Commit Graph

810809 Commits

Author SHA1 Message Date
Paul E. McKenney 3a6cb58f15 rcutorture: Add grace period after CPU offline
Beyond a certain point in the CPU-hotplug offline process, timers get
stranded on the outgoing CPU, and won't fire until that CPU comes back
online, which might well be never.  This commit therefore adds a hook
in torture_onoff_init() that is invoked from torture_offline(), which
rcutorture uses to occasionally wait for a grace period.  This should
result in failures for RCU implementations that rely on stranded timers
eventually firing in the absence of the CPU coming back online.

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:37:10 -08:00
Paul E. McKenney 0d8a9ea976 torture: Explain and simplify odd "for" loop in mkinitrd.sh
Why a Bourne-shell "for" loop?  And why 192 instances of "a"?  This commit
adds a shell comment to present the answer to these mysteries.  It also
uses a series of factor-of-four Bourne-shell assignments to make it
easy to see how many instances there are, replacing the earlier wall of
'a' characters.

Reported-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
[ paulmck: Fix wrong-variable bugs noted by Andrea Parri. ]
2019-01-25 15:37:09 -08:00
Paul E. McKenney cd618d102b rcutorture: Record grace periods in forward-progress histogram
This commit records grace periods in rcutorture's n_launders_hist[]
histogram, thus allowing rcu_torture_fwd_cb_hist() to print out the
elapsed number of grace periods between buckets.  This information
helps to determine whether a lack of forward progress is due to stalled
grace periods on the one hand or due to sluggish callback invocation on
the other.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:37:09 -08:00
Paul E. McKenney 7a968bb26a Merge branches 'consolidate.2019.01.26a' and 'fwd.2019.01.26a' into HEAD
consolidate.2019.01.26a: RCU flavor consolidation cleanups.
fwd.2019.01.26a: RCU grace-period forward-progress fixes.
2019-01-25 15:32:01 -08:00
Zhang, Jun 13dc7d0c7a rcu: Prevent needless ->gp_seq_needed update in __note_gp_changes()
Currently, __note_gp_changes() checks to see if the rcu_node structure's
->gp_seq_needed is greater than or equal to that of the rcu_data
structure, and if so, updates the rcu_data structure's ->gp_seq_needed
field.  This results in a useless store in the case where the two fields
are equal.

This commit therefore carries out this store only in the case where the
rcu_node structure's ->gp_seq_needed is strictly greater than that of
the rcu_data structure.

Signed-off-by: "Zhang, Jun" <jun.zhang@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Link: https://lkml.kernel.org/r/88DC34334CA3444C85D647DBFA962C2735AD5F77@SHSMSX104.ccr.corp.intel.com
2019-01-25 15:30:00 -08:00
Zhang, Jun 1d1f898df6 rcu: Do RCU GP kthread self-wakeup from softirq and interrupt
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
2019-01-25 15:29:59 -08:00
Paul E. McKenney 2ccaff10f7 rcu: Add sysrq rcu_node-dump capability
Life is hard if RCU manages to get stuck without triggering RCU CPU
stall warnings or triggering the rcu_check_gp_start_stall() checks
for failing to start a grace period.  This commit therefore adds a
boot-time-selectable sysrq key (commandeering "y") that allows manually
dumping Tree RCU state.  The new rcutree.sysrq_rcu kernel boot parameter
must be set for this sysrq to be available.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:59 -08:00
Paul E. McKenney 3b6505fd8e rcu: Protect rcu_check_gp_kthread_starvation() access to ->gp_flags
The rcu_check_gp_kthread_starvation() function can be invoked without
holding locks, so the access to the rcu_state structure's ->gp_flags
field must be protected with READ_ONCE().  This commit therefore adds
this protection.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:58 -08:00
Paul E. McKenney fd897573fa rcu: Improve diagnostics for failed RCU grace-period start
If a grace period fails to start (for example, because you commented
out the last two lines of rcu_accelerate_cbs_unlocked()), rcu_core()
will invoke rcu_check_gp_start_stall(), which will notice and complain.
However, this complaint is lacking crucial debugging information such
as when the last wakeup executed and what the value of ->gp_seq was at
that time.  This commit therefore removes the current pr_alert() from
rcu_check_gp_start_stall(), instead invoking show_rcu_gp_kthreads(),
which has been updated to print the needed information, which is collected
by rcu_gp_kthread_wake().

