summaryrefslogtreecommitdiffstats
path: root/kernel/cgroup
AgeCommit message (Collapse)AuthorLines
2025-11-20cgroup/cpuset: Introduce cpuset_cpus_allowed_locked()Pingfan Liu-15/+36
cpuset_cpus_allowed() uses a reader lock that is sleepable under RT, which means it cannot be called inside raw_spin_lock_t context. Introduce a new cpuset_cpus_allowed_locked() helper that performs the same function as cpuset_cpus_allowed() except that the caller must have acquired the cpuset_mutex so that no further locking will be needed. Suggested-by: Waiman Long <longman@redhat.com> Signed-off-by: Pingfan Liu <piliu@redhat.com> Cc: Waiman Long <longman@redhat.com> Cc: Tejun Heo <tj@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Koutný <mkoutny@suse.com> Cc: linux-kernel@vger.kernel.org To: cgroups@vger.kernel.org Reviewed-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-17Merge back earlier material related to system sleep for 6.19Rafael J. Wysocki-1/+1
2025-11-16memcg: net: track network throttling due to memcg memory pressureShakeel Butt-0/+1
The kernel can throttle network sockets if the memory cgroup associated with the corresponding socket is under memory pressure. The throttling actions include clamping the transmit window, failing to expand receive or send buffers, aggressively prune out-of-order receive queue, FIN deferred to a retransmitted packet and more. Let's add memcg metric to track such throttling actions. At the moment memcg memory pressure is defined through vmpressure and in future it may be defined using PSI or we may add more flexible way for the users to define memory pressure, maybe through ebpf. However the potential throttling actions will remain the same, so this newly introduced metric will continue to track throttling actions irrespective of how memcg memory pressure is defined. Link: https://lkml.kernel.org/r/20251016161035.86161-1-shakeel.butt@linux.dev Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev> Acked-by: Roman Gushchin <roman.gushchin@linux.dev> Reviewed-by: Kuniyuki Iwashima <kuniyu@google.com> Reviewed-by: Daniel Sedlak <daniel.sedlak@cdn77.com> Cc: David S. Miller <davem@davemloft.net> Cc: Eric Dumazet <edumazet@google.com> Cc: Jakub Kacinski <kuba@kernel.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Michal Hocko <mhocko@kernel.org> Cc: Muchun Song <muchun.song@linux.dev> Cc: Neal Cardwell <ncardwell@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Simon Horman <horms@kernel.org> Cc: Tejun Heo <tj@kernel.org> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2025-11-11cpuset: remove need_rebuild_sched_domainsChen Ridong-5/+1
Previously, update_cpumasks_hier() used need_rebuild_sched_domains to decide whether to invoke rebuild_sched_domains_locked(). Now that rebuild_sched_domains_locked() only sets force_rebuild, the flag is redundant. Hence, remove it. Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-11cpuset: remove global remote_children listChen Ridong-12/+11
The remote_children list is used to track all remote partitions attached to a cpuset. However, it serves no other purpose. Using a boolean flag to indicate whether a cpuset is a remote partition is a more direct approach, making remote_children unnecessary. This patch replaces the list with a remote_partition flag in the cpuset structure and removes remote_children entirely. Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-11cpuset: simplify node setting on errorChen Ridong-12/+9
There is no need to jump to the 'done' label upon failure, as no cleanup is required. Return the error code directly instead. Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Reviewed-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-11cgroup: include missing header for struct irq_workBert Karwatzki-0/+1
To compile cgroup.c with PREEMPT_RT=y include header which declares struct irq_work. Fixes: 9311e6c29b34 ("cgroup: Fix sleeping from invalid context warning on PREEMPT_RT") Signed-off-by: Bert Karwatzki <spasswolf@web.de> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-11ns: drop custom reference count initialization for initial namespacesChristian Brauner-1/+1
Initial namespaces don't modify their reference count anymore. They remain fixed at one so drop the custom refcount initializations. Link: https://patch.msgid.link/20251110-work-namespace-nstree-fixes-v1-16-e8a9264e0fb9@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-11Merge branch 'kbuild-6.19.fms.extension'Christian Brauner-1/+1
Bring in the shared branch with the kbuild tree to enable '-fms-extensions' for 6.19. Further namespace cleanup work requires this extension. Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-06cgroup: Fix sleeping from invalid context warning on PREEMPT_RTTejun Heo-1/+54
