The current rcu_gp_kthread_wake() function uses in_interrupt()
and thus does a self-wakeup from all interrupt contexts, including
the pointless case where the GP kthread happens to be running with
bottom halves disabled, along with the impossible case where the GP
kthread is running within an NMI handler (you are not supposed to invoke
rcu_gp_kthread_wake() from within an NMI handler. This commit therefore
replaces the in_interrupt() with in_irq(), so that the self-wakeups
happen only from handlers for hardware interrupts and softirqs.
This also makes the code match the comment.
Change-Id: Icdc3a9a03d6a58d59cf4e81911ad7b48651c82f0
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: mydongistiny <jaysonedson@gmail.com>
Signed-off-by: CloudedQuartz <ravenklawasd@gmail.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Neeraj Upadhyayauthored and Sorayukiicommited 2026-05-15 17:49:36 +07:00
This commit adds RCU-reader checks to list_for_each_entry_rcu() and
hlist_for_each_entry_rcu(). These checks are optional, and are indicated
by a lockdep expression passed to a new optional argument to these two
macros. If this optional lockdep expression is omitted, these two macros
act as before, checking for an RCU read-side critical section.
Change-Id: I102aad99348529184666a56bf3bf4458ae63520c
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Update to eliminate return within macro and update comment. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Joel Fernandes (Google)authored and Sorayukiicommited 2026-05-15 17:49:36 +07:00
When there are no callbacks pending on an idle system, I noticed that
RCU softirq is continuously firing. During this the cpu_no_qs is set to
false, and core_needs_qs is set to true indefinitely. This causes
rcu_process_callbacks to be repeatedly called, even though the node
corresponding to the CPU has that CPU's mask bit cleared and the system
is idle. I believe the race is when such mask clearing is done during
idle CPU scan of the quiescent state forcing stage in the kthread
instead of the softirq. Since the rnp mask is cleared, but the flags on
the CPU's rdp are not cleared, the CPU thinks it still needs to report
to core RCU.
Cure this by clearing the core_needs_qs flag when the CPU detects that
its node is already updated which will avoid the unwanted softirq raises
to the benefit of real-time systems.
Test: Ran rcutorture for various tree RCU configs.
Change-Id: Iee374d1dcdc74ecc5e6816a99be51feddd876931
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: mydongistiny <jaysonedson@gmail.com>
Signed-off-by: CloudedQuartz <ravenklawasd@gmail.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Joel Fernandes (Google)authored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
The rcu_pm_notify() function refuses to switch to/from expedited grace
periods on systems with more than 256 CPUs due to the serialized
initialization of expedited grace periods. However, expedited grace
periods are now initialized in parallel, removing this concern.
This commit therefore removes the checks from rcu_pm_notify(), so that
expedited grace periods are used unconditionally during suspend/resume
and hibernate/wake operations.
As always, real-time workloads wishing to completely avoid expedited
grace periods can use the rcupdate.rcu_normal= kernel parameter.
Change-Id: I0dbdf150b64a33dd82c0f9b56c003cf0339b1ad6
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: mydongistiny <jaysonedson@gmail.com>
Signed-off-by: CloudedQuartz <ravenklawasd@gmail.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
Joel Fernandes found that the synchronize_rcu_tasks() was taking a
significant amount of time. He demonstrated it with the following test:
# cd /sys/kernel/tracing
# while [ 1 ]; do x=1; done &
# echo '__schedule_bug:traceon' > set_ftrace_filter
# time echo '!__schedule_bug:traceon' > set_ftrace_filter;
real 0m1.064s
user 0m0.000s
sys 0m0.004s
Where it takes a little over a second to perform the synchronize,
because there's a loop that waits 1 second at a time for tasks to get
through their quiescent points when there's a task that must be waited
for.
After discussion we came up with a simple way to wait for holdouts but
increase the time for each iteration of the loop but no more than a
full second.
With the new patch we have:
# time echo '!__schedule_bug:traceon' > set_ftrace_filter;
real 0m0.131s
user 0m0.000s
sys 0m0.004s
Which drops it down to 13% of what the original wait time was.
Change-Id: I05400f8940752e548d0395d11a85e192642fb688
Link: http://lkml.kernel.org/r/20180523063815.198302-2-joel@joelfernandes.org
Reported-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Suggested-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: celtare21 <celtare21@gmail.com>
Signed-off-by: Danny Lin <danny@kdrag0n.dev>
Signed-off-by: CloudedQuartz <ravenklawasd@gmail.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Steven Rostedt (VMware)authored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
Commit "rcu: Create RCU-specific workqueues with rescuers" switched RCU
to using local workqueses and removed power efficiency flag from them.
This caused a performance regression that can be observed in Geekbench 5
after enabling CONFIG_WQ_POWER_EFFICIENT_DEFAULT: score went down from
760/2500 to 620/2300 (single/multi core respectively).
Add WQ_POWER_EFFICIENT flag to avoid this regression.
Signed-off-by: Yaroslav Furman <yaro330@gmail.com>
Signed-off-by: Adam W. Willis <return.of.octobot@gmail.com>
Signed-off-by: DennySPB <dennyspb@gmail.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Yaroslav Furmanauthored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
[ Upstream commit 8b9b443fa860276822b25057cb3ff3b28734dec0 ]
The "pipe_count > RCU_TORTURE_PIPE_LEN" check has a comment saying "Should
not happen, but...". This is only true when testing an RCU whose grace
periods are always long enough. This commit therefore fixes this comment.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Closes: https://lore.kernel.org/lkml/CAHk-=wi7rJ-eGq+xaxVfzFEgbL9tdf6Kc8Z89rCpfcQOKm74Tw@mail.gmail.com/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
(cherry picked from commit 6652029853316f4c273219145ef0e71b148bbe01)
Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
[ Upstream commit 2d7f00b2f01301d6e41fd4a28030dab0442265be ]
The normal grace period's RCU CPU stall warnings are invoked from the
scheduling-clock interrupt handler, and can thus invoke smp_processor_id()
with impunity, which allows them to directly invoke dump_cpu_task().
In contrast, the expedited grace period's RCU CPU stall warnings are
invoked from process context, which causes the dump_cpu_task() function's
calls to smp_processor_id() to complain bitterly in debug kernels.
This commit therefore causes synchronize_rcu_expedited_wait() to disable
preemption around its call to dump_cpu_task().
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
commit 92aa39e9dc77481b90cbef25e547d66cab901496 upstream.
The per-CPU rcu_dynticks.rcu_urgent_qs variable communicates an urgent
need for an RCU quiescent state from the force-quiescent-state processing
within the grace-period kthread to context switches and to cond_resched().
Unfortunately, such urgent needs are not communicated to need_resched(),
which is sometimes used to decide when to invoke cond_resched(), for
but one example, within the KVM vcpu_run() function. As of v4.15, this
can result in synchronize_sched() being delayed by up to ten seconds,
which can be problematic, to say nothing of annoying.
This commit therefore checks rcu_dynticks.rcu_urgent_qs from within
rcu_check_callbacks(), which is invoked from the scheduling-clock
interrupt handler. If the current task is not an idle task and is
not executing in usermode, a context switch is forced, and either way,
the rcu_dynticks.rcu_urgent_qs variable is set to false. If the current
task is an idle task, then RCU's dyntick-idle code will detect the
quiescent state, so no further action is required. Similarly, if the
task is executing in usermode, other code in rcu_check_callbacks() and
its called functions will report the corresponding quiescent state.
Reported-by: Marius Hillenbrand <mhillenb@amazon.de>
Reported-by: David Woodhouse <dwmw2@infradead.org>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
[ paulmck: Backported to make patch apply cleanly on older versions. ]
Tested-by: Marius Hillenbrand <mhillenb@amazon.de>
Cc: <stable@vger.kernel.org> # 4.12.x - 4.19.x
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:35 +07:00
commit 156baec39732f025dc778e00da95fc10d6e45885 upstream.
Use of init_rcu_head() and destroy_rcu_head() from modules results in
the following build-time error with CONFIG_DEBUG_OBJECTS_RCU_HEAD=y:
ERROR: "init_rcu_head" [drivers/scsi/scsi_mod.ko] undefined!
ERROR: "destroy_rcu_head" [drivers/scsi/scsi_mod.ko] undefined!
This commit therefore adds EXPORT_SYMBOL_GPL() for each to allow them to
be used by GPL-licensed kernel modules.
Reported-by: Bart Van Assche <Bart.VanAssche@wdc.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
commit 135bd1a230bb69a68c9808a7d25467318900b80a upstream.
The pending-callbacks check in rcu_prepare_for_idle() is backwards.
It should accelerate if there are pending callbacks, but the check
rather uselessly accelerates only if there are no callbacks. This commit
therefore inverts this check.
Fixes: 15fecf89e46a ("srcu: Abstract multi-tail callback list handling")
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Neeraj Upadhyayauthored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
Because many of RCU's files have not been included into docbook, a
number of errors have accumulated. This commit fixes them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
The read of ->dynticks_nmi_nesting in rcu_irq_enter() and rcu_irq_exit()
is currently protected with READ_ONCE(). However, this protection is
unnecessary because (1) ->dynticks_nmi_nesting is updated only by the
current CPU, (2) Although NMI handlers can update this field, they reset
it back to its old value before return, and (3) Interrupts are disabled,
so nothing else can modify it. The value of ->dynticks_nmi_nesting is
thus effectively constant, and so no protection is required.
This commit therefore removes the READ_ONCE() protection from these
two accesses.
Link: http://lkml.kernel.org/r/20170926031902.GA2074@linux.vnet.ibm.com
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
The rcu_idle_exit() and rcu_idle_enter() functions are exported because
they were originally used by RCU_NONIDLE(), which was intended to
be usable from modules. However, RCU_NONIDLE() now instead uses
rcu_irq_enter_irqson() and rcu_irq_exit_irqson(), which are not
exported, and there have been no complaints.
This commit therefore removes the exports from rcu_idle_exit() and
rcu_idle_enter().
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
All current callers of rcu_idle_enter() have irqs disabled, and
rcu_idle_enter() relies on this, but doesn't check. This commit
therefore adds a RCU_LOCKDEP_WARN() to add some verification to the trust.
While we are there, pass "true" rather than "1" to rcu_eqs_enter().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
All callers to rcu_idle_enter() have irqs disabled, so there is no
point in rcu_idle_enter disabling them again. This commit therefore
replaces the irq disabling with a RCU_LOCKDEP_WARN().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Peter Zijlstra (Intel)authored and Sorayukiicommited 2026-05-15 17:49:34 +07:00
This commit adds assertions verifying the consistency of the rcu_node
structure's ->blkd_tasks list and its ->gp_tasks, ->exp_tasks, and
->boost_tasks pointers. In particular, the ->blkd_tasks lists must be
empty except for leaf rcu_node structures.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
The _rcu_barrier_trace() function is a wrapper for trace_rcu_barrier(),
which needs TPS() protection for strings passed through the second
argument. However, it has escaped prior TPS()-ification efforts because
it _rcu_barrier_trace() does not start with "trace_". This commit
therefore adds the needed TPS() protection
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
There is currently event tracing to track when a task is preempted
within a preemptible RCU read-side critical section, and also when that
task subsequently reaches its outermost rcu_read_unlock(), but none
indicating when a new grace period starts when that grace period must
wait on pre-existing readers that have been been preempted at least once
since the beginning of their current RCU read-side critical sections.
