A1/cpuset.cpus # echo "root" > A1/cpuset.cpus.partition # cat A1/cpuset.cpus.partition root # cat A1/cpuset.cpus.exclusive.effective 0-2 # echo "2-4" > B1/cpuset.cpus # echo "root" > B1/cpuset.cpus.partition # cat B1/cpuset.cpus.partition root # cat B1/cpuset.cpus.exclusive.effective 3-4 # cat B1/cpuset.cpus.effective 3-4 For users who want to be sure that they can get most of the CPUs they want, cpuset.cpus.exclusive should be used instead if they can set it successfully without failure. Setting cpuset.cpus.exclusive will guarantee that sibling conflicts from then onward is no longer possible. To make this change, we have to separate out the is_cpu_exclusive() check in cpus_excl_conflict() into a cgroup v1 only cpuset1_cpus_excl_conflict() helper. The cpus_allowed_validate_change() helper is now no longer needed and can be removed. Some existing tests in test_cpuset_prs.sh are updated and new ones are added to reflect the new behavior. The cgroup-v2.rst doc file is also updated the clarify what exclusive CPUs will be used when a partition is created. Reported-by: Sun Shaojie <sunshaojie@kylinos.cn> Closes: https://lore.kernel.org/lkml/20251117015708.977585-1-sunshaojie@kylinos.cn/ Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-08selftests: cgroup: Replace sleep with cg_read_key_long_poll() for waiting on ↵Guopeng Zhang
nr_dying_descendants Replace the manual sleep-and-retry logic in test_kmem_dead_cgroups() with the new helper `cg_read_key_long_poll()`. This change improves the robustness of the test by polling the "nr_dying_descendants" counter in `cgroup.stat` until it reaches 0 or the timeout is exceeded. Additionally, increase the retry timeout to 8 seconds (from 5 seconds) based on testing results: - With 5-second timeout: 4/20 runs passed. - With 8-second timeout: 20/20 runs passed. The 8 second timeout is based on stress testing of test_kmem_dead_cgroups() under load: 5 seconds was occasionally not enough for reclaim of dying descendants to complete, whereas 8 seconds consistently covered the observed latencies. This value is intended as a generous upper bound for the asynchronous reclaim and is not tied to any specific kernel constant, so it can be adjusted in the future if reclaim behavior changes. Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-08selftests: cgroup: make test_memcg_sock robust against delayed sock statsGuopeng Zhang
test_memcg_sock() currently requires that memory.stat's "sock " counter is exactly zero immediately after the TCP server exits. On a busy system this assumption is too strict: - Socket memory may be freed with a small delay (e.g. RCU callbacks). - memcg statistics are updated asynchronously via the rstat flushing worker, so the "sock " value in memory.stat can stay non-zero for a short period of time even after all socket memory has been uncharged. As a result, test_memcg_sock() can intermittently fail even though socket memory accounting is working correctly. Make the test more robust by polling memory.stat for the "sock " counter and allowing it some time to drop to zero instead of checking it only once. The timeout is set to 3 seconds to cover the periodic rstat flush interval (FLUSH_TIME = 2*HZ by default) plus some scheduling slack. If the counter does not become zero within the timeout, the test still fails as before. On my test system, running test_memcontrol 50 times produced: - Before this patch: 6/50 runs passed. - After this patch: 50/50 runs passed. Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn> Suggested-by: Lance Yang <lance.yang@linux.dev> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-08selftests: cgroup: Add cg_read_key_long_poll() to poll a cgroup key with retriesGuopeng Zhang
Introduce a new helper function `cg_read_key_long_poll()` in cgroup_util.h. This function polls the specified key in a cgroup file until it matches the expected value or the retry limit is reached, with configurable wait intervals between retries. This helper is particularly useful for handling asynchronously updated cgroup statistics (e.g., memory.stat), where immediate reads may observe stale values, especially on busy systems. It allows tests and other utilities to handle such cases more flexibly. Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn> Suggested-by: Michal Koutný <mkoutny@suse.com> Reviewed-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-12-06Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Pull non-MM updates from Andrew Morton: - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko) fixes a build issue and does some cleanup in ib/sys_info.c - "Implement mul_u64_u64_div_u64_roundup()" (David Laight) enhances the 64-bit math code on behalf of a PWM driver and beefs up the test module for these library functions - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich) makes BPF symbol names, sizes, and line numbers available to the GDB debugger - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang) adds a sysctl which can be used to cause additional info dumping when the hung-task and lockup detectors fire - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu) adds a general base64 encoder/decoder to lib/ and migrates several users away from their private implementations - "rbree: inline rb_first() and rb_last()" (Eric Dumazet) makes TCP a little faster - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin) reworks the KEXEC Handover interfaces in preparation for Live Update Orchestrator (LUO), and possibly for other future clients - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin) increases the flexibility of KEXEC Handover. Also preparation for LUO - "Live Update Orchestrator" (Pasha Tatashin) is a major new feature targeted at cloud environments. Quoting the cover letter: This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. Mike Rappaport merits a mention here, for his extensive review and testing work. - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain) moves the kexec and kdump sysfs entries from /sys/kernel/ to /sys/kernel/kexec/ and adds back-compatibility symlinks which can hopefully be removed one day - "kho: fixes for vmalloc restoration" (Mike Rapoport) fixes a BUG which was being hit during KHO restoration of vmalloc() regions * tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits) calibrate: update header inclusion Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()" vmcoreinfo: track and log recoverable hardware errors kho: fix restoring of contiguous ranges of order-0 pages kho: kho_restore_vmalloc: fix initialization of pages array MAINTAINERS: TPM DEVICE DRIVER: update the W-tag init: replace simple_strtoul with kstrtoul to improve lpj_setup KHO: fix boot failure due to kmemleak access to non-PRESENT pages Documentation/ABI: new kexec and kdump sysfs interface Documentation/ABI: mark old kexec sysfs deprecated kexec: move sysfs entries to /sys/kernel/kexec test_kho: always print restore status kho: free chunks using free_page() instead of kfree() selftests/liveupdate: add kexec test for multiple and empty sessions selftests/liveupdate: add simple kexec-based selftest for LUO selftests/liveupdate: add userspace API selftests docs: add documentation for memfd preservation via LUO mm: memfd_luo: allow preserving memfd liveupdate: luo_file: add private argument to store runtime state mm: shmem: export some functions to internal.h ...
2025-12-03Merge tag 'cgroup-for-6.19' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - Defer task cgroup unlink until after the dying task's final context switch so that controllers see the cgroup properly populated until the task is truly gone - cpuset cleanups and simplifications. Enforce that domain isolated CPUs stay in root or isolated partitions and fail if isolated+nohz_full would leave no housekeeping CPU. Fix sched/deadline root domain handling during CPU hot-unplug and race for tasks in attaching cpusets - Misc fixes including memory reclaim protection documentation and selftest KTAP conformance * tag 'cgroup-for-6.19' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (21 commits) cpuset: Treat cpusets in attaching as populated sched/deadline: Walk up cpuset hierarchy to decide root domain when hot-unplug cgroup/cpuset: Introduce cpuset_cpus_allowed_locked() docs: cgroup: No special handling of unpopulated memcgs docs: cgroup: Note about sibling relative reclaim protection docs: cgroup: Explain reclaim protection target selftests/cgroup: conform test to KTAP format output cpuset: remove need_rebuild_sched_domains cpuset: remove global remote_children list cpuset: simplify node setting on error cgroup: include missing header for struct irq_work cgroup: Fix sleeping from invalid context warning on PREEMPT_RT cgroup/cpuset: Globally track isolated_cpus update cgroup/cpuset: Ensure domain isolated CPUs stay in root or isolated partition cgroup/cpuset: Move up prstate_housekeeping_conflict() helper cgroup/cpuset: Fail if isolated and nohz_full don't leave any housekeeping cgroup/cpuset: Rename update_unbound_workqueue_cpumask() to update_isolation_cpumasks() cgroup: Defer task cgroup unlink until after the task is done switching out cgroup: Move dying_tasks cleanup from cgroup_task_release() to cgroup_task_free() cgroup: Rename cgroup lifecycle hooks to cgroup_task_*() ...
