linux-yocto/kernel
Waiman Long 933563ad9b cgroup/cpuset: Fix a partition error with CPU hotplug
[ Upstream commit 150e298ae0ccbecff2357a72fbabd80f8849ea6e ]

It was found during testing that an invalid leaf partition with an
empty effective exclusive CPU list can become a valid empty partition
with no CPU afer an offline/online operation of an unrelated CPU. An
empty partition root is allowed in the special case that it has no
task in its cgroup and has distributed out all its CPUs to its child
partitions. That is certainly not the case here.

The problem is in the cpumask_subsets() test in the hotplug case
(update with no new mask) of update_parent_effective_cpumask() as it
also returns true if the effective exclusive CPU list is empty. Fix that
by addding the cpumask_empty() test to root out this exception case.
Also add the cpumask_empty() test in cpuset_hotplug_update_tasks()
to avoid calling update_parent_effective_cpumask() for this special case.

Fixes: 0c7f293efc ("cgroup/cpuset: Add cpuset.cpus.exclusive.effective for v2")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-08-28 16:34:43 +02:00
..
bpf bpf: Make reg_not_null() true for CONST_PTR_TO_MAP 2025-08-20 18:41:20 +02:00
cgroup cgroup/cpuset: Fix a partition error with CPU hotplug 2025-08-28 16:34:43 +02:00
configs Kbuild updates for v6.16 2025-06-07 10:05:35 -07:00
debug TTY/Serial driver updates for 6.15-rc1 2025-04-02 18:17:33 -07:00
dma dma-contiguous: hornor the cma address limit setup by user 2025-06-12 08:38:40 +02:00
entry entry: Inline syscall_exit_to_user_mode() 2025-04-29 08:27:10 +02:00
events perf/core: Prevent VMA split of buffer mappings 2025-08-15 16:39:31 +02:00
futex futex: Use user_write_access_begin/_end() in futex_put_value() 2025-08-20 18:41:35 +02:00
gcov kbuild: require gcc-8 and binutils-2.30 2025-04-30 21:53:35 +02:00
irq genirq/irq_sim: Initialize work context pointers properly 2025-06-13 15:36:35 +02:00
kcsan kcsan: test: Initialize dummy variable 2025-08-15 16:38:50 +02:00
livepatch sched,livepatch: Untangle cond_resched() and live-patching 2025-05-14 13:16:24 +02:00
locking Generic: 2025-06-02 12:24:58 -07:00
module module: Prevent silent truncation of module name in delete_module(2) 2025-08-20 18:41:28 +02:00
power PM: sleep: console: Fix the black screen issue 2025-08-20 18:41:00 +02:00
printk printk: nbcon: Allow reacquire during panic 2025-08-20 18:41:30 +02:00
rcu rcu: Fix racy re-initialization of irq_work causing hangs 2025-08-20 18:41:43 +02:00
sched sched/ext: Fix invalid task state transitions on class switch 2025-08-28 16:34:31 +02:00
time timekeeping: Zero initialize system_counterval when querying time from phc drivers 2025-07-22 14:25:21 +02:00
trace tracing: Limit access to parser->buffer when trace_get_user failed 2025-08-28 16:34:41 +02:00
.gitignore kheaders: rebuild kheaders_data.tar.xz when a file is modified within a minute 2025-08-20 18:41:31 +02:00
acct.c acct: block access to kernel internal filesystems 2025-02-12 12:24:16 +01:00
async.c
audit_fsnotify.c
audit_tree.c replace collect_mounts()/drop_collected_mounts() with a safer variant 2025-06-23 14:01:49 -04:00
audit_watch.c fs: add kern_path_locked_negative() 2025-04-15 11:32:34 +02:00
audit.c audit: record AUDIT_ANOM_* events regardless of presence of rules 2025-04-11 14:14:41 -04:00
audit.h audit,module: restore audit logging in load failure case 2025-08-15 16:38:20 +02:00