This commit therefore adds an event trace at grace-period start in
the case where there are such readers. Note that only the first
reader in the list is traced.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
This commit saves a few lines in kernel/rcu/rcu.h by moving to single-line
definitions for trivial functions, instead of the old style where the
two curly braces each get their own line.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
Strings used in event tracing need to be specially handled, for example,
using the TPS() macro. Without the TPS() macro, although output looks
fine from within a running kernel, extracting traces from a crash dump
produces garbage instead of strings. This commit therefore adds the TPS()
macro to some unadorned strings that were passed to event-tracing macros.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
Currently, the exit-time support for TASKS_RCU is open-coded in do_exit().
This commit creates exit_tasks_rcu_start() and exit_tasks_rcu_finish()
APIs for do_exit() use. This has the benefit of confining the use of the
tasks_rcu_exit_srcu variable to one file, allowing it to become static.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
The actual use of TASKS_RCU is only when PREEMPT, otherwise RCU-sched
is used instead. This commit therefore makes synchronize_rcu_tasks()
and call_rcu_tasks() available always, but mapped to synchronize_sched()
and call_rcu_sched(), respectively, when !PREEMPT. This approach also
allows some #ifdefs to be removed from rcutorture.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:33 +07:00
Tree RCU guarantees that every online CPU has a memory barrier between
any given grace period and any of that CPU's RCU read-side sections that
must be ordered against that grace period. Since RCU doesn't always
know where read-side critical sections are, the actual implementation
guarantees order against prior and subsequent non-idle non-offline code,
whether in an RCU read-side critical section or not. As a result, there
does not need to be a memory barrier at the end of synchronize_rcu()
and friends because the ordering internal to the grace period has
ordered every CPU's post-grace-period execution against each CPU's
pre-grace-period execution, again for all non-idle online CPUs.
In contrast, SRCU can have non-idle online CPUs that are completely
uninvolved in a given SRCU grace period, for example, a CPU that
never runs any SRCU read-side critical sections and took no part in
the grace-period processing. It is in theory possible for a given
synchronize_srcu()'s wakeup to be delivered to a CPU that was completely
uninvolved in the prior SRCU grace period, which could mean that the
code following that synchronize_srcu() would end up being unordered with
respect to both the grace period and any pre-existing SRCU read-side
critical sections.
This commit therefore adds an smp_mb() to the end of __synchronize_srcu(),
which prevents this scenario from occurring.
Reported-by: Lance Roy <ldr709@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Lance Roy <ldr709@gmail.com>
Cc: <stable@vger.kernel.org> # 4.12.x
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
After adopting callbacks from a newly offlined CPU, the adopting CPU
checks to make sure that its callback list's count is zero only if the
list has no callbacks and vice versa. Unfortunately, it does so after
enabling interrupts, which means that false positives are possible due to
interrupt handlers invoking call_rcu(). Although these false positives
are improbable, rcutorture did make it happen once.
This commit therefore moves this check to an irq-disabled region of code,
thus suppressing the false positive.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
Given changes to callback migration, rcu_cblist_head(),
rcu_cblist_tail(), rcu_cblist_count_cbs(), rcu_segcblist_segempty(),
rcu_segcblist_dequeued_lazy(), and rcu_segcblist_new_cbs() are
no longer used. This commit therefore removes them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
Given that the rcu_state structure's >orphan_pend and ->orphan_done
fields are used only during migration of callbacks from the recently
offlined CPU to a surviving CPU, if rcu_send_cbs_to_orphanage() and
rcu_adopt_orphan_cbs() are combined, these fields can become local
variables in the combined function. This commit therefore combines
rcu_send_cbs_to_orphanage() and rcu_adopt_orphan_cbs() into a new
rcu_segcblist_merge() function and removes the ->orphan_pend and
->orphan_done fields.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
When migrating callbacks from a newly offlined CPU, we are already
holding the root rcu_node structure's lock, so it costs almost nothing
to advance and accelerate the newly migrated callbacks. This patch
therefore makes this advancing and acceleration happen.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
The ->orphan_lock is acquired and released only within the
rcu_migrate_callbacks() function, which now acquires the root rcu_node
structure's ->lock. This commit therefore eliminates the ->orphan_lock
in favor of the root rcu_node structure's ->lock.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
It is possible that the outgoing CPU is unaware of recent grace periods,
and so it is also possible that some of its pending callbacks are actually
ready to be invoked. The current callback-migration code would needlessly
force these callbacks to pass through another grace period. This commit
therefore invokes rcu_advance_cbs() on the outgoing CPU's callbacks in
order to give them full credit for having passed through any recent
grace periods.
This also fixes an odd theoretical bug where there are no callbacks in
the system except for those on the outgoing CPU, none of those callbacks
have yet been associated with a grace-period number, there is never again
another callback registered, and the surviving CPU never again takes a
scheduling-clock interrupt, never goes idle, and never enters nohz_full
userspace execution. Yes, this is (just barely) possible. It requires
that the surviving CPU be a nohz_full CPU, that its scheduler-clock
interrupt be shut off, and that it loop forever in the kernel. You get
bonus points if you can make this one happen! ;-)
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:32 +07:00
RCU's CPU-hotplug callback-migration code first moves the outgoing
CPU's callbacks to ->orphan_done and ->orphan_pend, and only then
moves them to the NOCB callback list. This commit avoids the
extra step (and simplifies the code) by moving the callbacks directly
from the outgoing CPU's callback list to the NOCB callback list.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:31 +07:00
The current CPU-hotplug RCU-callback-migration code checks
for the source (newly offlined) CPU being a NOCBs CPU down in
rcu_send_cbs_to_orphanage(). This commit simplifies callback migration a
bit by moving this check up to rcu_migrate_callbacks(). This commit also
adds a check for the source CPU having no callbacks, which eases analysis
of the rcu_send_cbs_to_orphanage() and rcu_adopt_orphan_cbs() functions.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:31 +07:00
The rcu_node structure's ->n_cbs_orphaned and ->n_cbs_adopted fields
are updated, but never read. This commit therefore removes them.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:31 +07:00
The update of the ->expmaskinitnext and of ->ncpus are unsynchronized,
with the value of ->ncpus being incremented long before the corresponding
->expmaskinitnext mask is updated. If an RCU expedited grace period
sees ->ncpus change, it will update the ->expmaskinit masks from the new
->expmaskinitnext masks. But it is possible that ->ncpus has already
been updated, but the ->expmaskinitnext masks still have their old values.
For the current expedited grace period, no harm done. The CPU could not
have been online before the grace period started, so there is no need to
wait for its non-existent pre-existing readers.
But the next RCU expedited grace period is in a world of hurt. The value
of ->ncpus has already been updated, so this grace period will assume
that the ->expmaskinitnext masks have not changed. But they have, and
they won't be taken into account until the next never-been-online CPU
comes online. This means that RCU will be ignoring some CPUs that it
should be paying attention to.
The solution is to update ->ncpus and ->expmaskinitnext while holding
the ->lock for the rcu_node structure containing the ->expmaskinitnext
mask. Because smp_store_release() is now used to update ->ncpus and
smp_load_acquire() is now used to locklessly read it, if the expedited
grace period sees ->ncpus change, then the updating CPU has to
already be holding the corresponding ->lock. Therefore, when the
expedited grace period later acquires that ->lock, it is guaranteed
to see the new value of ->expmaskinitnext.
On the other hand, if the expedited grace period loads ->ncpus just
before an update, earlier full memory barriers guarantee that
the incoming CPU isn't far enough along to be running any RCU readers.
This commit therefore makes the required change.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:31 +07:00
RCU callbacks must be migrated away from an outgoing CPU, and this is
done near the end of the CPU-hotplug operation, after the outgoing CPU is
long gone. Unfortunately, this means that other CPU-hotplug callbacks
can execute while the outgoing CPU's callbacks are still immobilized
on the long-gone CPU's callback lists. If any of these CPU-hotplug
callbacks must wait, either directly or indirectly, for the invocation
of any of the immobilized RCU callbacks, the system will hang.
This commit avoids such hangs by migrating the callbacks away from the
outgoing CPU immediately upon its departure, shortly after the return
from __cpu_die() in takedown_cpu(). Thus, RCU is able to advance these
callbacks and invoke them, which allows all the after-the-fact CPU-hotplug
callbacks to wait on these RCU callbacks without risk of a hang.
While in the neighborhood, this commit also moves rcu_send_cbs_to_orphanage()
and rcu_adopt_orphan_cbs() under a pre-existing #ifdef to avoid including
dead code on the one hand and to avoid define-without-use warnings on the
other hand.
Reported-by: Jeffrey Hugo <jhugo@codeaurora.org>
Link: http://lkml.kernel.org/r/db9c91f6-1b17-6136-84f0-03c3c2581ab4@codeaurora.org
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Anna-Maria Gleixner <anna-maria@linutronix.de>
Cc: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: Richard Weinberger <richard@nod.at>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:31 +07:00
RCU's expedited grace periods can participate in out-of-memory deadlocks
due to all available system_wq kthreads being blocked and there not being
memory available to create more. This commit prevents such deadlocks
by allocating an RCU-specific workqueue_struct at early boot time, and
providing it with a rescuer to ensure forward progress. This uses the
shiny new init_rescuer() function provided by Tejun (but indirectly).
This commit also causes SRCU to use this new RCU-specific
workqueue_struct. Note that SRCU's use of workqueues never blocks them
waiting for readers, so this should be safe from a forward-progress
viewpoint. Note that this moves SRCU from system_power_efficient_wq
to a normal workqueue. In the unlikely event that this results in
measurable degradation, a separate power-efficient workqueue will be
creates for SRCU.
Change-Id: I2988819b553b769ccfdeabd62394c3aad63d6668
Reported-by: Prateek Sood <prsood@codeaurora.org>
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Tejun Heo <tj@kernel.org>
Git-commit: ad7c946b35ad455417fdd4bc0e17deda4011841b
Git-Repo: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: mydongistiny <jaysonedson@gmail.com>
Signed-off-by: DennySPB <dennyspb@gmail.com>
Signed-off-by: Twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:31 +07:00
There is some confusion as to which of cond_resched() or
cond_resched_rcu_qs() should be added to long in-kernel loops.