2025-11-27selftests: complete kselftest include centralizationBala-Vignesh-Reddy
This follow-up patch completes centralization of kselftest.h and ksefltest_harness.h includes in remaining seltests files, replacing all relative paths with a non-relative paths using shared -I include path in lib.mk Tested with gcc-13.3 and clang-18.1, and cross-compiled successfully on riscv, arm64, x86_64 and powerpc arch. [reddybalavignesh9979@gmail.com: add selftests include path for kselftest.h] Link: https://lkml.kernel.org/r/20251017090201.317521-1-reddybalavignesh9979@gmail.com Link: https://lkml.kernel.org/r/20251016104409.68985-1-reddybalavignesh9979@gmail.com Signed-off-by: Bala-Vignesh-Reddy <reddybalavignesh9979@gmail.com> Suggested-by: Andrew Morton <akpm@linux-foundation.org> Link: https://lore.kernel.org/lkml/20250820143954.33d95635e504e94df01930d0@linux-foundation.org/ Reviewed-by: Wei Yang <richard.weiyang@gmail.com> Cc: David Hildenbrand <david@redhat.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Günther Noack <gnoack@google.com> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Liam Howlett <liam.howlett@oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com> Cc: Michal Hocko <mhocko@suse.com> Cc: Mickael Salaun <mic@digikod.net> Cc: Ming Lei <ming.lei@redhat.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Shuah Khan <shuah@kernel.org> Cc: Simon Horman <horms@kernel.org> Cc: Suren Baghdasaryan <surenb@google.com> Cc: Vlastimil Babka <vbabka@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-14selftests/cgroup: conform test to KTAP format outputGuopeng Zhang
Conform the layout, informational and status messages to KTAP. No functional change is intended other than the layout of output messages. Signed-off-by: Guopeng Zhang <zhangguopeng@kylinos.cn> Suggested-by: Sebastian Chlad <sebastian.chlad@suse.com> Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-10-15selftests: cgroup: Use values_close_report in test_cpuSebastian Chlad
Convert test_cpu to use the newly added values_close_report() helper to print detailed diagnostics when a tolerance check fails. This provides clearer insight into deviations while run in the CI. Signed-off-by: Sebastian Chlad <sebastian.chlad@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-10-15selftests: cgroup: add values_close_report helperSebastian Chlad
Some cgroup selftests, such as test_cpu, occasionally fail by a very small margin and if run in the CI context, it is useful to have detailed diagnostic output to understand the deviation. Introduce a values_close_report() helper which performs the same comparison as values_close(), but prints detailed information when the values differ beyond the allowed tolerance. Signed-off-by: Sebastian Chlad <sebastian.chlad@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-08-27selftests: cgroup: Make test_pids backwards compatibleMichal Koutný
The predicates in test expect event counting from 73e75e6fc352b ("cgroup/pids: Separate semantics of pids.events related to pids.max") and the test would fail on older kernels. We want to have one version of tests for all, so detect the feature and skip the test on old kernels. (The test could even switch to check v1 semantics based on the flag but keep it simple for now.) Fixes: 9f34c566027b6 ("selftests: cgroup: Add basic tests for pids controller") Signed-off-by: Michal Koutný <mkoutny@suse.com> Tested-by: Sebastian Chlad <sebastian.chlad@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-08-22cgroup: selftests: Add tests for freezer timeTiffany Yang
Test cgroup v2 freezer time stat. Freezer time accounting should be independent of other cgroups in the hierarchy and should increase iff a cgroup is CGRP_FREEZE (regardless of whether it reaches CGRP_FROZEN). Skip these tests on systems without freeze time accounting. Signed-off-by: Tiffany Yang <ynaffit@google.com> Cc: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-07-17selftests/cgroup: fix cpu.max testsShashank Balaji
