linux-yocto/kernel
Chen Yu f27f949622 kthread: fix task state in kthread worker if being frozen
[ Upstream commit e16c7b0778 ]

When analyzing a kernel waring message, Peter pointed out that there is a
race condition when the kworker is being frozen and falls into
try_to_freeze() with TASK_INTERRUPTIBLE, which could trigger a
might_sleep() warning in try_to_freeze().  Although the root cause is not
related to freeze()[1], it is still worthy to fix this issue ahead.

One possible race scenario:

        CPU 0                                           CPU 1
        -----                                           -----

        // kthread_worker_fn
        set_current_state(TASK_INTERRUPTIBLE);
                                                       suspend_freeze_processes()
                                                         freeze_processes
                                                           static_branch_inc(&freezer_active);
                                                         freeze_kernel_threads
                                                           pm_nosig_freezing = true;
        if (work) { //false
          __set_current_state(TASK_RUNNING);

        } else if (!freezing(current)) //false, been frozen

                      freezing():
                      if (static_branch_unlikely(&freezer_active))
                        if (pm_nosig_freezing)
                          return true;
          schedule()
	}

        // state is still TASK_INTERRUPTIBLE
        try_to_freeze()
          might_sleep() <--- warning

Fix this by explicitly set the TASK_RUNNING before entering
try_to_freeze().