This commit therefore eliminates the decision by adding RCU quiescent
states to cond_resched(). This commit also simplifies the code that
used to interact with cond_resched_rcu_qs(), and that now interacts with
cond_resched(), to reduce its overhead. This reduction is necessary to
allow the heavier-weight cond_resched_rcu_qs() mechanism to be invoked
everywhere that cond_resched() is invoked.
Part of that reduction in overhead converts the jiffies_till_sched_qs
kernel parameter to read-only at runtime, thus eliminating the need for
bounds checking.
Reported-by: Michal Hocko <mhocko@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
[ paulmck: Keep PREEMPT=n cond_resched a no-op, per Peter Zijlstra. ]
Signed-off-by: mydongistiny <jaysonedson@gmail.com>
Signed-off-by: DennySPB <dennyspb@gmail.com>
Signed-off-by: twisted <36546624+TwistedPrime@users.noreply.github.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Paul E. McKenneyauthored and Sorayukiicommited 2026-05-15 17:49:30 +07:00
Commits started from ("rcu: Tighten up __call_rcu() rcu_head alignment check") and ended in ("rcutorture: Invoke call_rcu() from timer handler")
Signed-off-by: Yousef Algadri <yusufgadrie@gmail.com>
Signed-off-by: TsingPeng <tsingpeng@foxmail.com>
Signed-off-by: Sorayukii <sorayukii69@gmail.com>
Yousef Algadriauthored and Sorayukiicommited 2026-05-15 17:49:30 +07:00
* refs/heads/tmp-719bdd9:
Linux 4.9.180
drm: Wake up next in drm_read() chain if we are forced to putback the event
ASoC: davinci-mcasp: Fix clang warning without CONFIG_PM
spi: Fix zero length xfer bug
spi: rspi: Fix sequencer reset during initialization
spi : spi-topcliff-pch: Fix to handle empty DMA buffers
scsi: lpfc: Fix SLI3 commands being issued on SLI4 devices
media: saa7146: avoid high stack usage with clang
scsi: lpfc: Fix FDMI manufacturer attribute value
media: go7007: avoid clang frame overflow warning with KASAN
media: m88ds3103: serialize reset messages in m88ds3103_set_frontend
dmaengine: tegra210-adma: use devm_clk_*() helpers
scsi: qla4xxx: avoid freeing unallocated dma memory
usb: core: Add PM runtime calls to usb_hcd_platform_shutdown
rcuperf: Fix cleanup path for invalid perf_type strings
rcutorture: Fix cleanup path for invalid torture_type strings
x86/mce: Fix machine_check_poll() tests for error types
tty: ipwireless: fix missing checks for ioremap
virtio_console: initialize vtermno value for ports
media: wl128x: prevent two potential buffer overflows
spi: tegra114: reset controller on probe
cxgb3/l2t: Fix undefined behaviour
ASoC: fsl_utils: fix a leaked reference by adding missing of_node_put
ASoC: eukrea-tlv320: fix a leaked reference by adding missing of_node_put
HID: core: move Usage Page concatenation to Main item
chardev: add additional check for minor range overlap
x86/ia32: Fix ia32_restore_sigcontext() AC leak
x86/uaccess, signal: Fix AC=1 bloat
arm64: cpu_ops: fix a leaked reference by adding missing of_node_put
scsi: ufs: Avoid configuring regulator with undefined voltage range
scsi: ufs: Fix regulator load and icc-level configuration
brcmfmac: fix Oops when bringing up interface during USB disconnect
brcmfmac: fix race during disconnect when USB completion is in progress
brcmfmac: convert dev_init_lock mutex to completion
b43: shut up clang -Wuninitialized variable warning
brcmfmac: fix missing checks for kmemdup
mwifiex: Fix mem leak in mwifiex_tm_cmd
rtlwifi: fix a potential NULL pointer dereference
iio: common: ssp_sensors: Initialize calculated_time in ssp_common_process_data
iio: hmc5843: fix potential NULL pointer dereferences
iio: ad_sigma_delta: Properly handle SPI bus locking vs CS assertion
x86/build: Keep local relocations with ld.lld
cpufreq: pmac32: fix possible object reference leak
cpufreq/pasemi: fix possible object reference leak
cpufreq: ppc_cbe: fix possible object reference leak
s390: cio: fix cio_irb declaration
extcon: arizona: Disable mic detect if running when driver is removed
PM / core: Propagate dev->power.wakeup_path when no callbacks
mmc: sdhci-of-esdhc: add erratum eSDHC-A001 and A-008358 support
mmc: sdhci-of-esdhc: add erratum eSDHC5 support
mmc_spi: add a status check for spi_sync_locked
mmc: core: make pwrseq_emmc (partially) support sleepy GPIO controllers
scsi: libsas: Do discovery on empty PHY to update PHY info
hwmon: (f71805f) Use request_muxed_region for Super-IO accesses
hwmon: (pc87427) Use request_muxed_region for Super-IO accesses
hwmon: (smsc47b397) Use request_muxed_region for Super-IO accesses
hwmon: (smsc47m1) Use request_muxed_region for Super-IO accesses
hwmon: (vt1211) Use request_muxed_region for Super-IO accesses
RDMA/cxgb4: Fix null pointer dereference on alloc_skb failure
arm64: vdso: Fix clock_getres() for CLOCK_REALTIME
i40e: don't allow changes to HW VLAN stripping on active port VLANs
x86/irq/64: Limit IST stack overflow check to #DB stack
USB: core: Don't unbind interfaces following device reset failure
sched/core: Handle overflow in cpu_shares_write_u64
sched/core: Check quota and period overflow at usec to nsec conversion
powerpc/numa: improve control of topology updates
media: pvrusb2: Prevent a buffer overflow
media: au0828: Fix NULL pointer dereference in au0828_analog_stream_enable()
audit: fix a memory leak bug
media: ov2659: make S_FMT succeed even if requested format doesn't match
media: au0828: stop video streaming only when last user stops
media: ov6650: Move v4l2_clk_get() to ov6650_video_probe() helper
media: coda: clear error return value before picture run
dmaengine: at_xdmac: remove BUG_ON macro in tasklet
pinctrl: pistachio: fix leaked of_node references
HID: logitech-hidpp: use RAP instead of FAP to get the protocol version
mm/uaccess: Use 'unsigned long' to placate UBSAN warnings on older GCC versions
x86/mm: Remove in_nmi() warning from 64-bit implementation of vmalloc_fault()
smpboot: Place the __percpu annotation correctly
x86/build: Move _etext to actual end of .text
bcache: avoid clang -Wunintialized warning
bcache: add failure check to run_cache_set() for journal replay
bcache: fix failure in journal relplay
bcache: return error immediately in bch_journal_replay()
crypto: sun4i-ss - Fix invalid calculation of hash end
net: cw1200: fix a NULL pointer dereference
mwifiex: prevent an array overflow
ASoC: fsl_sai: Update is_slave_mode with correct value
mac80211/cfg80211: update bss channel on channel switch
dmaengine: pl330: _stop: clear interrupt status
w1: fix the resume command API
rtc: 88pm860x: prevent use-after-free on device remove
iwlwifi: pcie: don't crash on invalid RX interrupt
scsi: qla2xxx: Fix a qla24xx_enable_msix() error path
sched/cpufreq: Fix kobject memleak
arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable
ARM: vdso: Remove dependency with the arch_timer driver internals
brcm80211: potential NULL dereference in brcmf_cfg80211_vndr_cmds_dcmd_handler()
spi: pxa2xx: fix SCR (divisor) calculation
ASoC: imx: fix fiq dependencies
powerpc/boot: Fix missing check of lseek() return value
ASoC: hdmi-codec: unlock the device on startup errors
net: ena: gcc 8: fix compilation warning
dmaengine: tegra210-dma: free dma controller in remove()
mmc: core: Verify SD bus width
cxgb4: Fix error path in cxgb4_init_module
gfs2: Fix lru_count going negative
Revert "btrfs: Honour FITRIM range constraints during free space trim"
tools include: Adopt linux/bits.h
perf tools: No need to include bitops.h in util.h
at76c50x-usb: Don't register led_trigger if usb_register_driver failed
ssb: Fix possible NULL pointer dereference in ssb_host_pcmcia_exit
media: vivid: use vfree() instead of kfree() for dev->bitmap_cap
media: cpia2: Fix use-after-free in cpia2_exit
fbdev: fix WARNING in __alloc_pages_nodemask bug
hugetlb: use same fault hash key for shared and private mappings
fbdev: fix divide error in fb_var_to_videomode
btrfs: sysfs: don't leak memory when failing add fsid
Btrfs: fix race between ranged fsync and writeback of adjacent ranges
Btrfs: do not abort transaction at btrfs_update_root() after failure to COW path
gfs2: Fix sign extension bug in gfs2_update_stats
arm64: Save and restore OSDLR_EL1 across suspend/resume
libnvdimm/namespace: Fix label tracking error
kvm: svm/avic: fix off-by-one in checking host APIC ID
crypto: vmx - CTR: always increment IV as quadword
Revert "scsi: sd: Keep disk read-only when re-reading partition"
bio: fix improper use of smp_mb__before_atomic()
KVM: x86: fix return value for reserved EFER
ext4: do not delete unlinked inode from orphan list on failed truncate
f2fs: link f2fs quota ops for sysfile
Change-Id: Ief4e371f7f2377222f54fea237408c8bd5dda548
Signed-off-by: jianzhou <jianzhou@codeaurora.org>
[ Upstream commit ad092c027713a68a34168942a5ef422e42e039f4 ]
If the specified rcuperf.perf_type is not in the rcu_perf_init()
function's perf_ops[] array, rcuperf prints some console messages and
then invokes rcu_perf_cleanup() to set state so that a future torture
test can run. However, rcu_perf_cleanup() also attempts to end the
test that didn't actually start, and in doing so relies on the value
of cur_ops, a value that is not particularly relevant in this case.
This can result in confusing output or even follow-on failures due to
attempts to use facilities that have not been properly initialized.
This commit therefore sets the value of cur_ops to NULL in this case and
inserts a check near the beginning of rcu_perf_cleanup(), thus avoiding
relying on an irrelevant cur_ops value.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Paul E. McKenneyauthored and Greg Kroah-Hartmancommited 2019-05-31 06:48:30 -07:00
[ Upstream commit b813afae7ab6a5e91b4e16cc567331d9c2ae1f04 ]
If the specified rcutorture.torture_type is not in the rcu_torture_init()
function's torture_ops[] array, rcutorture prints some console messages
and then invokes rcu_torture_cleanup() to set state so that a future
torture test can run. However, rcu_torture_cleanup() also attempts to
end the test that didn't actually start, and in doing so relies on the
value of cur_ops, a value that is not particularly relevant in this case.
This can result in confusing output or even follow-on failures due to
attempts to use facilities that have not been properly initialized.
