linux/tools/testing/selftests/cgroup, branch master

Merge tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2026-04-15T19:59:16Z

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 ...

Merge tag 'driver-core-7.1-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/driver-core/driver-core

2026-04-14T02:03:11Z

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 - 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 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) { 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) { if bar.read(WATER).rx_above_watermark() { // drain the FIFO } } fn set_parity(bar: &pci::Bar, 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 ...

selftest: memcg: skip memcg_sock test if address family not supported

2026-04-05T20:53:27Z

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 Acked-by: Michal Koutný Acked-by: Shakeel Butt Cc: Johannes Weiner Cc: Michal Hocko Cc: Michal Koutný Cc: Mike Rapoport Cc: Muchun Song Cc: Roman Gushchin Cc: Shuah Khan Cc: Tejun Heo Signed-off-by: Andrew Morton

selftests/cgroup: add test for zswap incompressible pages

2026-04-05T20:53:00Z

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 Acked-by: Shakeel Butt Acked-by: Nhat Pham Reviewed-by: SeongJae Park Cc: Chengming Zhou Cc: Johannes Weiner Cc: Jonathan Corbet Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Roman Gushchin Cc: Shuah Khan Cc: Tejun Heo Cc: Yosry Ahmed Signed-off-by: Andrew Morton

selftests/cgroup: Don't require synchronous populated update on task exit

2026-03-24T20:21:57Z

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 Signed-off-by: Tejun Heo Tested-by: Sebastian Andrzej Siewior Cc: Christian Brauner Cc: cgroups@vger.kernel.org

selftests: memcg: Add tests for IN_DELETE_SELF and IN_IGNORED

2026-03-12T14:51:03Z

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 Acked-by: Tejun Heo Acked-by: Amir Goldstein Tested-by: syzbot@syzkaller.appspotmail.com Link: https://patch.msgid.link/20260225223404.783173-4-tjmercier@google.com Signed-off-by: Greg Kroah-Hartman

cgroup/cpuset: Defer housekeeping_update() calls from CPU hotplug to workqueue

2026-02-23T20:42:11Z

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 Signed-off-by: Tejun Heo

kselftest/cgroup: Simplify test_cpuset_prs.sh by removing "S+" command

2026-02-23T20:42:05Z

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 Signed-off-by: Tejun Heo

cgroup/cpuset: Move the v1 empty cpus/mems check to cpuset1_validate_change()

2026-01-12T19:03:22Z

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 Closes: https://lore.kernel.org/lkml/7a3ec392-2e86-4693-aa9f-1e668a668b9c@huaweicloud.com/ Signed-off-by: Waiman Long Reviewed-by: Chen Ridong Signed-off-by: Tejun Heo

cgroup/cpuset: Don't invalidate sibling partitions on cpuset.cpus conflict

2026-01-12T19:02:46Z

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 Closes: https://lore.kernel.org/lkml/20251117015708.977585-1-sunshaojie@kylinos.cn/ Signed-off-by: Waiman Long Reviewed-by: Chen Ridong Signed-off-by: Tejun Heo