Link: https://lore.kernel.org/lkml/Zs2ZoAcUsZMX2B%2FI@chenyu5-mobl2/ [1]
Link: https://lkml.kernel.org/r/20240827112308.181081-1-yu.c.chen@intel.com
Fixes: b56c0d8937 ("kthread: implement kthread_worker")
Signed-off-by: Chen Yu <yu.c.chen@intel.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: David Gow <davidgow@google.com>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Mickaël Salaün <mic@digikod.net>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-10-17 15:20:58 +02:00
..
bpf bpf: correctly handle malformed BPF_CORE_TYPE_ID_LOCAL relos 2024-10-17 15:20:58 +02:00
cgroup cgroup: Protect css->cgroup write under css_set_lock 2024-09-12 11:10:22 +02:00
configs Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
debug kdb: Use the passed prompt in kdb_position_cursor() 2024-08-03 08:49:47 +02:00
dma dma-mapping: benchmark: Don't starve others when doing the test 2024-09-12 11:10:23 +02:00
entry entry: Respect changes to system call number by trace_sys_enter() 2024-04-03 15:19:44 +02:00
events perf/aux: Fix AUX buffer serialization 2024-09-12 11:10:27 +02:00
futex futex: Don't include process MM in futex key on no-MMU 2023-11-20 11:51:50 +01:00
gcov gcov: add support for GCC 14 2024-06-27 13:46:22 +02:00
irq genirq/irqdesc: Honor caller provided affinity in alloc_desc() 2024-08-14 13:52:58 +02:00
kcsan kcsan: Don't expect 64 bits atomic builtins from 32 bits architectures 2023-07-19 16:21:37 +02:00
livepatch livepatch: Fix missing newline character in klp_resolve_symbols() 2023-11-20 11:52:10 +01:00
locking rtmutex: Drop rt_mutex::wait_lock before scheduling 2024-09-12 11:10:17 +02:00
module modules: wait do_free_init correctly 2024-03-26 18:20:52 -04:00
power PM: s2idle: Make sure CPUs will wakeup directly on resume 2024-04-17 11:18:22 +02:00
printk printk: Update @console_may_schedule in console_trylock_spinning() 2024-04-03 15:19:44 +02:00
rcu rcu/nocb: Fix RT throttling hrtimer armed from offline CPU 2024-10-17 15:20:49 +02:00
sched sched/smt: Fix unbalance sched_smt_present dec/inc 2024-08-14 13:53:00 +02:00
time hrtimer: Prevent queuing of hrtimer without a function callback 2024-08-29 17:30:41 +02:00
trace tracing: Avoid possible softlockup in tracing_iter_reset() 2024-09-12 11:10:18 +02:00
.gitignore
acct.c acct: fix potential integer overflow in encode_comp_t() 2022-12-31 13:32:58 +01:00
async.c async: Introduce async_schedule_dev_nocall() 2024-01-31 16:17:00 -08:00
audit_fsnotify.c audit: fix potential double free on error path from fsnotify_add_inode_mark 2022-08-22 18:50:06 -04:00
audit_tree.c
audit_watch.c audit: don't WARN_ON_ONCE(!current->mm) in audit_exe_compare() 2023-11-28 17:07:08 +00:00
audit.c audit: Send netlink ACK before setting connection in auditd_set 2024-02-05 20:12:47 +00:00
audit.h audit: remove selinux_audit_rule_update() declaration 2022-09-07 11:30:15 -04:00
auditfilter.c ima: Avoid blocking in RCU read-side critical section 2024-07-11 12:47:16 +02:00
auditsc.c audit,io_uring: io_uring openat triggers audit reference count underflow 2023-10-25 12:03:04 +02:00
backtracetest.c
bounds.c bounds: Use the right number of bits for power-of-two CONFIG_NR_CPUS 2024-05-02 16:29:32 +02:00
capability.c
cfi.c cfi: Switch to -fsanitize=kcfi 2022-09-26 10:13:13 -07:00
compat.c sched_getaffinity: don't assume 'cpumask_size()' is fully initialized 2023-04-06 12:10:40 +02:00
configs.c
context_tracking.c context_tracking: Fix noinstr vs KASAN 2023-03-10 09:33:45 +01:00
cpu_pm.c
cpu.c cpu/hotplug: Fix dynstate assignment in __cpuhp_setup_state_cpuslocked() 2024-07-05 09:31:56 +02:00
crash_core.c vmcoreinfo: add kallsyms_num_syms symbol 2022-08-28 14:02:44 -07:00
crash_dump.c
cred.c cred: switch to using atomic_long_t 2023-12-20 17:00:20 +01:00
delayacct.c delayacct: support re-entrance detection of thrashing accounting 2022-09-26 19:46:07 -07:00
dma.c
exec_domain.c
exit.c mm: optimize the redundant loop of mm_update_owner_next() 2024-07-11 12:47:13 +02:00
extable.c
fail_function.c kernel/fail_function: fix memory leak with using debugfs_lookup() 2023-03-11 13:55:39 +01:00
fork.c Revert "fork: defer linking file vma until vma is fully initialized" 2024-06-21 14:35:59 +02:00
freezer.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
gen_kheaders.sh kheaders: explicitly define file modes for archived headers 2024-06-27 13:46:24 +02:00
groups.c
hung_task.c sched: Fix more TASK_state comparisons 2022-09-30 16:50:39 +02:00
iomem.c
irq_work.c
jump_label.c jump_label: Fix the fix, brown paper bags galore 2024-08-14 13:52:43 +02:00