This commit therefore sets the value of cur_ops to NULL in this case
and inserts a check near the beginning of rcu_torture_cleanup(),
thus avoiding relying on an irrelevant cur_ops value.
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Paul E. McKenneyauthored and Greg Kroah-Hartmancommited 2019-05-31 06:48:30 -07:00
* refs/heads/tmp-72b54df:
Linux 4.9.165
KVM: X86: Fix residual mmio emulation request to userspace
KVM: nVMX: Ignore limit checks on VMX instructions using flat segments
KVM: nVMX: Sign extend displacements of VMX instr's mem operands
drm/radeon/evergreen_cs: fix missing break in switch statement
media: uvcvideo: Avoid NULL pointer dereference at the end of streaming
rcu: Do RCU GP kthread self-wakeup from softirq and interrupt
md: Fix failed allocation of md_register_thread
perf intel-pt: Fix divide by zero when TSC is not available
perf intel-pt: Fix overlap calculation for padding
perf auxtrace: Define auxtrace record alignment
perf intel-pt: Fix CYC timestamp calculation after OVF
bcache: never writeback a discard operation
PM / wakeup: Rework wakeup source timer cancellation
nfsd: fix wrong check in write_v4_end_grace()
nfsd: fix memory corruption caused by readdir
NFS: Don't recoalesce on error in nfs_pageio_complete_mirror()
NFS: Fix an I/O request leakage in nfs_do_recoalesce
NFS: Fix I/O request leakages
dm: fix to_sector() for 32bit
ARM: s3c24xx: Fix boolean expressions in osiris_dvs_notify
powerpc/ptrace: Simplify vr_get/set() to avoid GCC warning
powerpc: Fix 32-bit KVM-PR lockup and host crash with MacOS guest
powerpc/83xx: Also save/restore SPRG4-7 during suspend
powerpc/powernv: Make opal log only readable by root
powerpc/wii: properly disable use of BATs when requested.
powerpc/32: Clear on-stack exception marker upon exception return
jbd2: fix compile warning when using JBUFFER_TRACE
jbd2: clear dirty flag when revoking a buffer from an older transaction
serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()
serial: 8250_pci: Fix number of ports for ACCES serial cards
8250: FIX Fourth port offset of Pericom PI7C9X7954 boards
serial: 8250_of: assume reg-shift of 2 for mrvl,mmp-uart
serial: uartps: Fix stuck ISR if RX disabled with non-empty FIFO
drm/i915: Relax mmap VMA check
i2c: tegra: fix maximum transfer size
parport_pc: fix find_superio io compare code, should use equal test.
intel_th: Don't reference unassigned outputs
device property: Fix the length used in PROPERTY_ENTRY_STRING()
kernel/sysctl.c: add missing range check in do_proc_dointvec_minmax_conv
mm/vmalloc: fix size check for remap_vmalloc_range_partial()
mm: hwpoison: fix thp split handing in soft_offline_in_use_page()
nfit: acpi_nfit_ctl(): Check out_obj->type in the right place
clk: ingenic: Fix doc of ingenic_cgu_div_info
clk: ingenic: Fix round_rate misbehaving with non-integer dividers
clk: clk-twl6040: Fix imprecise external abort for pdmclk
ext2: Fix underflow in ext2_max_size()
ext4: fix crash during online resizing
cpufreq: pxa2xx: remove incorrect __init annotation
cpufreq: tegra124: add missing of_node_put()
libertas_tf: don't set URB_ZERO_PACKET on IN USB transfer
crypto: pcbc - remove bogus memcpy()s with src == dest
Btrfs: fix corruption reading shared and compressed extents after hole punching
btrfs: ensure that a DUP or RAID1 block group has exactly two stripes
m68k: Add -ffreestanding to CFLAGS
splice: don't merge into linked buffers
fs/devpts: always delete dcache dentry-s in dput()
scsi: target/iscsi: Avoid iscsit_release_commands_from_conn() deadlock
scsi: sd: Optimal I/O size should be a multiple of physical block size
scsi: virtio_scsi: don't send sc payload with tmfs
s390/virtio: handle find on invalid queue gracefully
clocksource/drivers/exynos_mct: Clear timer interrupt when shutdown
clocksource/drivers/exynos_mct: Move one-shot check from tick clear to ISR
regulator: s2mpa01: Fix step values for some LDOs
regulator: s2mps11: Fix steps for buck7, buck8 and LDO35
spi: pxa2xx: Setup maximum supported DMA transfer length
spi: ti-qspi: Fix mmap read when more than one CS in use
ACPI / device_sysfs: Avoid OF modalias creation for removed device
tracing: Do not free iter->trace in fail path of tracing_open_pipe()
tracing: Use strncpy instead of memcpy for string keys in hist triggers
CIFS: Fix read after write for files with read caching
CIFS: Do not reset lease state to NONE on lease break
crypto: arm64/aes-ccm - fix logical bug in AAD MAC handling
crypto: hash - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
libnvdimm: Fix altmap reservation size calculation
libnvdimm/pmem: Honor force_raw for legacy pmem regions
libnvdimm/label: Clear 'updating' flag after label-set update
stm class: Prevent division by zero
tmpfs: fix uninitialized return value in shmem_link
net: set static variable an initial value in atl2_probe()
nfp: bpf: fix ALU32 high bits clearance bug
nfp: bpf: fix code-gen bug on BPF_ALU | BPF_XOR | BPF_K
net: thunderx: make CFG_DONE message to run through generic send-ack sequence
mac80211_hwsim: propagate genlmsg_reply return code
phonet: fix building with clang
ARC: uacces: remove lp_start, lp_end from clobber list
ARCv2: lib: memcpy: fix doing prefetchw outside of buffer
tmpfs: fix link accounting when a tmpfile is linked in
net: marvell: mvneta: fix DMA debug warning
arm64: Relax GIC version check during early boot
ASoC: topology: free created components in tplg load error
net: mv643xx_eth: disable clk on error path in mv643xx_eth_shared_probe()
qmi_wwan: apply SET_DTR quirk to Sierra WP7607
pinctrl: meson: meson8b: fix the sdxc_a data 1..3 pins
net: systemport: Fix reception of BPDUs
scsi: libiscsi: Fix race between iscsi_xmit_task and iscsi_complete_task
assoc_array: Fix shortcut creation
ARM: 8824/1: fix a migrating irq bug when hotplug cpu
clk: sunxi: A31: Fix wrong AHB gate number
Input: st-keyscan - fix potential zalloc NULL dereference
i2c: cadence: Fix the hold bit setting
net: hns: Fix object reference leaks in hns_dsaf_roce_reset()
mm: page_alloc: fix ref bias in page_frag_alloc() for 1-byte allocs
mm/gup: fix gup_pmd_range() for dax
floppy: check_events callback should not return a negative number
Input: matrix_keypad - use flush_delayed_work()
Input: cap11xx - switch to using set_brightness_blocking()
ARM: OMAP2+: Variable "reg" in function omap4_dsi_mux_pads() could be uninitialized
s390/dasd: fix using offset into zero size array error
gpu: ipu-v3: Fix CSI offsets for imx53
gpu: ipu-v3: Fix i.MX51 CSI control registers offset
crypto: ahash - fix another early termination in hash walk
crypto: caam - fixed handling of sg list
stm class: Fix an endless loop in channel allocation
iio: adc: exynos-adc: Fix NULL pointer exception on unbind
ASoC: fsl_esai: fix register setting issue in RIGHT_J mode
9p/net: fix memory leak in p9_client_create
9p: use inode->i_lock to protect i_size_write() under 32-bit
media: videobuf2-v4l2: drop WARN_ON in vb2_warn_zero_bytesused()
FROMLIST: psi: introduce psi monitor
FROMLIST: refactor header includes to allow kthread.h inclusion in psi_types.h
FROMLIST: psi: track changed states
FROMLIST: psi: split update_stats into parts
FROMLIST: psi: rename psi fields in preparation for psi trigger addition
FROMLIST: psi: make psi_enable static
FROMLIST: psi: introduce state_mask to represent stalled psi states
ANDROID: cuttlefish_defconfig: Enable CONFIG_PSI
BACKPORT: kernel: cgroup: add poll file operation
BACKPORT: fs: kernfs: add poll file operation
UPSTREAM: psi: avoid divide-by-zero crash inside virtual machines
UPSTREAM: psi: clarify the Kconfig text for the default-disable option
UPSTREAM: psi: fix aggregation idle shut-off
UPSTREAM: cgroup add cftype->open/release() callbacks
UPSTREAM: kernfs: Check KERNFS_HAS_RELEASE before calling kernfs_release_file()
UPSTREAM: kernfs: fix locking around kernfs_ops->release() callback
UPSTREAM: kernfs: add kernfs_ops->open/release() callbacks
UPSTREAM: psi: fix reference to kernel commandline enable
BACKPORT: psi: make disabling/enabling easier for vendor kernels
UPSTREAM: kernel/sched/psi.c: simplify cgroup_move_task()
BACKPORT: psi: cgroup support
UPSTREAM: psi: pressure stall information for CPU, memory, and IO
BACKPORT: sched: introduce this_rq_lock_irq()
BACKPORT: sched: sched.h: make rq locking and clock functions available in stats.h
UPSTREAM: sched: loadavg: make calc_load_n() public
UPSTREAM: sched: loadavg: consolidate LOAD_INT, LOAD_FRAC, CALC_LOAD
BACKPORT: delayacct: track delays from thrashing cache pages
BACKPORT: mm: workingset: tell cache transitions from workingset thrashing
BACKPORT: cgroup: misc changes
UPSTREAM: sched/headers: Remove <linux/sched.h> from <linux/sched/loadavg.h>
UPSTREAM: sched/headers: Move loadavg related definitions from <linux/sched.h> to <linux/sched/loadavg.h>
UPSTREAM: sched/headers, delayacct: Move the 'struct task_delay_info' definition from <linux/sched.h> to <linux/delayacct.h>
UPSTREAM: sched/headers: Prepare for new header dependencies before moving code to <linux/sched/loadavg.h>
BACKPORT: sched/core: Add wrappers for lockdep_(un)pin_lock()
UPSTREAM: Avoid page waitqueue race leaving possible page locker waiting
UPSTREAM: mm: add PageWaiters indicating tasks are waiting for a page bit
UPSTREAM: workqueue: make workqueue available early during boot
ANDROID: ion_dummy_driver: Remove SYSTEM_CONTIG heap
ANDROID: ion_dummy_driver: Rework ion_dummy_driver to avoid direct indexing into the heaps
ANDROID: ion_dummy_driver: Use IS_ERR_OR_NULL() before destroying heaps
ANDROID: sched/fair: fix energy compute when a cluster is only a cpu core in multi-cluster system
Conflicts:
arch/arm/kernel/irq.c
drivers/scsi/sd.c
include/linux/cgroup.h
include/linux/sched.h
kernel/sched/Makefile
kernel/sched/core.c
mm/page_alloc.c
Change-Id: I387345d8f6d2145e2456fbead266c897475dfb4c
Signed-off-by: jianzhou <jianzhou@codeaurora.org>
commit 1d1f898df6586c5ea9aeaf349f13089c6fa37903 upstream.