cgroup_task_dead() is called from finish_task_switch() which runs with preemption disabled and doesn't allow scheduling even on PREEMPT_RT. The function needs to acquire css_set_lock which is a regular spinlock that can sleep on RT kernels, leading to "sleeping function called from invalid context" warnings. css_set_lock is too large in scope to convert to a raw_spinlock. However, the unlinking operations don't need to run synchronously - they just need to complete after the task is done running. On PREEMPT_RT, defer the work through irq_work. While the work doesn't need to happen immediately, it can't be delayed indefinitely either as the dead task pins the cgroup and task_struct can be pinned indefinitely. Use the lazy version of irq_work to allow batching and lower impact while ensuring timely completion. v2: Use IRQ_WORK_INIT_LAZY instead of immediate irq_work and add explanation for why the work can't be delayed indefinitely (Sebastian Andrzej Siewior). Fixes: d245698d727a ("cgroup: Defer task cgroup unlink until after the task is done switching out") Reported-by: Calvin Owens <calvin@wbinvd.org> Link: https://lore.kernel.org/r/20251104181114.489391-1-calvin@wbinvd.org Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-05cgroup/cpuset: Globally track isolated_cpus updateWaiman Long-38/+35
The current cpuset code passes a local isolcpus_updated flag around in a number of functions to determine if external isolation related cpumasks like wq_unbound_cpumask should be updated. It is a bit cumbersome and makes the code more complex. Simplify the code by using a global boolean flag "isolated_cpus_updating" to track this. This flag will be set in isolated_cpus_update() and cleared in update_isolation_cpumasks(). No functional change is expected. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-05cgroup/cpuset: Ensure domain isolated CPUs stay in root or isolated partitionWaiman Long-4/+6
Commit 4a74e418881f ("cgroup/cpuset: Check partition conflict with housekeeping setup") is supposed to ensure that domain isolated CPUs designated by the "isolcpus" boot command line option stay either in root partition or in isolated partitions. However, the required check wasn't implemented when a remote partition was created or when an existing partition changed type from "root" to "isolated". Even though this is a relatively minor issue, we still need to add the required prstate_housekeeping_conflict() call in the right places to ensure that the rule is strictly followed. The following steps can be used to reproduce the problem before this fix. # fmt -1 /proc/cmdline | grep isolcpus isolcpus=9 # cd /sys/fs/cgroup/ # echo +cpuset > cgroup.subtree_control # mkdir test # echo 9 > test/cpuset.cpus # echo isolated > test/cpuset.cpus.partition # cat test/cpuset.cpus.partition isolated # cat test/cpuset.cpus.effective 9 # echo root > test/cpuset.cpus.partition # cat test/cpuset.cpus.effective 9 # cat test/cpuset.cpus.partition root With this fix, the last few steps will become: # echo root > test/cpuset.cpus.partition # cat test/cpuset.cpus.effective 0-8,10-95 # cat test/cpuset.cpus.partition root invalid (partition config conflicts with housekeeping setup) Reported-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-05cgroup/cpuset: Move up prstate_housekeeping_conflict() helperWaiman Long-20/+20
Move up the prstate_housekeeping_conflict() helper so that it can be used in remote partition code. Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-05cgroup/cpuset: Fail if isolated and nohz_full don't leave any housekeepingWaiman Long-1/+73
Currently the user can set up isolated cpus via cpuset and nohz_full in such a way that leaves no housekeeping CPU (i.e. no CPU that is neither domain isolated nor nohz full). This can be a problem for other subsystems (e.g. the timer wheel imgration). Prevent this configuration by blocking any assignation that would cause the union of domain isolated cpus and nohz_full to covers all CPUs. [longman: Remove isolated_cpus_should_update() and rewrite the checking in update_prstate() and update_parent_effective_cpumask()] Originally-by: Gabriele Monaco <gmonaco@redhat.com> Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-05cgroup/cpuset: Rename update_unbound_workqueue_cpumask() to ↵Gabriele Monaco-6/+6
update_isolation_cpumasks() update_unbound_workqueue_cpumask() updates unbound workqueues settings when there's a change in isolated CPUs, but it can be used for other subsystems requiring updated when isolated CPUs change. Generalise the name to update_isolation_cpumasks() to prepare for other functions unrelated to workqueues to be called in that spot. [longman: Change the function name to update_isolation_cpumasks()] Acked-by: Frederic Weisbecker <frederic@kernel.org> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Gabriele Monaco <gmonaco@redhat.com> Signed-off-by: Waiman Long <longman@redhat.com> Reviewed-by: Chen Ridong <chenridong@huaweicloud.com> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-04cgroup: use credential guards in cgroup_attach_permissions()Christian Brauner-6/+4
