linux/kernel
Linus Torvalds 3cb9871f81 Urgent RCU pull request for v6.8
This commit fixes RCU grace period stalls, which are observed when
 an outgoing CPU's quiescent state reporting results in wakeup of
 one of the grace period kthreads, to complete the grace period. If
 those kthreads have SCHED_FIFO policy, the wake up can indirectly
 arm the RT bandwith timer to the local offline CPU. Earlier migration
 of the hrtimers from the CPU introduced in commit 5c0930ccaa
 ("hrtimers: Push pending hrtimers away from outgoing CPU earlier")
 results in this timer getting ignored. If the RCU grace period
 kthreads are waiting for RT bandwidth to be available, they may
 never be actually scheduled, resulting in RCU stall warnings.
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Merge tag 'urgent-rcu.2024.01.24a' of https://github.com/neeraju/linux

Pull RCU fix from Neeraj Upadhyay:
 "This fixes RCU grace period stalls, which are observed when an
  outgoing CPU's quiescent state reporting results in wakeup of one of
  the grace period kthreads, to complete the grace period.

  If those kthreads have SCHED_FIFO policy, the wake up can indirectly
  arm the RT bandwith timer to the local offline CPU.

  Earlier migration of the hrtimers from the CPU introduced in commit
  5c0930ccaa ("hrtimers: Push pending hrtimers away from outgoing CPU
  earlier") results in this timer getting ignored.

  If the RCU grace period kthreads are waiting for RT bandwidth to be
  available, they may never be actually scheduled, resulting in RCU
  stall warnings"

* tag 'urgent-rcu.2024.01.24a' of https://github.com/neeraju/linux:
  rcu: Defer RCU kthreads wakeup when CPU is dying
2024-01-25 10:21:21 -08:00
..
bpf
cgroup
configs
debug
dma
entry
events
futex
gcov
irq As usual, lots of singleton and doubleton patches all over the tree and 2023-11-02 20:53:31 -10:00
kcsan
livepatch
locking
module
power
printk
rcu
sched
time
trace
.gitignore
acct.c
async.c
audit.c
audit.h
audit_fsnotify.c
audit_tree.c
audit_watch.c
auditfilter.c
auditsc.c
backtracetest.c
bounds.c
capability.c
cfi.c
compat.c
configs.c
context_tracking.c
cpu.c
cpu_pm.c
crash_core.c
crash_dump.c
cred.c
delayacct.c
dma.c
exec_domain.c
exit.c
exit.h
extable.c
fail_function.c
fork.c
freezer.c
gen_kheaders.sh
groups.c
hung_task.c
iomem.c
irq_work.c
jump_label.c
kallsyms.c
kallsyms_internal.h
kallsyms_selftest.c
kallsyms_selftest.h
kcmp.c
Kconfig.freezer
Kconfig.hz
Kconfig.kexec
Kconfig.locks
Kconfig.preempt
kcov.c
kexec.c
kexec_core.c
kexec_elf.c
kexec_file.c
kexec_internal.h
kheaders.c
kprobes.c
ksyms_common.c
ksysfs.c
kthread.c
latencytop.c
Makefile
module_signature.c
notifier.c
nsproxy.c
numa.c
padata.c
panic.c
params.c
pid.c
pid_namespace.c
pid_sysctl.h
profile.c
ptrace.c
range.c
reboot.c
regset.c
relay.c
resource.c
resource_kunit.c
rseq.c
scftorture.c
scs.c
seccomp.c
signal.c
smp.c
smpboot.c
smpboot.h
softirq.c
stackleak.c
stacktrace.c
static_call.c
static_call_inline.c
stop_machine.c
sys.c
sys_ni.c
sysctl-test.c
sysctl.c
task_work.c
taskstats.c
torture.c
tracepoint.c
tsacct.c
ucount.c
uid16.c
uid16.h
umh.c
up.c
user-return-notifier.c
user.c
user_namespace.c
usermode_driver.c
utsname.c
utsname_sysctl.c
vhost_task.c
watch_queue.c
watchdog.c
watchdog_buddy.c
watchdog_perf.c
workqueue.c
workqueue_internal.h