The rcu_gp_kthread_wake() function is invoked when it might be necessary
to wake the RCU grace-period kthread. Because self-wakeups are normally
a useless waste of CPU cycles, if rcu_gp_kthread_wake() is invoked from
this kthread, it naturally refuses to do the wakeup.
Unfortunately, natural though it might be, this heuristic fails when
rcu_gp_kthread_wake() is invoked from an interrupt or softirq handler
that interrupted the grace-period kthread just after the final check of
the wait-event condition but just before the schedule() call. In this
case, a wakeup is required, even though the call to rcu_gp_kthread_wake()
is within the RCU grace-period kthread's context. Failing to provide
this wakeup can result in grace periods failing to start, which in turn
results in out-of-memory conditions.
This race window is quite narrow, but it actually did happen during real
testing. It would of course need to be fixed even if it was strictly
theoretical in nature.
This patch does not Cc stable because it does not apply cleanly to
earlier kernel versions.
Fixes: 48a7639ce8 ("rcu: Make callers awaken grace-period kthread")
Reported-by: "He, Bo" <bo.he@intel.com>
Co-developed-by: "Zhang, Jun" <jun.zhang@intel.com>
Co-developed-by: "He, Bo" <bo.he@intel.com>
Co-developed-by: "xiao, jin" <jin.xiao@intel.com>
Co-developed-by: Bai, Jie A <jie.a.bai@intel.com>
Signed-off: "Zhang, Jun" <jun.zhang@intel.com>
Signed-off: "He, Bo" <bo.he@intel.com>
Signed-off: "xiao, jin" <jin.xiao@intel.com>
Signed-off: Bai, Jie A <jie.a.bai@intel.com>
Signed-off-by: "Zhang, Jun" <jun.zhang@intel.com>
[ paulmck: Switch from !in_softirq() to "!in_interrupt() &&
!in_serving_softirq() to avoid redundant wakeups and to also handle the
interrupt-handler scenario as well as the softirq-handler scenario that
actually occurred in testing. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Link: https://lkml.kernel.org/r/CD6925E8781EFD4D8E11882D20FC406D52A11F61@SHSMSX104.ccr.corp.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Zhang, Junauthored and Greg Kroah-Hartmancommited 2019-03-23 13:19:53 +01:00
* refs/heads/tmp-859e0a8:
Linux 4.9.105
Revert "vti4: Don't override MTU passed on link creation via IFLA_MTU"
Revert "vti4: Don't override MTU passed on link creation via IFLA_MTU"
Linux 4.9.104
kdb: make "mdr" command repeat
pinctrl: msm: Use dynamic GPIO numbering
regulator: of: Add a missing 'of_node_put()' in an error handling path of 'of_regulator_match()'
ARM: dts: porter: Fix HDMI output routing
ARM: dts: imx7d: cl-som-imx7: fix pinctrl_enet
regmap: Correct comparison in regmap_cached
netlabel: If PF_INET6, check sk_buff ip header version
selftests/net: fixes psock_fanout eBPF test case
perf report: Fix memory corruption in --branch-history mode --branch-history
perf tests: Use arch__compare_symbol_names to compare symbols
x86/apic: Set up through-local-APIC mode on the boot CPU if 'noapic' specified
drm/rockchip: Respect page offset for PRIME mmap calls
MIPS: Octeon: Fix logging messages with spurious periods after newlines
pinctrl: sh-pfc: r8a7796: Fix MOD_SEL register pin assignment for SSI pins group
rcu: Call touch_nmi_watchdog() while printing stall warnings
audit: return on memory error to avoid null pointer dereference
ARM: dts: bcm283x: Fix probing of bcm2835-i2s
udf: Provide saner default for invalid uid / gid
PCI: Add function 1 DMA alias quirk for Marvell 88SE9220
cpufreq: Reorder cpufreq_online() error code path
net: stmmac: ensure that the MSS desc is the last desc to set the own bit
net: stmmac: ensure that the device has released ownership before reading data
dmaengine: qcom: bam_dma: get num-channels and num-ees from dt
hwrng: stm32 - add reset during probe
enic: enable rq before updating rq descriptors
dmaengine: rcar-dmac: Check the done lists in rcar_dmac_chan_get_residue()
dmaengine: pl330: fix a race condition in case of threaded irqs
ALSA: vmaster: Propagate slave error
x86/devicetree: Fix device IRQ settings in DT
x86/devicetree: Initialize device tree before using it
gfs2: Fix fallocate chunk size
soc: qcom: wcnss_ctrl: Fix increment in NV upload
arm64: dts: qcom: Fix SPI5 config on MSM8996
perf/x86/intel: Fix event update for auto-reload
perf/x86/intel: Fix large period handling on Broadwell CPUs
cdrom: do not call check_disk_change() inside cdrom_open()
perf/x86/intel: Properly save/restore the PMU state in the NMI handler
hwmon: (pmbus/adm1275) Accept negative page register values
hwmon: (pmbus/max8688) Accept negative page register values
drm/panel: simple: Fix the bus format for the Ontat panel
perf/core: Fix perf_output_read_group()
f2fs: fix to check extent cache in f2fs_drop_extent_tree
powerpc: Add missing prototype for arch_irq_work_raise()
ipmi_ssif: Fix kernel panic at msg_done_handler
PCI: Restore config space on runtime resume despite being unbound
MIPS: ath79: Fix AR724X_PLL_REG_PCIE_CONFIG offset
spi: bcm-qspi: fIX some error handling paths
regulator: gpio: Fix some error handling paths in 'gpio_regulator_probe()'
IB/core: Honor port_num while resolving GID for IB link layer
perf stat: Fix core dump when flag T is used
perf top: Fix top.call-graph config option reading
KVM: lapic: stop advertising DIRECTED_EOI when in-kernel IOAPIC is in use
i2c: mv64xxx: Apply errata delay only in standard mode
cxgb4: Fix queue free path of ULD drivers
ACPICA: acpi: acpica: fix acpi operand cache leak in nseval.c
ACPICA: Events: add a return on failure from acpi_hw_register_read
bcache: quit dc->writeback_thread when BCACHE_DEV_DETACHING is set
zorro: Set up z->dev.dma_mask for the DMA API
cpufreq: cppc_cpufreq: Fix cppc_cpufreq_init() failure path
arm: dts: socfpga: fix GIC PPI warning
virtio-net: Fix operstate for virtio when no VIRTIO_NET_F_STATUS
ima: Fallback to the builtin hash algorithm
cxgb4: Setup FW queues before registering netdev
ath10k: Fix kernel panic while using worker (ath10k_sta_rc_update_wk)
net/mlx5: Protect from command bit overflow
selftests: Print the test we're running to /dev/kmsg
tools/thermal: tmon: fix for segfault
powerpc/perf: Fix kernel address leak via sampling registers
powerpc/perf: Prevent kernel address leak to userspace via BHRB buffer
hwmon: (nct6775) Fix writing pwmX_mode
parisc/pci: Switch LBA PCI bus from Hard Fail to Soft Fail mode
m68k: set dma and coherent masks for platform FEC ethernets
powerpc/mpic: Check if cpu_possible() in mpic_physmask()
ACPI: acpi_pad: Fix memory leak in power saving threads
drivers: macintosh: rack-meter: really fix bogus memsets
xen/acpi: off by one in read_acpi_id()
rxrpc: Don't treat call aborts as conn aborts
rxrpc: Fix Tx ring annotation after initial Tx failure
btrfs: fix lockdep splat in btrfs_alloc_subvolume_writers
Btrfs: fix copy_items() return value when logging an inode
btrfs: tests/qgroup: Fix wrong tree backref level
net: bgmac: Fix endian access in bgmac_dma_tx_ring_free()
sparc64: Make atomic_xchg() an inline function rather than a macro.
fscache: Fix hanging wait on page discarded by writeback
KVM: VMX: raise internal error for exception during invalid protected mode state
sched/rt: Fix rq->clock_update_flags < RQCF_ACT_SKIP warning
ocfs2/dlm: don't handle migrate lockres if already in shutdown
btrfs: Fix possible softlock on single core machines
Btrfs: fix NULL pointer dereference in log_dir_items
Btrfs: bail out on error during replay_dir_deletes
mm: fix races between address_space dereference and free in page_evicatable
mm/ksm: fix interaction with THP
dp83640: Ensure against premature access to PHY registers after reset
cpufreq: CPPC: Initialize shared perf capabilities of CPUs
Force log to disk before reading the AGF during a fstrim
sr: get/drop reference to device in revalidate and check_events
swap: divide-by-zero when zero length swap file on ssd
fs/proc/proc_sysctl.c: fix potential page fault while unregistering sysctl table
x86/mm: Do not forbid _PAGE_RW before init for __ro_after_init
x86/pgtable: Don't set huge PUD/PMD on non-leaf entries
nvme: don't send keep-alives to the discovery controller
sh: fix debug trap failure to process signals before return to user
net: mvneta: fix enable of all initialized RXQs
net: Fix untag for vlan packets without ethernet header
mm/kmemleak.c: wait for scan completion before disabling free
builddeb: Fix header package regarding dtc source links
llc: properly handle dev_queue_xmit() return value
perf/x86/intel: Fix linear IP of PEBS real_ip on Haswell and later CPUs
net: qmi_wwan: add BroadMobi BM806U 2020:2033
ARM: 8748/1: mm: Define vdso_start, vdso_end as array
batman-adv: fix packet loss for broadcasted DHCP packets to a server
batman-adv: fix multicast-via-unicast transmission with AP isolation
selftests: ftrace: Add a testcase for probepoint
selftests: ftrace: Add a testcase for string type with kprobe_event
selftests: ftrace: Add probe event argument syntax testcase
mm, thp: do not cause memcg oom for thp
mm/mempolicy.c: avoid use uninitialized preferred_node
RDMA/qedr: Fix rc initialization on CNQ allocation failure
RDMA/qedr: fix QP's ack timeout configuration
RDMA/ucma: Correct option size check using optlen
kbuild: make scripts/adjust_autoksyms.sh robust against timestamp races
brcmfmac: Fix check for ISO3166 code
perf/cgroup: Fix child event counting bug
vti4: Don't override MTU passed on link creation via IFLA_MTU
vti4: Don't count header length twice on tunnel setup
batman-adv: Fix skbuff rcsum on packet reroute
batman-adv: fix header size check in batadv_dbg_arp()
net: Fix vlan untag for bridge and vlan_dev with reorder_hdr off
drm/imx: move arming of the vblank event to atomic_flush
sunvnet: does not support GSO for sctp
ipv4: lock mtu in fnhe when received PMTU < net.ipv4.route.min_pmtu
workqueue: use put_device() instead of kfree()
bnxt_en: Check valid VNIC ID in bnxt_hwrm_vnic_set_tpa().
netfilter: ebtables: fix erroneous reject of last rule
dmaengine: mv_xor_v2: Fix clock resource by adding a register clock
arm64: Relax ARM_SMCCC_ARCH_WORKAROUND_1 discovery
xen: xenbus: use put_device() instead of kfree()
IB/core: Fix possible crash to access NULL netdev
net: smsc911x: Fix unload crash when link is up
net: qcom/emac: Use proper free methods during TX
fsl/fman: avoid sleeping in atomic context while adding an address
fbdev: Fixing arbitrary kernel leak in case FBIOGETCMAP_SPARC in sbusfb_ioctl_helper().