auditfilter.c audit: fix suffixed '/' filename matching 2024-12-05 19:22:38 -05:00
auditsc.c audit,module: restore audit logging in load failure case 2025-08-15 16:38:20 +02:00
backtracetest.c
bounds.c
capability.c capability: Remove unused has_capability 2025-03-07 22:03:09 -06:00
cfi.c Modules changes for 6.15-rc1 2025-03-30 15:44:36 -07:00
compat.c
configs.c
context_tracking.c context_tracking: Make RCU watch ct_kernel_exit_state() warning 2025-03-04 18:44:29 -08:00
cpu_pm.c
cpu.c perf: Remove too early and redundant CPU hotplug handling 2025-05-08 21:50:19 +02:00
crash_core.c crash: Use note name macros 2025-02-10 16:56:58 -08:00
crash_dump_dm_crypt.c crash_dump: retrieve dm crypt keys in kdump kernel 2025-05-21 10:48:21 -07:00
crash_reserve.c crash: fix spelling mistake "crahskernel" -> "crashkernel" 2025-05-11 17:54:10 -07:00
cred.c cred: remove old {override,revert}_creds() helpers 2024-12-02 11:25:09 +01:00
delayacct.c delayacct: remove redundant code and adjust indentation 2025-05-27 19:40:33 -07:00
dma.c
elfcorehdr.c
exec_domain.c
exit.c - Avoid a crash on a heterogeneous machine where not all cores support the 2025-06-22 10:11:45 -07:00
exit.h
extable.c
fail_function.c
fork.c - The 11 patch series "Add folio_mk_pte()" from Matthew Wilcox 2025-05-31 15:44:16 -07:00
freezer.c sched,freezer: Remove unnecessary warning in __thaw_task 2025-07-17 07:56:50 -10:00
gen_kheaders.sh kheaders: rebuild kheaders_data.tar.xz when a file is modified within a minute 2025-08-20 18:41:31 +02:00
groups.c
hung_task.c hung_task: show the blocker task if the task is hung on semaphore 2025-05-11 17:54:08 -07:00
iomem.c mm/memremap: Pass down MEMREMAP_* flags to arch_memremap_wb() 2025-02-21 15:05:38 +01:00
irq_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
jump_label.c jump_label: Use RCU in all users of __module_text_address(). 2025-03-10 11:54:46 +01:00
kallsyms_internal.h
kallsyms_selftest.c kallsyms: Use kthread_run_on_cpu() 2025-01-02 22:12:12 +01:00
kallsyms_selftest.h
kallsyms.c kallsyms: Remove KALLSYMS_ABSOLUTE_PERCPU 2025-02-18 10:16:04 +01:00
kcmp.c kcmp: improve performance adding an unlikely hint to task comparisons 2025-02-21 10:25:33 +01:00
Kconfig.freezer
Kconfig.hz kernel: Fix "select" wording on HZ_250 description 2025-02-21 09:20:30 +01:00
Kconfig.kexec kho: mm: don't allow deferred struct page with KHO 2025-08-28 16:34:34 +02:00
Kconfig.locks
Kconfig.preempt
kcov.c kcov: mark in_softirq_really() as __always_inline 2024-12-30 17:59:08 -08:00
kexec_core.c kexec_core: Fix error code path in the KEXEC_JUMP flow 2025-08-15 16:38:34 +02:00
kexec_elf.c kexec: initialize ELF lowest address to ULONG_MAX 2025-03-16 22:30:47 -07:00
kexec_file.c - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
kexec_handover.c kho: warn if KHO is disabled due to an error 2025-08-28 16:34:35 +02:00
kexec_internal.h kexec: add KHO support to kexec file loads 2025-05-12 23:50:40 -07:00
kexec.c
kheaders.c kheaders: Simplify attribute through __BIN_ATTR_SIMPLE_RO() 2024-12-24 09:46:49 +01:00
kprobes.c kprobes: Use RCU in all users of __module_text_address(). 2025-03-10 11:54:46 +01:00
ksyms_common.c
ksysfs.c kernel/ksysfs.c: simplify bin_attribute definition 2025-01-07 16:59:15 +01:00
kthread.c ipvs: Fix estimator kthreads preferred affinity 2025-08-20 18:40:52 +02:00
latencytop.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