Use credential guards for scoped credential override with automatic restoration on scope exit. Link: https://patch.msgid.link/20251103-work-creds-guards-simple-v1-15-a3e156839e7f@kernel.org Reviewed-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-03cgroup: Defer task cgroup unlink until after the task is done switching outTejun Heo-9/+14
When a task exits, css_set_move_task(tsk, cset, NULL, false) unlinks the task from its cgroup. From the cgroup's perspective, the task is now gone. If this makes the cgroup empty, it can be removed, triggering ->css_offline() callbacks that notify controllers the cgroup is going offline resource-wise. However, the exiting task can still run, perform memory operations, and schedule until the final context switch in finish_task_switch(). This creates a confusing situation where controllers are told a cgroup is offline while resource activities are still happening in it. While this hasn't broken existing controllers, it has caused direct confusion for sched_ext schedulers. Split cgroup_task_exit() into two functions. cgroup_task_exit() now only calls the subsystem exit callbacks and continues to be called from do_exit(). The css_set cleanup is moved to the new cgroup_task_dead() which is called from finish_task_switch() after the final context switch, so that the cgroup only appears empty after the task is truly done running. This also reorders operations so that subsys->exit() is now called before unlinking from the cgroup, which shouldn't break anything. Cc: Dan Schatzberg <dschatzberg@meta.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-03cgroup: Move dying_tasks cleanup from cgroup_task_release() to ↵Tejun Heo-4/+5
cgroup_task_free() Currently, cgroup_task_exit() adds thread group leaders with live member threads to their css_set's dying_tasks list (so cgroup.procs iteration can still see the leader), and cgroup_task_release() later removes them with list_del_init(&task->cg_list). An upcoming patch will defer the dying_tasks list addition, moving it from cgroup_task_exit() (called from do_exit()) to a new function called from finish_task_switch(). However, release_task() (which calls cgroup_task_release()) can run either before or after finish_task_switch(), creating a race where cgroup_task_release() might try to remove the task from dying_tasks before or while it's being added. Move the list_del_init() from cgroup_task_release() to cgroup_task_free() to fix this race. cgroup_task_free() runs from __put_task_struct(), which is always after both paths, making the cleanup safe. Cc: Dan Schatzberg <dschatzberg@meta.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-03cgroup: Rename cgroup lifecycle hooks to cgroup_task_*()Tejun Heo-5/+6
The current names cgroup_exit(), cgroup_release(), and cgroup_free() are confusing because they look like they're operating on cgroups themselves when they're actually task lifecycle hooks. For example, cgroup_init() initializes the cgroup subsystem while cgroup_exit() is a task exit notification to cgroup. Rename them to cgroup_task_exit(), cgroup_task_release(), and cgroup_task_free() to make it clear that these operate on tasks. Cc: Dan Schatzberg <dschatzberg@meta.com> Cc: Peter Zijlstra <peterz@infradead.org> Reviewed-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-11-03ns: rename to exit_nsproxy_namespaces()Christian Brauner-3/+3
The current naming is very misleading as this really isn't exiting all of the task's namespaces. It is only exiting the namespaces that hang of off nsproxy. Reflect that in the name. Link: https://patch.msgid.link/20251029-work-namespace-nstree-listns-v4-10-2e6f823ebdc0@kernel.org Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-11-03ns: use NS_COMMON_INIT() for all namespacesChristian Brauner-4/+1
Now that we have a common initializer use it for all static namespaces. Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-31cgroup: add cgroup namespace to tree after owner is setChristian Brauner-1/+1
Otherwise we trip VFS_WARN_ON_ONC() in __ns_tree_add_raw(). Link: https://patch.msgid.link/20251029-work-namespace-nstree-listns-v4-6-2e6f823ebdc0@kernel.org Fixes: 7c6059398533 ("cgroup: support ns lookup") Tested-by: syzbot@syzkaller.appspotmail.com Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-10-30freezer: Clarify that only cgroup1 freezer uses PM freezerTejun Heo-1/+1
cgroup1 freezer piggybacks on the PM freezer, which inadvertently allowed userspace to produce uninterruptible tasks at will. To avoid the issue, cgroup2 freezer switched to a separate job control based mechanism. While this happened a long time ago, the code and comment haven't been updated making it confusing to people who aren't familiar with the history. Rename cgroup_freezing() to cgroup1_freezing() and update comments on top of freezing() and frozen() to clarify that cgroup2 freezer isn't covered by the PM freezer mechanism. Signed-off-by: Tejun Heo <tj@kernel.org> Suggested-by: Qu Wenruo <wqu@suse.com> Link: https://patch.msgid.link/aPZ3q6Hm865NicBC@slm.duckdns.org Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2025-10-29Merge branch 'linus/master' into sched/core, to resolve conflictPeter Zijlstra-1/+1