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:57 -08:00
Paul E. McKenney a9fefdb257 rcu: Update NOCB comments
This commit updates a few obsolete comments in the RCU callback-offload
code.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:57 -08:00
Paul E. McKenney b2c1955b88 rcu: Remove unused rcu_cpu_kthread_cpu per-CPU variable
The rcu_cpu_kthread_cpu used to provide debugfs information, but is no
longer used.  This commit therefore removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:56 -08:00
Paul E. McKenney f7e972ee12 rcu: Move rcu_cpu_has_work to rcu_data structure
Given that RCU has a perfectly good per-CPU rcu_data structure, most
per-CPU quantities should be stored there.

This commit therefore moves the rcu_cpu_has_work per-CPU variable to
the rcu_data structure.  This also makes this variable unconditionally
present, which should be acceptable given the memory reduction due to the
RCU flavor consolidation and also due to simplifications this will enable.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:56 -08:00
Paul E. McKenney 8b4d0f4858 rcu: Remove unused rcu_cpu_kthread_loops per-CPU variable
The rcu_cpu_kthread_loops variable used to provide debugfs information,
but is no longer used.  This commit therefore removes it.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:55 -08:00
Paul E. McKenney 6ffdde28b7 rcu: Move rcu_cpu_kthread_status to rcu_data structure
Given that RCU has a perfectly good per-CPU rcu_data structure, most
per-CPU quantities should be stored there.

This commit therefore moves the rcu_cpu_kthread_status per-CPU variable
to the rcu_data structure.  This also makes this variable unconditionally
present, which should be acceptable given the memory reduction due to the
RCU flavor consolidation and also due to simplifications this will enable.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:54 -08:00
Paul E. McKenney 37f62d7cf0 rcu: Move rcu_cpu_kthread_task to rcu_data structure
Given that RCU has a perfectly good per-CPU rcu_data structure, most
per-CPU quantities should be stored there.

This commit therefore moves the rcu_cpu_kthread_task per-CPU variable to
the rcu_data structure.  This also makes this variable unconditionally
present, which should be acceptable given the memory reduction due to the
RCU flavor consolidation and also due to simplifications this will enable.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:53 -08:00
Paul E. McKenney 9cf422a8e7 rcu: Accommodate zero jiffies_till_first_fqs and kthread kicking
It is perfectly fine to set the rcutree.jiffies_till_first_fqs boot
parameter to zero, in fact, this can be useful on specialty systems that
usually have at least one idle CPU and that need fast grace periods.
This is because this setting causes the RCU grace-period kthread to
scan for idle threads immediately after grace-period initialization,
as opposed to waiting several jiffies to do so.

It is also perfectly fine to set the rcutree.rcu_kick_kthreads kernel
parameter, which gives the RCU grace-period kthread an extra wakeup
if it doesn't make progress for a period of three times the setting of
the rcutree.jiffies_till_first_fqs boot parameter.  This is of course
problematic when the value of this parameter is zero, as it can result
in unnecessary wakeup IPIs along with unnecessary WARN_ONCE() invocations.

This commit therefore defers kthread kicking for at least two jiffies,
regardless of the setting of rcutree.jiffies_till_first_fqs.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:29:53 -08:00
Paul E. McKenney 6ba7d681ac rcu: Remove wrapper definitions for obsolete RCU update functions
None of synchronize_rcu_bh, synchronize_rcu_bh_expedited, call_rcu_bh,
rcu_barrier_bh, synchronize_sched, synchronize_sched_expedited,
call_rcu_sched, rcu_barrier_sched, get_state_synchronize_sched, and
cond_synchronize_sched are actually used.  This commit therefore removes
their trivial wrapper-function definitions.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:31 -08:00
Paul E. McKenney 260e1e4fd8 rcu: Discard separate per-CPU callback counts
Back when there were multiple flavors of RCU, it was necessary to
separately count lazy and non-lazy callbacks for each CPU.  These counts
were used in CONFIG_RCU_FAST_NO_HZ kernels to determine how long a newly
idle CPU should be allowed to sleep before handling its RCU callbacks.
But now that there is only one flavor, the callback counts for a given
CPU's sole rcu_data structure are the counts for that CPU.