Makefile kheaders: rebuild kheaders_data.tar.xz when a file is modified within a minute 2025-08-20 18:41:31 +02:00
module_signature.c
notifier.c
nsproxy.c kernel/nsproxy: remove unnecessary guards 2025-05-09 13:13:54 +02:00
padata.c padata: Fix pd UAF once and for all 2025-08-15 16:38:58 +02:00
panic.c - The 3 patch series "hung_task: extend blocking task stacktrace dump to 2025-05-31 19:12:53 -07:00
params.c module: ensure that kobject_put() is safe for module type kobjects 2025-05-07 20:24:59 +02:00
pid_namespace.c pid: Do not set pid_max in new pid namespaces 2025-03-06 10:18:36 +01:00
pid_sysctl.h treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
pid.c pidfs: detect refcount bugs 2025-05-06 13:59:00 +02:00
profile.c
ptrace.c ptrace: introduce PTRACE_SET_SYSCALL_INFO request 2025-05-11 17:48:15 -07:00
range.c
reboot.c - The 7 patch series "powerpc/crash: use generic crashkernel 2025-04-01 10:06:52 -07:00
regset.c
relay.c relay: remove unused relay_late_setup_files 2025-05-11 17:54:09 -07:00
resource_kunit.c
resource.c resource: fix false warning in __request_region() 2025-07-24 17:57:59 -07:00
rseq.c rseq: Fix segfault on registration when rseq_cs is non-zero 2025-03-06 22:26:49 +01:00
scftorture.c
scs.c
seccomp.c seccomp: avoid the lock trip seccomp_filter_release in common case 2025-02-24 11:17:10 -08:00
signal.c signal: Fix memory leak for PIDFD_SELF* sentinels 2025-08-28 16:34:38 +02:00
smp.c CSD-lock pull request for v6.14 2025-01-28 11:34:03 -08:00
smpboot.c
smpboot.h
softirq.c lockdep: Fix wait context check on softirq for PREEMPT_RT 2025-03-25 10:46:44 +01:00
stackleak.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
stacktrace.c
static_call_inline.c Modules changes for 6.15-rc1 2025-03-30 15:44:36 -07:00
static_call.c
stop_machine.c sched/core: Fix migrate_swap() vs. hotplug 2025-07-01 15:02:03 +02:00
sys_ni.c
sys.c futex: Add basic infrastructure for local task local hash 2025-05-03 12:02:07 +02:00
sysctl-test.c sysctl: move u8 register test to lib/test_sysctl.c 2025-04-14 14:13:41 +02:00
sysctl.c sparc: mv sparc sysctls into their own file under arch/sparc/kernel 2025-04-09 13:32:16 +02:00
task_work.c kasan: make kasan_record_aux_stack_noalloc() the default behaviour 2025-01-13 22:40:36 -08:00
taskstats.c
torture.c torture: Add get_torture_init_jiffies() for test-start time 2025-02-05 07:14:24 -08:00
tracepoint.c tracepoint: Print the function symbol when tracepoint_debug is set 2025-03-21 15:30:10 -04:00
tsacct.c
ucount.c ucount: fix atomic_long_inc_below() argument type 2025-08-15 16:39:17 +02:00
uid16.c
uid16.h
umh.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
up.c
user_namespace.c uidgid: add map_id_range_up() 2025-02-12 12:12:27 +01:00
user-return-notifier.c
user.c
usermode_driver.c
utsname_sysctl.c treewide: const qualify ctl_tables where applicable 2025-01-28 13:48:37 +01:00
utsname.c
vhost_task.c vhost_task: fix vhost_task_create() documentation 2025-04-18 10:08:11 -04:00
vmcore_info.c crash: export PAGE_UNACCEPTED_MAPCOUNT_VALUE to vmcoreinfo 2025-05-11 17:54:04 -07:00
watch_queue.c vfs-6.15-rc1.pipe 2025-03-24 09:52:37 -07:00
watchdog_buddy.c
watchdog_perf.c - The 7 patch series "powerpc/crash: use generic crashkernel 2025-04-01 10:06:52 -07:00
watchdog.c kernel/watchdog: add /sys/kernel/{hard,soft}lockup_count 2025-05-21 10:48:22 -07:00
workqueue_internal.h
workqueue.c workqueue: Initialize wq_isolated_cpumask in workqueue_init_early() 2025-06-17 08:58:29 -10:00