Conflicts: kernel/sched/ext.c Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org>
2025-10-20Merge tag 'cgroup-for-6.18-rc2-fixes' of ↵Linus Torvalds-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fixes from Tejun Heo: - Fix seqcount lockdep assertion failure in cgroup freezer on PREEMPT_RT. Plain seqcount_t expects preemption disabled, but PREEMPT_RT spinlocks don't disable preemption. Switch to seqcount_spinlock_t to properly associate css_set_lock with the freeze timing seqcount. - Misc changes including kernel-doc warning fix for misc_res_type enum and improved selftest diagnostics. * tag 'cgroup-for-6.18-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup/misc: fix misc_res_type kernel-doc warning selftests: cgroup: Use values_close_report in test_cpu selftests: cgroup: add values_close_report helper cgroup: Fix seqcount lockdep assertion in cgroup freezer
2025-10-20cgroup/cpuset: Don't track # of local child partitionsWaiman Long-31/+13
The cpuset structure has a nr_subparts field which tracks the number of child local partitions underneath a particular cpuset. Right now, nr_subparts is only used in partition_is_populated() to avoid iteration of child cpusets if the condition is right. So by always performing the child iteration, we can avoid tracking the number of child partitions and simplify the code a bit. Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-10-16sched: Rename do_set_cpus_allowed()Peter Zijlstra-1/+1
Hopefully saner naming. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Juri Lelli <juri.lelli@redhat.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
2025-10-04Merge tag 'rcu.2025.09.26a' of ↵Linus Torvalds-0/+1
git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux Pull RCU updates from Paul McKenney: "Documentation updates: - Update whatisRCU.rst and checklist.rst for recent RCU API additions - Fix RCU documentation formatting and typos - Replace dead Ottawa Linux Symposium links in RTFP.txt Miscellaneous RCU updates: - Document that rcu_barrier() hurries RCU_LAZY callbacks - Remove redundant interrupt disabling from rcu_preempt_deferred_qs_handler() - Move list_for_each_rcu from list.h to rculist.h, and adjust the include directive in kernel/cgroup/dmem.c accordingly - Make initial set of changes to accommodate upcoming system_percpu_wq changes SRCU updates: - Create an srcu_read_lock_fast_notrace() for eventual use in tracing, including adding guards - Document the reliance on per-CPU operations as implicit RCU readers in __srcu_read_{,un}lock_fast() - Document the srcu_flip() function's memory-barrier D's relationship to SRCU-fast readers - Remove a redundant preempt_disable() and preempt_enable() pair from srcu_gp_start_if_needed() Torture-test updates: - Fix jitter.sh spin time so that it actually varies as advertised. It is still quite coarse-grained, but at least it does now vary - Update torture.sh help text to include the not-so-new --do-normal parameter, which permits (for example) testing KCSAN kernels without doing non-debug kernels - Fix a number of false-positive diagnostics that were being triggered by rcutorture starting before boot completed. Running multiple near-CPU-bound rcutorture processes when there is only the boot CPU is after all a bit excessive - Substitute kcalloc() for kzalloc() - Remove a redundant kfree() and NULL out kfree()ed objects" * tag 'rcu.2025.09.26a' of git://git.kernel.org/pub/scm/linux/kernel/git/rcu/linux: (31 commits) rcu: WQ_UNBOUND added to sync_wq workqueue rcu: WQ_PERCPU added to alloc_workqueue users rcu: replace use of system_wq with system_percpu_wq refperf: Set reader_tasks to NULL after kfree() refperf: Remove redundant kfree() after torture_stop_kthread() srcu/tiny: Remove preempt_disable/enable() in srcu_gp_start_if_needed() srcu: Document srcu_flip() memory-barrier D relation to SRCU-fast srcu: Document __srcu_read_{,un}lock_fast() implicit RCU readers rculist: move list_for_each_rcu() to where it belongs refscale: Use kcalloc() instead of kzalloc() rcutorture: Use kcalloc() instead of kzalloc() docs: rcu: Replace multiple dead OLS links in RTFP.txt doc: Fix typo in RCU's torture.rst documentation Documentation: RCU: Retitle toctree index Documentation: RCU: Reduce toctree depth Documentation: RCU: Wrap kvm-remote.sh rerun snippet in literal code block rcu: docs: Requirements.rst: Abide by conventions of kernel documentation doc: Add RCU guards to checklist.rst doc: Update whatisRCU.rst for recent RCU API additions rcutorture: Delay forward-progress testing until boot completes ...