IB/mlx5: Fix an error code in __mlx5_ib_modify_qp()
IB/mlx4: Include GID type when deleting GIDs from HW table under RoCE
IB/mlx4: Fix corruption of RoCEv2 IPv4 GIDs
RDMA/qedr: Fix iWARP write and send with immediate
RDMA/qedr: Fix kernel panic when running fio over NFSoRDMA
ia64/err-inject: Use get_user_pages_fast()
e1000e: allocate ring descriptors with dma_zalloc_coherent
e1000e: Fix check_for_link return value with autoneg off
batman-adv: Fix multicast packet loss with a single WANT_ALL_IPV4/6 flag
watchdog: sbsa: use 32-bit read for WCV
watchdog: f71808e_wdt: Fix magic close handling
iwlwifi: mvm: fix TX of CCMP 256
KVM: PPC: Book3S HV: Fix VRMA initialization with 2MB or 1GB memory backing
selftests/powerpc: Skip the subpage_prot tests if the syscall is unavailable
Btrfs: send, fix issuing write op when processing hole in no data mode
drm/sun4i: Fix dclk_set_phase
xen/pirq: fix error path cleanup when binding MSIs
nvmet: fix PSDT field check in command format
net/tcp/illinois: replace broken algorithm reference link
gianfar: Fix Rx byte accounting for ndev stats
powerpc/boot: Fix random libfdt related build errors
ARM: dts: NSP: Fix amount of RAM on BCM958625HR
sit: fix IFLA_MTU ignored on NEWLINK
ip6_tunnel: fix IFLA_MTU ignored on NEWLINK
bcache: fix kcrashes with fio in RAID5 backend dev
dmaengine: rcar-dmac: fix max_chunk_size for R-Car Gen3
virtio-gpu: fix ioctl and expose the fixed status to userspace.
r8152: fix tx packets accounting
qrtr: add MODULE_ALIAS macro to smd
ARM: orion5x: Revert commit 4904dbda41.
ceph: fix dentry leak when failing to init debugfs
clocksource/drivers/fsl_ftm_timer: Fix error return checking
nvme-pci: Fix nvme queue cleanup if IRQ setup fails
batman-adv: Fix netlink dumping of BLA backbones
batman-adv: Fix netlink dumping of BLA claims
batman-adv: Ignore invalid batadv_v_gw during netlink send
batman-adv: Ignore invalid batadv_iv_gw during netlink send
netfilter: ebtables: convert BUG_ONs to WARN_ONs
batman-adv: invalidate checksum on fragment reassembly
batman-adv: fix packet checksum in receive path
md/raid1: fix NULL pointer dereference
md: fix a potential deadlock of raid5/raid10 reshape
fs: dcache: Use READ_ONCE when accessing i_dir_seq
fs: dcache: Avoid livelock between d_alloc_parallel and __d_add
kvm: fix warning for CONFIG_HAVE_KVM_EVENTFD builds
macvlan: fix use-after-free in macvlan_common_newlink()
arm64: fix unwind_frame() for filtered out fn for function graph tracing
mac80211: drop frames with unexpected DS bits from fast-rx to slow path
x86/topology: Update the 'cpu cores' field in /proc/cpuinfo correctly across CPU hotplug operations
locking/xchg/alpha: Fix xchg() and cmpxchg() memory ordering bugs
integrity/security: fix digsig.c build error with header file
regulatory: add NUL to request alpha2
smsc75xx: fix smsc75xx_set_features()
ARM: OMAP: Fix dmtimer init for omap1
PKCS#7: fix direct verification of SignerInfo signature
s390/cio: clear timer when terminating driver I/O
s390/cio: fix return code after missing interrupt
s390/cio: fix ccw_device_start_timeout API
powerpc/bpf/jit: Fix 32-bit JIT for seccomp_data access
kernel/relay.c: limit kmalloc size to KMALLOC_MAX_SIZE
md: raid5: avoid string overflow warning
locking/xchg/alpha: Add unconditional memory barrier to cmpxchg()
drm/exynos: fix comparison to bitshift when dealing with a mask
drm/exynos: g2d: use monotonic timestamps
md raid10: fix NULL deference in handle_write_completed()
mac80211: Do not disconnect on invalid operating class
mac80211: fix calling sleeping function in atomic context
mac80211: fix a possible leak of station stats
mac80211: round IEEE80211_TX_STATUS_HEADROOM up to multiple of 4
rxrpc: Work around usercopy check
NFC: llcp: Limit size of SDP URI
iwlwifi: mvm: always init rs with 20mhz bandwidth rates
iwlwifi: mvm: fix security bug in PN checking
ibmvnic: Free RX socket buffer in case of adapter error
ARM: OMAP1: clock: Fix debugfs_create_*() usage
ARM: OMAP3: Fix prm wake interrupt for resume
ARM: OMAP2+: timer: fix a kmemleak caused in omap_get_timer_dt
selftests: memfd: add config fragment for fuse
selftests: pstore: Adding config fragment CONFIG_PSTORE_RAM=m
libata: Fix compile warning with ATA_DEBUG enabled
ptr_ring: prevent integer overflow when calculating size
ARC: Fix malformed ARC_EMUL_UNALIGNED default
irqchip/gic-v3: Change pr_debug message to pr_devel
cpumask: Make for_each_cpu_wrap() available on UP as well
irqchip/gic-v3: Ignore disabled ITS nodes
locking/qspinlock: Ensure node->count is updated before initialising node
vfs/proc/kcore, x86/mm/kcore: Fix SMAP fault when dumping vsyscall user page
bpf: fix rlimit in reuseport net selftest
tools/libbpf: handle issues with bpf ELF objects containing .eh_frames
bcache: return attach error when no cache set exist
bcache: fix for data collapse after re-attaching an attached device
bcache: fix for allocator and register thread race
bcache: properly set task state in bch_writeback_thread()
cifs: silence compiler warnings showing up with gcc-8.0.0
proc: fix /proc/*/map_files lookup
arm64: spinlock: Fix theoretical trylock() A-B-A with LSE atomics
RDS: IB: Fix null pointer issue
xen/grant-table: Use put_page instead of free_page
xen-netfront: Fix race between device setup and open
MIPS: TXx9: use IS_BUILTIN() for CONFIG_LEDS_CLASS
MIPS: generic: Fix machine compatible matching
bpf: fix selftests/bpf test_kmod.sh failure when CONFIG_BPF_JIT_ALWAYS_ON=y
ACPI / scan: Use acpi_bus_get_status() to initialize ACPI_TYPE_DEVICE devs
ACPI: processor_perflib: Do not send _PPC change notification if not ready
firmware: dmi_scan: Fix handling of empty DMI strings
x86/power: Fix swsusp_arch_resume prototype
netfilter: ipv6: nf_defrag: Kill frag queue on RFC2460 failure
drm/nouveau/pmu/fuc: don't use movw directly anymore
IB/ipoib: Fix for potential no-carrier state
openvswitch: Remove padding from packet before L3+ conntrack processing
mm/fadvise: discard partial page if endbyte is also EOF
mm: pin address_space before dereferencing it while isolating an LRU page
mm: thp: use down_read_trylock() in khugepaged to avoid long block
sparc64: update pmdp_invalidate() to return old pmd value
asm-generic: provide generic_pmdp_establish()
mm/mempolicy: add nodes_empty check in SYSC_migrate_pages
mm/mempolicy: fix the check of nodemask from user
ocfs2: return error when we attempt to access a dirty bh in jbd2
ocfs2/acl: use 'ip_xattr_sem' to protect getting extended attribute
ocfs2: return -EROFS to mount.ocfs2 if inode block is invalid
kvm: Map PFN-type memory regions as writable (if possible)
tcp_nv: fix potential integer overflow in tcpnv_acked
gianfar: prevent integer wrapping in the rx handler
ntb_transport: Fix bug with max_mw_size parameter
RDMA/mlx5: Avoid memory leak in case of XRCD dealloc failure
powerpc/numa: Ensure nodes initialized for hotplug
powerpc/numa: Use ibm,max-associativity-domains to discover possible nodes
jffs2: Fix use-after-free bug in jffs2_iget()'s error handling path
device property: Define type of PROPERTY_ENRTY_*() macros
fm10k: fix "failed to kill vid" message for VF
HID: roccat: prevent an out of bounds read in kovaplus_profile_activated()
btrfs: fail mount when sb flag is not in BTRFS_SUPER_FLAG_SUPP
Btrfs: fix scrub to repair raid6 corruption
btrfs: Fix out of bounds access in btrfs_search_slot
Btrfs: set plug for fsync
ipmi/powernv: Fix error return code in ipmi_powernv_probe()
mac80211_hwsim: fix possible memory leak in hwsim_new_radio_nl()
kconfig: Fix expr_free() E_NOT leak
kconfig: Fix automatic menu creation mem leak
kconfig: Don't leak main menus during parsing
watchdog: sp5100_tco: Fix watchdog disable bit
nfs: Do not convert nfs_idmap_cache_timeout to jiffies
net: stmmac: dwmac-meson8b: propagate rate changes to the parent clock
net: stmmac: dwmac-meson8b: fix setting the RGMII TX clock on Meson8b
dm thin: fix documentation relative to low water mark threshold
iommu/vt-d: Use domain instead of cache fetching
perf record: Fix failed memory allocation for get_cpuid_str
tools lib traceevent: Fix get_field_str() for dynamic strings
perf callchain: Fix attr.sample_max_stack setting
tools lib traceevent: Simplify pointer print logic and fix %pF
i40iw: Zero-out consumer key on allocate stag for FMR
Input: psmouse - fix Synaptics detection when protocol is disabled
PCI: Add function 1 DMA alias quirk for Marvell 9128
tracing/hrtimer: Fix tracing bugs by taking all clock bases and modes into account
netfilter: ipv6: nf_defrag: Pass on packets to stack per RFC2460
kvm: x86: fix KVM_XEN_HVM_CONFIG ioctl
ALSA: hda - Use IS_REACHABLE() for dependency on input
NFSv4: always set NFS_LOCK_LOST when a lock is lost.