Current cpu.max tests (both the normal one and the nested one) are broken. They setup cpu.max with 1000 us quota and the default period (100,000 us). A cpu hog is run for a duration of 1s as per wall clock time. This corresponds to 10 periods, hence an expected usage of 10,000 us. We want the measured usage (as per cpu.stat) to be close to 10,000 us. Previously, this approximate equality test was done by `!values_close(usage_usec, expected_usage_usec, 95)`: if the absolute difference between usage_usec and expected_usage_usec is greater than 95% of their sum, then we pass. And expected_usage_usec was set to 1,000,000 us. Mathematically, this translates to the following being true for pass: |usage - expected_usage| > (usage + expected_usage)*0.95 If usage > expected_usage: usage - expected_usage > (usage + expected_usage)*0.95 0.05*usage > 1.95*expected_usage usage > 39*expected_usage = 39s If usage < expected_usage: expected_usage - usage > (usage + expected_usage)*0.95 0.05*expected_usage > 1.95*usage usage < 0.0256*expected_usage = 25,600 us Combined, Pass if usage < 25,600 us or > 39 s, which makes no sense given that all we need is for usage_usec to be close to 10,000 us. Fix this by explicitly calcuating the expected usage duration based on the configured quota, default period, and the duration, and compare usage_usec and expected_usage_usec using values_close() with a 10% error margin. Also, use snprintf to get the quota string to write to cpu.max instead of hardcoding the quota, ensuring a single source of truth. Remove the check comparing user_usec and expected_usage_usec, since on running this test modified with printfs, it's seen that user_usec and usage_usec can regularly exceed the theoretical expected_usage_usec: $ sudo ./test_cpu user: 10485, usage: 10485, expected: 10000 ok 1 test_cpucg_max user: 11127, usage: 11127, expected: 10000 ok 2 test_cpucg_max_nested $ sudo ./test_cpu user: 10286, usage: 10286, expected: 10000 ok 1 test_cpucg_max user: 10404, usage: 11271, expected: 10000 ok 2 test_cpucg_max_nested Hence, a values_close() check of usage_usec and expected_usage_usec is sufficient. Fixes: a79906570f9646ae17 ("cgroup: Add test_cpucg_max_nested() testcase") Fixes: 889ab8113ef1386c57 ("cgroup: Add test_cpucg_max() testcase") Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Shashank Balaji <shashank.mahadasyam@sony.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-07-12selftests: cgroup: Fix missing newline in test_zswap_writeback_oneSebastian Chlad
Fixes malformed test output due to missing newline Signed-off-by: Sebastian Chlad <sebastian.chlad@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-07-12selftests: cgroup: Allow longer timeout for kmem_dead_cgroups cleanupSebastian Chlad
The test_kmem_dead_cgroups test currently assumes that RCU and memory reclaim will complete within 5 seconds. In some environments this timeout may be insufficient, leading to spurious test failures. This patch introduces max_time set to 20 which is then used in the test. After 5th sec the debug message is printed to indicate the cleanup is still ongoing. In the system under test with 16 CPUs the original test was failing most of the time and the cleanup time took usually approx. 6sec. Further tests were conducted with and without do_rcu_barrier and the results (respectively) are as follow: quantiles 0 0.25 0.5 0.75 1 1 2 3 8 20 (mean = 4.7667) 3 5 8 8 20 (mean = 7.6667) Acked-by: Michal Koutny <mkoutny@suse.com> Signed-off-by: Sebastian Chlad <sebastian.chlad@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-06-17selftests: cgroup: Fix compilation on pre-cgroupns kernelsMichal Koutný
The test would be skipped because of nsdelegate, so the defined value is not used (0 is always acceptable). Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-06-17selftests: cgroup: Optionally set up v1 environmentMichal Koutný
Use the missing mount of the unifier hierarchy as a hint of legacy system and prepare our own named v1 hierarchy for tests. The code is only in test_core.c and not cgroup_util.c because other selftests are related to controllers which will be exposed on v2 hierarchy but named hierarchies are only v1 thing. Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-06-17selftests: cgroup: Add support for named v1 hierarchies in test_coreMichal Koutný
This comes useful when using selftests from mainline on older kernels/setups that still rely on cgroup v1. The core tests that rely on v2 specific features are skipped, the remaining ones are adjusted to work with a v1 hierarchy. The expected output on v1 system: ok 1 # SKIP test_cgcore_internal_process_constraint ok 2 # SKIP test_cgcore_top_down_constraint_enable ok 3 # SKIP test_cgcore_top_down_constraint_disable ok 4 # SKIP test_cgcore_no_internal_process_constraint_on_threads ok 5 # SKIP test_cgcore_parent_becomes_threaded ok 6 # SKIP test_cgcore_invalid_domain ok 7 # SKIP test_cgcore_populated ok 8 test_cgcore_proc_migration ok 9 test_cgcore_thread_migration ok 10 test_cgcore_destroy ok 11 test_cgcore_lesser_euid_open ok 12 # SKIP test_cgcore_lesser_ns_open Signed-off-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>