2025-10-03cgroup: Fix seqcount lockdep assertion in cgroup freezerNirbhay Sharma-1/+1
The commit afa3701c0e45 ("cgroup: cgroup.stat.local time accounting") introduced a seqcount to track freeze timing but initialized it as a plain seqcount_t using seqcount_init(). However, the write-side critical section in cgroup_do_freeze() holds the css_set_lock spinlock while calling write_seqcount_begin(). On PREEMPT_RT kernels, spinlocks do not disable preemption, causing the lockdep assertion for a plain seqcount_t, which checks for preemption being disabled, to fail. This triggers the following warning: WARNING: CPU: 0 PID: 9692 at include/linux/seqlock.h:221 Fix this by changing the type to seqcount_spinlock_t and initializing it with seqcount_spinlock_init() to associate css_set_lock with the seqcount. This allows lockdep to correctly validate that the spinlock is held during write operations, resolving the assertion failure on all kernel configurations. Reported-by: syzbot+27a2519eb4dad86d0156@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=27a2519eb4dad86d0156 Fixes: afa3701c0e45 ("cgroup: cgroup.stat.local time accounting") Signed-off-by: Nirbhay Sharma <nirbhay.lkd@gmail.com> Link: https://lore.kernel.org/r/20251002165510.KtY3IT--@linutronix.de/ Acked-by: Michal Koutný <mkoutny@suse.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-30Merge tag 'bpf-next-6.18' of ↵Linus Torvalds-4/+20
git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next Pull bpf updates from Alexei Starovoitov: - Support pulling non-linear xdp data with bpf_xdp_pull_data() kfunc (Amery Hung) Applied as a stable branch in bpf-next and net-next trees. - Support reading skb metadata via bpf_dynptr (Jakub Sitnicki) Also a stable branch in bpf-next and net-next trees. - Enforce expected_attach_type for tailcall compatibility (Daniel Borkmann) - Replace path-sensitive with path-insensitive live stack analysis in the verifier (Eduard Zingerman) This is a significant change in the verification logic. More details, motivation, long term plans are in the cover letter/merge commit. - Support signed BPF programs (KP Singh) This is another major feature that took years to materialize. Algorithm details are in the cover letter/marge commit - Add support for may_goto instruction to s390 JIT (Ilya Leoshkevich) - Add support for may_goto instruction to arm64 JIT (Puranjay Mohan) - Fix USDT SIB argument handling in libbpf (Jiawei Zhao) - Allow uprobe-bpf program to change context registers (Jiri Olsa) - Support signed loads from BPF arena (Kumar Kartikeya Dwivedi and Puranjay Mohan) - Allow access to union arguments in tracing programs (Leon Hwang) - Optimize rcu_read_lock() + migrate_disable() combination where it's used in BPF subsystem (Menglong Dong) - Introduce bpf_task_work_schedule*() kfuncs to schedule deferred execution of BPF callback in the context of a specific task using the kernel’s task_work infrastructure (Mykyta Yatsenko) - Enforce RCU protection for KF_RCU_PROTECTED kfuncs (Kumar Kartikeya Dwivedi) - Add stress test for rqspinlock in NMI (Kumar Kartikeya Dwivedi) - Improve the precision of tnum multiplier verifier operation (Nandakumar Edamana) - Use tnums to improve is_branch_taken() logic (Paul Chaignon) - Add support for atomic operations in arena in riscv JIT (Pu Lehui) - Report arena faults to BPF error stream (Puranjay Mohan) - Search for tracefs at /sys/kernel/tracing first in bpftool (Quentin Monnet) - Add bpf_strcasecmp() kfunc (Rong Tao) - Support lookup_and_delete_elem command in BPF_MAP_STACK_TRACE (Tao Chen) * tag 'bpf-next-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (197 commits) libbpf: Replace AF_ALG with open coded SHA-256 selftests/bpf: Add stress test for rqspinlock in NMI selftests/bpf: Add test case for different expected_attach_type bpf: Enforce expected_attach_type for tailcall compatibility bpftool: Remove duplicate string.h header bpf: Remove duplicate crypto/sha2.h header libbpf: Fix error when st-prefix_ops and ops from differ btf selftests/bpf: Test changing packet data from kfunc selftests/bpf: Add stacktrace map lookup_and_delete_elem test case selftests/bpf: Refactor stacktrace_map case with skeleton bpf: Add lookup_and_delete_elem for BPF_MAP_STACK_TRACE selftests/bpf: Fix flaky bpf_cookie selftest selftests/bpf: Test changing packet data from global functions with a kfunc bpf: Emit struct bpf_xdp_sock type in vmlinux BTF selftests/bpf: Task_work selftest cleanup fixes MAINTAINERS: Delete inactive maintainers from AF_XDP bpf: Mark kfuncs as __noclone selftests/bpf: Add kprobe multi write ctx attach test selftests/bpf: Add kprobe write ctx attach test selftests/bpf: Add uprobe context ip register change test ...