This commit therefore removes the rcu_data structure's ->nonlazy_posted
and ->nonlazy_posted_snap fields, the rcu_idle_count_callbacks_posted()
and rcu_cpu_has_callbacks() functions, repurposes the rcu_data structure's
->all_lazy field to record the laziness state at the beginning of the
latest idle sojourn, and modifies CONFIG_RCU_FAST_NO_HZ RCU CPU stall
warnings accordingly.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:30 -08:00
Paul E. McKenney 8923072664 rcu: Inline _synchronize_rcu_expedited() into synchronize_rcu_expedited()
Now that _synchronize_rcu_expedited() has only one caller, and given that
this is a tail call, this commit inlines _synchronize_rcu_expedited()
into synchronize_rcu_expedited().

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:29 -08:00
Paul E. McKenney e5bc3af773 rcu: Consolidate PREEMPT and !PREEMPT synchronize_rcu()
Now that rcu_blocking_is_gp() makes the correct immediate-return
decision for both PREEMPT and !PREEMPT, a single implementation of
synchronize_rcu() will work correctly under both configurations.
This commit therefore eliminates a few lines of code by consolidating
the two implementations of synchronize_rcu().

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:28 -08:00
Paul E. McKenney 3cd4ca47aa rcu: Consolidate PREEMPT and !PREEMPT synchronize_rcu_expedited()
The CONFIG_PREEMPT=n and CONFIG_PREEMPT=y implementations of
synchronize_rcu_expedited() are quite similar, and with small
modifications to rcu_blocking_is_gp() can be made identical.  This commit
therefore makes this change in order to save a few lines of code and to
reduce the amount of duplicate code.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:27 -08:00
Paul E. McKenney 142d106d5e rcu: Determine expedited-GP IPI handler at build time
Back when there could be multiple RCU flavors running in the same kernel
at the same time, it was necessary to specify the expedited grace-period
IPI handler at runtime.  Now that there is only one RCU flavor, the
IPI handler can be determined at build time.  There is therefore no
longer any reason for the RCU-preempt and RCU-sched IPI handlers to
have different names, nor is there any reason to pass these handlers in
function arguments and in the data structures enclosing workqueues.

This commit therefore makes all these changes, pushing the specification
of the expedited grace-period IPI handler down to the point of use.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:27 -08:00
Paul E. McKenney c46f497a61 rcu: Inline rcu_kthread_do_work() into its sole remaining caller
The rcu_kthread_do_work() function has a single-line body and only one
remaining caller.  This commit therefore saves a few lines of code by
inlining rcu_kthread_do_work() into its sole remaining caller.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:25 -08:00
Paul E. McKenney c97058d033 rcu: Eliminate RCU_BH_FLAVOR and RCU_SCHED_FLAVOR
Now that the RCU flavors have been consolidated, RCU_BH_FLAVOR and
RCU_SCHED_FLAVOR are no longer used.  This commit therefore saves a
few lines by removing them.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:25 -08:00
Paul E. McKenney cd920e5a34 rcu: Inline force_quiescent_state() into rcu_force_quiescent_state()
Given that rcu_force_quiescent_state() is a simple wrapper around
force_quiescent_state(), this commit saves a few lines of code by
inlining force_quiescent_state() into rcu_force_quiescent_state(),
and changing all references to force_quiescent_state() to instead
invoke rcu_force_quiescent_state().

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:24 -08:00
Paul E. McKenney 1de462ed85 rcu: Make expedited IPI handler return after handling critical section
During expedited RCU grace-period initialization, IPIs are sent to
all non-idle online CPUs.  The IPI handler checks to see if the CPU is
in quiescent state, reporting one if so.  This handler looks at three
different cases: (1) The CPU is not in an rcu_read_lock()-based critical
section, (2) The CPU is in the process of exiting an rcu_read_lock()-based
critical section, and (3) The CPU is in an rcu_read_lock()-based critical
section.  In case (2), execution falls through into case (3).