kallsyms_internal.h kallsyms: Reduce the memory occupied by kallsyms_seqs_of_names[] 2023-10-25 12:03:16 +02:00
kallsyms.c kallsyms: Add helper kallsyms_on_each_match_symbol() 2023-10-25 12:03:16 +02:00
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kcov.c kcov: properly check for softirq context 2024-08-14 13:52:58 +02:00
kexec_core.c kexec: fix a memory leak in crash_shrink_memory() 2023-07-19 16:21:08 +02:00
kexec_elf.c
kexec_file.c kexec: support purgatories with .text.hot sections 2023-06-21 16:00:55 +02:00
kexec_internal.h panic, kexec: make __crash_kexec() NMI safe 2022-09-11 21:55:06 -07:00
kexec.c kernel: kexec: copy user-array safely 2023-11-28 17:06:57 +00:00
kheaders.c kheaders: Use array declaration instead of char 2023-05-11 23:03:02 +09:00
kmod.c
kprobes.c kprobes: Fix to check symbol prefixes correctly 2024-08-14 13:52:54 +02:00
ksysfs.c kexec: turn all kexec_mutex acquisitions into trylocks 2022-09-11 21:55:06 -07:00
kthread.c kthread: fix task state in kthread worker if being frozen 2024-10-17 15:20:58 +02:00
latencytop.c latencytop: use the last element of latency_record of system 2022-09-11 21:55:12 -07:00
Makefile kernel/numa.c: Move logging out of numa.h 2024-06-12 11:03:16 +02:00
module_signature.c
notifier.c
nsproxy.c Revert "fs/exec: allow to unshare a time namespace on vfork+exec" 2022-09-13 10:38:43 -07:00
numa.c kernel/numa.c: Move logging out of numa.h 2024-06-12 11:03:16 +02:00
padata.c padata: Honor the caller's alignment in case of chunk_size 0 2024-10-17 15:20:38 +02:00
panic.c panic: Flush kernel log buffer at the end 2024-04-13 13:04:54 +02:00
params.c
pid_namespace.c pid: Replace struct pid 1-element array with flex-array 2024-08-29 17:30:18 +02:00
pid.c pid: Replace struct pid 1-element array with flex-array 2024-08-29 17:30:18 +02:00
profile.c profiling: remove profile=sleep support 2024-08-14 13:52:50 +02:00
ptrace.c freezer,sched: Rewrite core freezer logic 2022-09-07 21:53:50 +02:00
range.c
reboot.c kernel/reboot: emergency_restart: Set correct system_state 2023-11-28 17:07:13 +00:00
regset.c
relay.c relayfs: fix out-of-bounds access in relay_file_read 2023-05-11 23:03:03 +09:00
resource_kunit.c
resource.c x86/kaslr: Expose and use the end of the physical memory address space 2024-09-12 11:10:17 +02:00
rseq.c rseq: Use pr_warn_once() when deprecated/unknown ABI flags are encountered 2022-11-14 09:58:32 +01:00
scftorture.c scftorture: Forgive memory-allocation failure if KASAN 2023-09-23 11:11:00 +02:00
scs.c
seccomp.c
signal.c kernel: rerun task_work while freezing in get_signal() 2024-08-03 08:49:31 +02:00
smp.c smp: Add missing destroy_work_on_stack() call in smp_call_on_cpu() 2024-09-12 11:10:24 +02:00
smpboot.c smpboot: use atomic_try_cmpxchg in cpu_wait_death and cpu_report_death 2022-09-11 21:55:10 -07:00
smpboot.h
softirq.c softirq: Fix suspicious RCU usage in __do_softirq() 2024-06-12 11:03:01 +02:00
stackleak.c
stacktrace.c
static_call_inline.c
static_call.c
stop_machine.c
sys_ni.c syscalls: fix compat_sys_io_pgetevents_time64 usage 2024-07-05 09:31:59 +02:00
sys.c getrusage: use sig->stats_lock rather than lock_task_sighand() 2024-03-15 10:48:22 -04:00
sysctl-test.c kernel/sysctl-test: use SYSCTL_{ZERO/ONE_HUNDRED} instead of i_{zero/one_hundred} 2022-09-08 16:56:45 -07:00
sysctl.c proc: proc_skip_spaces() shouldn't think it is working on C strings 2022-12-05 12:09:06 -08:00
task_work.c task_work: Introduce task_work_cancel() again 2024-08-03 08:49:34 +02:00
taskstats.c genetlink: start to validate reserved header bytes 2022-08-29 12:47:15 +01:00
torture.c torture: Fix hang during kthread shutdown phase 2023-03-10 09:34:07 +01:00
tracepoint.c tracepoint: Optimize the critical region of mutex_lock in tracepoint_module_coming() 2022-09-26 13:01:18 -04:00
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c freezer,umh: Fix call_usermode_helper_exec() vs SIGKILL 2023-02-22 12:59:50 +01:00
up.c
user_namespace.c ucounts: Split rlimit and ucount values and max values 2022-10-09 16:24:05 -07:00
user-return-notifier.c
user.c
usermode_driver.c
utsname_sysctl.c kernel/utsname_sysctl.c: Fix hostname polling 2022-10-23 12:01:01 -07:00
utsname.c
watch_queue.c kernel: watch_queue: copy user-array safely 2023-11-28 17:06:57 +00:00
watchdog_hld.c watchdog/perf: properly initialize the turbo mode timestamp and rearm counter 2024-08-03 08:49:42 +02:00
watchdog.c watchdog: move softlockup_panic back to early_param 2023-11-28 17:07:09 +00:00
workqueue_internal.h
workqueue.c workqueue: Improve scalability of workqueue watchdog touch 2024-09-12 11:10:27 +02:00