2025-09-30Merge tag 'cgroup-for-6.18' of ↵Linus Torvalds-427/+591
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: - Extensive cpuset code cleanup and refactoring work with no functional changes: CPU mask computation logic refactoring, introducing new helpers, removing redundant code paths, and improving error handling for better maintainability. - A few bug fixes to cpuset including fixes for partition creation failures when isolcpus is in use, missing error returns, and null pointer access prevention in free_tmpmasks(). - Core cgroup changes include replacing the global percpu_rwsem with per-threadgroup rwsem when writing to cgroup.procs for better scalability, workqueue conversions to use WQ_PERCPU and system_percpu_wq to prepare for workqueue default switching from percpu to unbound, and removal of unused code including the post_attach callback. - New cgroup.stat.local time accounting feature that tracks frozen time duration. - Misc changes including selftests updates (new freezer time tests and backward compatibility fixes), documentation sync, string function safety improvements, and 64-bit division fixes. * tag 'cgroup-for-6.18' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (39 commits) cpuset: remove is_prs_invalid helper cpuset: remove impossible warning in update_parent_effective_cpumask cpuset: remove redundant special case for null input in node mask update cpuset: fix missing error return in update_cpumask cpuset: Use new excpus for nocpu error check when enabling root partition cpuset: fix failure to enable isolated partition when containing isolcpus Documentation: cgroup-v2: Sync manual toctree cpuset: use partition_cpus_change for setting exclusive cpus cpuset: use parse_cpulist for setting cpus.exclusive cpuset: introduce partition_cpus_change cpuset: refactor cpus_allowed_validate_change cpuset: refactor out validate_partition cpuset: introduce cpus_excl_conflict and mems_excl_conflict helpers cpuset: refactor CPU mask buffer parsing logic cpuset: Refactor exclusive CPU mask computation logic cpuset: change return type of is_partition_[in]valid to bool cpuset: remove unused assignment to trialcs->partition_root_state cpuset: move the root cpuset write check earlier cgroup/cpuset: Remove redundant rcu_read_lock/unlock() in spin_lock cgroup: Remove redundant rcu_read_lock/unlock() in spin_lock ...
2025-09-29Merge tag 'namespace-6.18-rc1' of ↵Linus Torvalds-19/+15
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull namespace updates from Christian Brauner: "This contains a larger set of changes around the generic namespace infrastructure of the kernel. Each specific namespace type (net, cgroup, mnt, ...) embedds a struct ns_common which carries the reference count of the namespace and so on. We open-coded and cargo-culted so many quirks for each namespace type that it just wasn't scalable anymore. So given there's a bunch of new changes coming in that area I've started cleaning all of this up. The core change is to make it possible to correctly initialize every namespace uniformly and derive the correct initialization settings from the type of the namespace such as namespace operations, namespace type and so on. This leaves the new ns_common_init() function with a single parameter which is the specific namespace type which derives the correct parameters statically. This also means the compiler will yell as soon as someone does something remotely fishy. The ns_common_init() addition also allows us to remove ns_alloc_inum() and drops any special-casing of the initial network namespace in the network namespace initialization code that Linus complained about. Another part is reworking the reference counting. The reference counting was open-coded and copy-pasted for each namespace type even though they all followed the same rules. This also removes all open accesses to the reference count and makes it private and only uses a very small set of dedicated helpers to manipulate them just like we do for e.g., files. In addition this generalizes the mount namespace iteration infrastructure introduced a few cycles ago. As reminder, the vfs makes it possible to iterate sequentially and bidirectionally through all mount namespaces on the system or all mount namespaces that the caller holds privilege over. This allow userspace to iterate over all mounts in all mount namespaces using the listmount() and statmount() system call. Each mount namespace has a unique identifier for the lifetime of the systems that is exposed to userspace. The network namespace also has a unique identifier working exactly the same way. This extends the concept to all other namespace types. The new nstree type makes it possible to lookup namespaces purely by their identifier and to walk the namespace list sequentially and bidirectionally for all namespace types, allowing userspace to iterate through all namespaces. Looking up namespaces in the namespace tree works completely