x86/tsc: Allow TSC calibration without PIT
firewire-ohci: work around oversized DMA reads on JMicron controllers
kvm: x86: IA32_ARCH_CAPABILITIES is always supported
KVM: x86: Update cpuid properly when CR4.OSXAVE or CR4.PKE is changed
KVM: s390: vsie: fix < 8k check for the itdba
KVM/VMX: Expose SSBD properly to guests
kernel/signal.c: avoid undefined behaviour in kill_something_info
kernel/sys.c: fix potential Spectre v1 issue
kasan: fix memory hotplug during boot
ipc/shm: fix shmat() nil address after round-down when remapping
Revert "ipc/shm: Fix shmat mmap nil-page protection"
IB/hfi1: Use after free race condition in send context error path
drm/vmwgfx: Fix 32-bit VMW_PORT_HB_[IN|OUT] macros
xen-swiotlb: fix the check condition for xen_swiotlb_free_coherent
libata: blacklist Micron 500IT SSD with MU01 firmware
libata: Blacklist some Sandisk SSDs for NCQ
mmc: sdhci-iproc: fix 32bit writes for TRANSFER_MODE register
mmc: sdhci-iproc: remove hard coded mmc cap 1.8v
do d_instantiate/unlock_new_inode combinations safely
ALSA: timer: Fix pause event notification
aio: fix io_destroy(2) vs. lookup_ioctx() race
affs_lookup(): close a race with affs_remove_link()
KVM: Fix spelling mistake: "cop_unsuable" -> "cop_unusable"
MIPS: Fix ptrace(2) PTRACE_PEEKUSR and PTRACE_POKEUSR accesses to o32 FGRs
MIPS: ptrace: Expose FIR register through FP regset
MIPS: c-r4k: Fix data corruption related to cache coherence
UPSTREAM: sched/fair: Consider RT/IRQ pressure in capacity_spare_wake
BACKPORT, FROMLIST: fscrypt: add Speck128/256 support
Conflicts:
fs/crypto/fscrypt_private.h
fs/crypto/keyinfo.c
include/uapi/linux/fs.h
Change-Id: I47c7c5551b887b4a109cceb04811fc6ccf98b5bc
Signed-off-by: Blagovest Kolenichev <bkolenichev@codeaurora.org>
[ Upstream commit 3caa973b7a260e7a2a69edc94c300ab9c65148c3 ]
When RCU stall warning triggers, it can print out a lot of messages
while holding spinlocks. If the console device is slow (e.g. an
actual or IPMI serial console), it may end up triggering NMI hard
lockup watchdog like the following.
Tejun Heoauthored and Greg Kroah-Hartmancommited 2018-05-30 07:50:50 +02:00
* 4.9/tmp-86f97ab:
Linux 4.9.57
KVM: nVMX: update last_nonleaf_level when initializing nested EPT
x86/alternatives: Fix alt_max_short macro to really be a max()
USB: serial: console: fix use-after-free after failed setup
USB: serial: qcserial: add Dell DW5818, DW5819
USB: serial: option: add support for TP-Link LTE module
USB: serial: cp210x: add support for ELV TFD500
USB: serial: ftdi_sio: add id for Cypress WICED dev board
bio_copy_user_iov(): don't ignore ->iov_offset
more bio_map_user_iov() leak fixes
fix unbalanced page refcounting in bio_map_user_iov
direct-io: Prevent NULL pointer access in submit_page_section
usb: gadget: composite: Fix use-after-free in usb_composite_overwrite_options
usb: gadget: configfs: Fix memory leak of interface directory data
drm/i915/bios: parse DDI ports also for CHV for HDMI DDC pin and DP AUX channel
drm/i915: Read timings from the correct transcoder in intel_crtc_mode_get()
drm/i915/edp: Get the Panel Power Off timestamp after panel is off
ALSA: line6: Fix leftover URB at error-path during probe
ALSA: line6: Fix missing initialization before error path
ALSA: caiaq: Fix stray URB at probe error path
ALSA: seq: Fix copy_from_user() call inside lock
ALSA: seq: Fix use-after-free at creating a port
ALSA: usb-audio: Kill stray URB at exiting
fs/mpage.c: fix mpage_writepage() for pages with buffers
device property: Track owner device of device property
iommu/amd: Finish TLB flush in amd_iommu_unmap()
pinctrl/amd: Fix build dependency on pinmux code
usb: renesas_usbhs: Fix DMAC sequence for receiving zero-length packet
KVM: nVMX: fix guest CR4 loading when emulating L2 to L1 exit
KVM: MMU: always terminate page walks at level 1
crypto: shash - Fix zero-length shash ahash digest crash
HID: usbhid: fix out-of-bounds bug
dmaengine: ti-dma-crossbar: Fix possible race condition with dma_inuse
dmaengine: edma: Align the memcpy acnt array size with the transfer
MIPS: math-emu: Remove pr_err() calls from fpu_emu()
USB: dummy-hcd: Fix deadlock caused by disconnect detection
rcu: Allow for page faults in NMI handlers
nl80211: Define policy for packet pattern attributes
CIFS: Reconnect expired SMB sessions
ext4: in ext4_seek_{hole,data}, return -ENXIO for negative offsets
Change-Id: I64affb40416c282aa1421e22e4320d5b99670af9
Signed-off-by: Kyle Yan <kyan@codeaurora.org>
commit 28585a832602747cbfa88ad8934013177a3aae38 upstream.
A number of architecture invoke rcu_irq_enter() on exception entry in
order to allow RCU read-side critical sections in the exception handler
when the exception is from an idle or nohz_full CPU. This works, at
least unless the exception happens in an NMI handler. In that case,
rcu_nmi_enter() would already have exited the extended quiescent state,
which would mean that rcu_irq_enter() would (incorrectly) cause RCU
to think that it is again in an extended quiescent state. This will
in turn result in lockdep splats in response to later RCU read-side
critical sections.
This commit therefore causes rcu_irq_enter() and rcu_irq_exit() to
take no action if there is an rcu_nmi_enter() in effect, thus avoiding
the unscheduled return to RCU quiescent state. This in turn should
make the kernel safe for on-demand RCU voyeurism.
Link: http://lkml.kernel.org/r/20170922211022.GA18084@linux.vnet.ibm.com
Fixes: 0be964be0 ("module: Sanitize RCU usage and locking")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Paul E. McKenneyauthored and Greg Kroah-Hartmancommited 2017-10-18 09:35:38 +02:00
* 4.9/tmp-9ae2c67:
Linux 4.9.40
alarmtimer: don't rate limit one-shot timers
tracing: Fix kmemleak in instance_rmdir
PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present
reiserfs: Don't clear SGID when inheriting ACLs
spmi: Include OF based modalias in device uevent
of: device: Export of_device_{get_modalias, uvent_modalias} to modules
acpi/nfit: Fix memory corruption/Unregister mce decoder on failure
ovl: fix random return value on mount
hfsplus: Don't clear SGID when inheriting ACLs
mlx5: Avoid that mlx5_ib_sg_to_klms() overflows the klms[] array
drm/mst: Avoid processing partially received up/down message transactions
drm/mst: Avoid dereferencing a NULL mstb in drm_dp_mst_handle_up_req()
drm/mst: Fix error handling during MST sideband message reception
RDMA/core: Initialize port_num in qp_attr
ceph: fix race in concurrent readdir
staging: lustre: ko2iblnd: check copy_from_iter/copy_to_iter return code
staging: sm750fb: avoid conflicting vesafb
staging: comedi: ni_mio_common: fix AO timer off-by-one regression
staging: rtl8188eu: add TL-WN722N v2 support
Revert "perf/core: Drop kernel samples even though :u is specified"
perf annotate: Fix broken arrow at row 0 connecting jmp instruction to its target
iser-target: Avoid isert_conn->cm_id dereference in isert_login_recv_done
target: Fix COMPARE_AND_WRITE caw_sem leak during se_cmd quiesce
udf: Fix deadlock between writeback and udf_setsize()
NFS: only invalidate dentrys that are clearly invalid.
sunrpc: use constant time memory comparison for mac
IB/core: Namespace is mandatory input for address resolution
IB/iser: Fix connection teardown race condition
Input: i8042 - fix crash at boot time
MIPS: Fix a typo: s/preset/present/ in r2-to-r6 emulation error message
MIPS: Send SIGILL for R6 branches in `__compute_return_epc_for_insn'
MIPS: Send SIGILL for linked branches in `__compute_return_epc_for_insn'
MIPS: Rename `sigill_r6' to `sigill_r2r6' in `__compute_return_epc_for_insn'
MIPS: Send SIGILL for BPOSGE32 in `__compute_return_epc_for_insn'
MIPS: math-emu: Prevent wrong ISA mode instruction emulation
MIPS: Fix unaligned PC interpretation in `compute_return_epc'
MIPS: Actually decode JALX in `__compute_return_epc_for_insn'
MIPS: Save static registers before sysmips
MIPS: Fix MIPS I ISA /proc/cpuinfo reporting
x86/ioapic: Pass the correct data to unmask_ioapic_irq()
x86/acpi: Prevent out of bound access caused by broken ACPI tables
Revert "ACPI / EC: Enable event freeze mode..." to fix a regression
ACPI / EC: Drop EC noirq hooks to fix a regression
ubifs: Don't leak kernel memory to the MTD
MIPS: Negate error syscall return in trace
MIPS: Fix mips_atomic_set() with EVA
MIPS: Fix mips_atomic_set() retry condition
ftrace: Fix uninitialized variable in match_records()
nvme-rdma: remove race conditions from IB signalling
vfio: New external user group/file match
vfio: Fix group release deadlock
ovl: drop CAP_SYS_RESOURCE from saved mounter's credentials
drm/ttm: Fix use-after-free in ttm_bo_clean_mm
f2fs: Don't clear SGID when inheriting ACLs
f2fs: sanity check size of nat and sit cache
xfs: Don't clear SGID when inheriting ACLs
ipmi:ssif: Add missing unlock in error branch
ipmi: use rcu lock around call to intf->handlers->sender()
drm/radeon: Fix eDP for single-display iMac10,1 (v2)
drm/radeon/ci: disable mclk switching for high refresh rates (v2)
drm/amd/amdgpu: Return error if initiating read out of range on vram
s390/syscalls: Fix out of bounds arguments access
Raid5 should update rdev->sectors after reshape
ext2: Don't clear SGID when inheriting ACLs
libnvdimm: fix badblock range handling of ARS range
libnvdimm, btt: fix btt_rw_page not returning errors
cx88: Fix regression in initial video standard setting
x86/xen: allow userspace access during hypercalls
md: don't use flush_signals in userspace processes
usb: renesas_usbhs: gadget: disable all eps when the driver stops
usb: renesas_usbhs: fix usbhsc_resume() for !USBHSF_RUNTIME_PWCTRL
USB: cdc-acm: add device-id for quirky printer
usb: storage: return on error to avoid a null pointer dereference
mxl111sf: Fix driver to use heap allocate buffers for USB messages
xhci: Bad Ethernet performance plugged in ASM1042A host
xhci: Fix NULL pointer dereference when cleaning up streams for removed host
xhci: fix 20000ms port resume timeout
ipvs: SNAT packet replies only for NATed connections
PCI/PM: Restore the status of PCI devices across hibernation
PCI: rockchip: Use normal register bank for config accessors
PCI: Work around poweroff & suspend-to-RAM issue on Macbook Pro 11
af_key: Fix sadb_x_ipsecrequest parsing
powerpc/mm/radix: Properly clear process table entry
powerpc/asm: Mark cr0 as clobbered in mftb()
powerpc: Fix emulation of mfocrf in emulate_step()
powerpc: Fix emulation of mcrf in emulate_step()
powerpc/64: Fix atomic64_inc_not_zero() to return an int
powerpc/pseries: Fix passing of pp0 in updatepp() and updateboltedpp()
xen/scsiback: Fix a TMR related use-after-free
iscsi-target: Add login_keys_workaround attribute for non RFC initiators
scsi: Add STARGET_CREATED_REMOVE state to scsi_target_state
scsi: ses: do not add a device to an enclosure if enclosure_add_links() fails.