locklessly. This also means we can move the mount namespace onto the generic infrastructure and remove a bunch of code and members from struct mnt_namespace itself. There's a bunch of stuff coming on top of this in the future but for now this uses the generic namespace tree to extend a concept introduced first for pidfs a few cycles ago. For a while now we have supported pidfs file handles for pidfds. This has proven to be very useful. This extends the concept to cover namespaces as well. It is possible to encode and decode namespace file handles using the common name_to_handle_at() and open_by_handle_at() apis. As with pidfs file handles, namespace file handles are exhaustive, meaning it is not required to actually hold a reference to nsfs in able to decode aka open_by_handle_at() a namespace file handle. Instead the FD_NSFS_ROOT constant can be passed which will let the kernel grab a reference to the root of nsfs internally and thus decode the file handle. Namespaces file descriptors can already be derived from pidfds which means they aren't subject to overmount protection bugs. IOW, it's irrelevant if the caller would not have access to an appropriate /proc/<pid>/ns/ directory as they could always just derive the namespace based on a pidfd already. It has the same advantage as pidfds. It's possible to reliably and for the lifetime of the system refer to a namespace without pinning any resources and to compare them trivially. Permission checking is kept simple. If the caller is located in the namespace the file handle refers to they are able to open it otherwise they must hold privilege over the owning namespace of the relevant namespace. The namespace file handle layout is exposed as uapi and has a stable and extensible format. For now it simply contains the namespace identifier, the namespace type, and the inode number. The stable format means that userspace may construct its own namespace file handles without going through name_to_handle_at() as they are already allowed for pidfs and cgroup file handles" * tag 'namespace-6.18-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: (65 commits) ns: drop assert ns: move ns type into struct ns_common nstree: make struct ns_tree private ns: add ns_debug() ns: simplify ns_common_init() further cgroup: add missing ns_common include ns: use inode initializer for initial namespaces selftests/namespaces: verify initial namespace inode numbers ns: rename to __ns_ref nsfs: port to ns_ref_*() helpers net: port to ns_ref_*() helpers uts: port to ns_ref_*() helpers ipv4: use check_net() net: use check_net() net-sysfs: use check_net() user: port to ns_ref_*() helpers time: port to ns_ref_*() helpers pid: port to ns_ref_*() helpers ipc: port to ns_ref_*() helpers cgroup: port to ns_ref_*() helpers ...
2025-09-29Merge tag 'kernel-6.18-rc1.clone3' of ↵Linus Torvalds-1/+1
git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs Pull copy_process updates from Christian Brauner: "This contains the changes to enable support for clone3() on nios2 which apparently is still a thing. The more exciting part of this is that it cleans up the inconsistency in how the 64-bit flag argument is passed from copy_process() into the various other copy_*() helpers" [ Fixed up rv ltl_monitor 32-bit support as per Sasha Levin in the merge ] * tag 'kernel-6.18-rc1.clone3' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs: nios2: implement architecture-specific portion of sys_clone3 arch: copy_thread: pass clone_flags as u64 copy_process: pass clone_flags as u64 across calltree copy_sighand: Handle architectures where sizeof(unsigned long) < sizeof(u64)
2025-09-25ns: move ns type into struct ns_commonChristian Brauner-1/+1
It's misplaced in struct proc_ns_operations and ns->ops might be NULL if the namespace is compiled out but we still want to know the type of the namespace for the initial namespace struct. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-22cpuset: remove is_prs_invalid helperChen Ridong-8/+3
The is_prs_invalid helper function is redundant as it serves a similar purpose to is_partition_invalid. It can be fully replaced by the existing is_partition_invalid function, so this patch removes the is_prs_invalid helper. Signed-off-by: Chen Ridong <chenridong@huawei.com> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-22cpuset: remove impossible warning in update_parent_effective_cpumaskChen Ridong-1/+0
If the parent is not a valid partition, an error will be returned before any partition update command is processed. This means the WARN_ON_ONCE(!is_partition_valid(parent)) can never be triggered, so it is safe to remove. Signed-off-by: Chen Ridong <chenridong@huawei.com> Acked-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-22cpuset: remove redundant special case for null input in node mask updateChen Ridong-14/+8
The nodelist_parse function already handles empty nodemask input appropriately, making it unnecessary to handle this case separately during the node mask update process. Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-22ns: simplify ns_common_init() furtherChristian Brauner-1/+1
Simply derive the ns operations from the namespace type. Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19cpuset: fix missing error return in update_cpumaskChen Ridong-1/+2
The commit c6366739804f ("cpuset: refactor cpus_allowed_validate_change") inadvertently removed the error return when cpus_allowed_validate_change() fails. This patch restores the proper error handling by returning retval when the validation check fails. Fixes: c6366739804f ("cpuset: refactor cpus_allowed_validate_change") Signed-off-by: Chen Ridong <chenridong@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-19cpuset: Use new excpus for nocpu error check when enabling root partitionChen Ridong-5/+1
A previous patch fixed a bug where new_prs should be assigned before checking housekeeping conflicts. This patch addresses another potential issue: the nocpu error check currently uses the xcpus which is not updated. Although no issue has been observed so far, the check should be performed using the new effective exclusive cpus. The comment has been removed because the function returns an error if nocpu checking fails, which is unrelated to the parent. Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-19cpuset: fix failure to enable isolated partition when containing isolcpusChen Ridong-1/+1
The 'isolcpus' parameter specified at boot time can be assigned to an isolated partition. While it is valid put the 'isolcpus' in an isolated partition, attempting to change a member cpuset to an isolated partition will fail if the cpuset contains any 'isolcpus'. For example, the system boots with 'isolcpus=9', and the following configuration works correctly: # cd /sys/fs/cgroup/ # mkdir test # echo 1 > test/cpuset.cpus # echo isolated > test/cpuset.cpus.partition # cat test/cpuset.cpus.partition isolated # echo 9 > test/cpuset.cpus # cat test/cpuset.cpus.partition isolated # cat test/cpuset.cpus 9 However, the following steps to convert a member cpuset to an isolated partition will fail: # cd /sys/fs/cgroup/ # mkdir test # echo 9 > test/cpuset.cpus # echo isolated > test/cpuset.cpus.partition # cat test/cpuset.cpus.partition isolated invalid (partition config conflicts with housekeeping setup) The issue occurs because the new partition state (new_prs) is used for validation against housekeeping constraints before it has been properly updated. To resolve this, move the assignment of new_prs before the housekeeping validation check when enabling a root partition. Fixes: 4a74e418881f ("cgroup/cpuset: Check partition conflict with housekeeping setup") Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2025-09-19ns: use inode initializer for initial namespacesChristian Brauner-1/+1
Just use the common helper we have. Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19ns: rename to __ns_refChristian Brauner-1/+1
Make it easier to grep and rename to ns_count. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19ns: add ns_common_free()Christian Brauner-1/+1
And drop ns_free_inum(). Anything common that can be wasted centrally should be wasted in the new common helper. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19nscommon: simplify initializationChristian Brauner-1/+1
There's a lot of information that namespace implementers don't need to know about at all. Encapsulate this all in the initialization helper. Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19ns: add to_<type>_ns() to respective headersChristian Brauner-5/+0
Every namespace type has a container_of(ns, <ns_type>, ns) static inline function that is currently not exposed in the header. So we have a bunch of places that open-code it via container_of(). Move it to the headers so we can use it directly. Reviewed-by: Aleksa Sarai <cyphar@cyphar.com> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19cgroup: support ns lookupChristian Brauner-2/+7
Support the generic ns lookup infrastructure to support file handles for namespaces. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19Merge branch 'no-rebase-mnt_ns_tree_remove'Christian Brauner-6/+8
Bring in the fix for removing a mount namespace from the mount namespace rbtree and list. Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-19cgroup: use ns_common_init()Christian Brauner-8/+4
Don't cargo-cult the same thing over and over. Acked-by: Tejun Heo <tj@kernel.org> Reviewed-by: Jan Kara <jack@suse.cz> Signed-off-by: Christian Brauner <brauner@kernel.org>
2025-09-17cpuset: use partition_cpus_change for setting exclusive cpusChen Ridong-27/+2
A previous patch has introduced a new helper function partition_cpus_change(). Now replace the exclusive cpus setting logic with this helper function. Signed-off-by: Chen Ridong <chenridong@huawei.com> Reviewed-by: Waiman Long <longman@redhat.com> Signed-off-by: Tejun Heo <tj@kernel.org>