PM / Domains: Fix unsafe iteration over modified list of domains
PM / Domains: Fix unsafe iteration over modified list of domain providers
PM / Domains: Fix unsafe iteration over modified list of device links
ASoC: compress: Derive substream from stream based on direction
igb: Explicitly select page 0 at initialization
btrfs: Don't clear SGID when inheriting ACLs
wlcore: fix 64K page support
Bluetooth: use constant time memory comparison for secret values
perf intel-pt: Clear FUP flag on error
perf intel-pt: Use FUP always when scanning for an IP
perf intel-pt: Ensure never to set 'last_ip' when packet 'count' is zero
perf intel-pt: Fix last_ip usage
perf intel-pt: Ensure IP is zero when state is INTEL_PT_STATE_NO_IP
perf intel-pt: Fix missing stack clear
perf intel-pt: Improve sample timestamp
perf intel-pt: Move decoder error setting into one condition
NFC: Add sockaddr length checks before accessing sa_family in bind handlers
nfc: Fix the sockaddr length sanitization in llcp_sock_connect
nfc: Ensure presence of required attributes in the activate_target handler
NFC: nfcmrvl: fix firmware-management initialisation
NFC: nfcmrvl: use nfc-device for firmware download
NFC: nfcmrvl: do not use device-managed resources
NFC: nfcmrvl_uart: add missing tty-device sanity check
NFC: fix broken device allocation
ath9k: fix an invalid pointer dereference in ath9k_rng_stop()
ath9k: fix tx99 bus error
ath9k: fix tx99 use after free
thermal: cpu_cooling: Avoid accessing potentially freed structures
thermal: max77620: fix device-node reference imbalance
s5p-jpeg: don't return a random width/height
dm mpath: cleanup -Wbool-operation warning in choose_pgpath()
ir-core: fix gcc-7 warning on bool arithmetic
disable new gcc-7.1.1 warnings for now
Use %zu to print resid (size_t).
ANDROID: keychord: Fix a slab out-of-bounds read.
UPSTREAM: af_key: Fix sadb_x_ipsecrequest parsing
ANDROID: lowmemorykiller: Add tgid to kill message
Revert "ANDROID: proc: smaps: Allow smaps access for CAP_SYS_RESOURCE"
4.9.39
kvm: vmx: allow host to access guest MSR_IA32_BNDCFGS
kvm: vmx: Check value written to IA32_BNDCFGS
kvm: x86: Guest BNDCFGS requires guest MPX support
kvm: vmx: Do not disable intercepts for BNDCFGS
tracing: Use SOFTIRQ_OFFSET for softirq dectection for more accurate results
PM / QoS: return -EINVAL for bogus strings
PM / wakeirq: Convert to SRCU
sched/topology: Fix overlapping sched_group_mask
sched/topology: Optimize build_group_mask()
sched/topology: Fix building of overlapping sched-groups
sched/fair, cpumask: Export for_each_cpu_wrap()
Revert "sched/core: Optimize SCHED_SMT"
crypto: caam - fix signals handling
crypto: caam - properly set IV after {en,de}crypt
crypto: sha1-ssse3 - Disable avx2
crypto: atmel - only treat EBUSY as transient if backlog
crypto: talitos - Extend max key length for SHA384/512-HMAC and AEAD
mm: fix overflow check in expand_upwards()
selftests/capabilities: Fix the test_execve test
mnt: Make propagate_umount less slow for overlapping mount propagation trees
mnt: In propgate_umount handle visiting mounts in any order
mnt: In umount propagation reparent in a separate pass
nvmem: core: fix leaks on registration errors
rcu: Add memory barriers for NOCB leader wakeup
vt: fix unchecked __put_user() in tioclinux ioctls
ARM64: dts: marvell: armada37xx: Fix timer interrupt specifiers
exec: Limit arg stack to at most 75% of _STK_LIM
s390: reduce ELF_ET_DYN_BASE
powerpc: move ELF_ET_DYN_BASE to 4GB / 4MB
arm64: move ELF_ET_DYN_BASE to 4GB / 4MB
arm: move ELF_ET_DYN_BASE to 4MB
binfmt_elf: use ELF_ET_DYN_BASE only for PIE
checkpatch: silence perl 5.26.0 unescaped left brace warnings
fs/dcache.c: fix spin lockup issue on nlru->lock
mm/list_lru.c: fix list_lru_count_node() to be race free
kernel/extable.c: mark core_kernel_text notrace
thp, mm: fix crash due race in MADV_FREE handling
tools/lib/lockdep: Reduce MAX_LOCK_DEPTH to avoid overflowing lock_chain/: Depth
parisc/mm: Ensure IRQs are off in switch_mm()
parisc: DMA API: return error instead of BUG_ON for dma ops on non dma devs
parisc: use compat_sys_keyctl()
parisc: Report SIGSEGV instead of SIGBUS when running out of stack
irqchip/gic-v3: Fix out-of-bound access in gic_set_affinity
cfg80211: Check if NAN service ID is of expected size
cfg80211: Check if PMKID attribute is of expected size
cfg80211: Validate frequencies nested in NL80211_ATTR_SCAN_FREQUENCIES
cfg80211: Define nla_policy for NL80211_ATTR_LOCAL_MESH_POWER_MODE
sfc: don't read beyond unicast address list
brcmfmac: Fix glom_skb leak in brcmf_sdiod_recv_chain
brcmfmac: Fix a memory leak in error handling path in 'brcmf_cfg80211_attach'
brcmfmac: fix possible buffer overflow in brcmf_cfg80211_mgmt_tx()
rds: tcp: use sock_create_lite() to create the accept socket
vrf: fix bug_on triggered by rx when destroying a vrf
net: ipv6: Compare lwstate in detecting duplicate nexthops
net: core: Fix slab-out-of-bounds in netdev_stats_to_stats64
vxlan: fix hlist corruption
ipv6: dad: don't remove dynamic addresses if link is down
net/mlx5e: Fix TX carrier errors report in get stats ndo
liquidio: fix bug in soft reset failure detection
net/mlx5: Cancel delayed recovery work when unloading the driver
net: handle NAPI_GRO_FREE_STOLEN_HEAD case also in napi_frags_finish()
bpf: prevent leaking pointer via xadd on unpriviledged
rocker: move dereference before free
bridge: mdb: fix leak on complete_info ptr on fail path
net: prevent sign extension in dev_get_stats()
tcp: reset sk_rx_dst in tcp_disconnect()
net: dp83640: Avoid NULL pointer dereference.
ipv6: avoid unregistering inet6_dev for loopback
net/phy: micrel: configure intterupts after autoneg workaround
net: sched: Fix one possible panic when no destroy callback
net_sched: fix error recovery at qdisc creation
xen-netfront: Rework the fix for Rx stall during OOM and network stress
ANDROID: android-verity: mark dev as rw for linear target
ANDROID: sdcardfs: Remove unnecessary lock
ANDROID: binder: don't check prio permissions on restore.
Add BINDER_GET_NODE_DEBUG_INFO ioctl
ANDROID: binder: add RT inheritance flag to node.
ANDROID: binder: improve priority inheritance.
ANDROID: binder: add min sched_policy to node.
ANDROID: binder: add support for RT prio inheritance.
ANDROID: binder: push new transactions to waiting threads.
ANDROID: binder: remove proc waitqueue
Conflicts:
drivers/staging/android/lowmemorykiller.c
Change-Id: I2954e47d7e4fc74cf9bb5033fc151537958b78af
Signed-off-by: Kyle Yan <kyan@codeaurora.org>
commit 6b5fc3a1331810db407c9e0e673dc1837afdc9d0 upstream.
Wait/wakeup operations do not guarantee ordering on their own. Instead,
either locking or memory barriers are required. This commit therefore
adds memory barriers to wake_nocb_leader() and nocb_leader_wait().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Krister Johansen <kjlx@templeofstupid.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Paul E. McKenneyauthored and Greg Kroah-Hartmancommited 2017-07-21 07:42:22 +02:00
RCU_EXPEDITE_BOOT should speed up the boot process by enforcing
synchronize_rcu_expedited() instead of synchronize_rcu() during the boot
process. There should be no reason why one does not want this and there
is no need worry about real time latency at this point.
Therefore make it default.
Note that users wishing to avoid expediting entirely, for example when
bringing up new hardware possibly having flaky IPIs, can use the
rcu_normal boot parameter to override boot-time expediting.
Change-Id: I758bb7819bb2b18ad7232c3e943b9c1cb85d49e9
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
[ paulmck: Reworded commit log. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Sebastian Andrzej Siewiorauthored and Kyle Yancommited 2017-05-05 15:41:33 -07:00
Neeraj Upadhyay
authored and
Sorayukii
commited 
Joel Fernandes (Google)
authored and
Paul E. McKenney
authored and
Steven Rostedt (VMware)
authored and
Yaroslav Furman
authored and
Paul E. McKenney
authored and
Paul E. McKenney
authored and
Peter Zijlstra (Intel)
authored and
Yousef Algadri
authored and
jianzhou
commited 
Greg Kroah-Hartman
commited 
Zhang, Jun
authored and
Blagovest Kolenichev
commited 
Tejun Heo
authored and
Kyle Yan
commited 
Sebastian Andrzej Siewior
authored and