This is harmless from a functionality viewpoint, but can result in
needless overhead during an improbable corner case.  This commit therefore
adds the "return" statement needed to prevent fall-through.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:24 -08:00
Paul E. McKenney ad368d15b0 rcu: Rename and comment changes due to only one rcuo kthread per CPU
Given RCU flavor consolidation, the name rcu_spawn_all_nocb_kthreads()
is quite misleading.  It no longer ever creates more than one kthread,
and it does so only for the specified CPU.  This commit therefore changes
this name to the more descriptive rcu_spawn_cpu_nocb_kthread(), and also
fixes up a similar issue in its header comment while in the area.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
2019-01-25 15:28:23 -08:00
Paul E. McKenney b290ebcf7b sched: Replace synchronize_sched() with synchronize_rcu()
Now that synchronize_rcu() waits for preempt-disable regions of
code as well as RCU read-side critical sections, synchronize_sched()
can be replaced by synchronize_rcu(), in fact, synchronize_sched()
is now completely equivalent to synchronize_rcu().  This commit
therefore replaces synchronize_sched() with synchronize_rcu() so that
synchronize_sched() can eventually be removed entirely.

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2019-01-25 15:28:22 -08:00
Paul E. McKenney 337e9b07db sched: Replace call_rcu_sched() with call_rcu()
Now that call_rcu()'s callback is not invoked until after all
preempt-disable regions of code have completed (in addition to explicitly
marked RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_sched().  This commit therefore makes that change.

While in the area, this commit also updates an outdated header comment
for for_each_domain().

Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
2019-01-25 15:28:22 -08:00
Paul E. McKenney 910cc9591d tools/memory-model: Make scripts take "-j" abbreviation for "--jobs"
The "--jobs" argument to the litmus-test scripts is similar to the "-jN"
argument to "make", so this commit allows the "-jN" form as well.  While
in the area, it also prohibits the various forms of "-j0".

Suggested-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20181203230451.28921-3-paulmck@linux.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:07:04 +01:00
Paul E. McKenney b02eb5b096 tools/memory-model: Add scripts to check github litmus tests
The https://github.com/paulmckrcu/litmus repository contains a large
number of C-language litmus tests that include "Result:" comments
predicting the verification result.  This commit adds a number of scripts
that run tests on these litmus tests:

checkghlitmus.sh:
	Runs all litmus tests in the https://github.com/paulmckrcu/litmus
        archive that are C-language and that have "Result:" comment lines
	documenting expected results, comparing the actual results to
	those expected.  Clones the repository if it has not already
	been cloned into the "tools/memory-model/litmus" directory.

initlitmushist.sh
	Run all litmus tests having no more than the specified number
	of processes given a specified timeout, recording the results in
	.litmus.out files.  Clones the repository if it has not already
	been cloned into the "tools/memory-model/litmus" directory.

newlitmushist.sh
	For all new or updated litmus tests having no more than the
	specified number of processes given a specified timeout, run
	and record the results in .litmus.out files.

checklitmushist.sh
	Run all litmus tests having .litmus.out files from previous
	initlitmushist.sh or newlitmushist.sh runs, comparing the
	herd output to that of the original runs.

The above scripts will run litmus tests concurrently, by default with
one job per available CPU.  Giving any of these scripts the --help
argument will cause them to print usage information.

This commit also adds a number of helper scripts that are not intended
to be invoked from the command line:

cmplitmushist.sh: Compare the output of two different runs of the same
	litmus test.

judgelitmus.sh: Compare the output of a litmus test to its "Result:"
	comment line.

parseargs.sh: Parse command-line arguments.

runlitmushist.sh: Run the litmus tests whose pathnames are provided one
	per line on standard input.

While in the area, this commit also makes the existing checklitmus.sh
and checkalllitmus.sh scripts use parseargs.sh in order to provide a
bit of uniformity.  In addition, per-litmus-test status output is directed
to stdout, while end-of-test summary information is directed to stderr.
Finally, the error flag standardizes on "!!!" to assist those familiar
with rcutorture output.

The defaults for the parseargs.sh arguments may be overridden by using
environment variables: LKMM_DESTDIR for --destdir, LKMM_HERD_OPTIONS
for --herdoptions, LKMM_JOBS for --jobs, LKMM_PROCS for --procs, and
LKMM_TIMEOUT for --timeout.

[ paulmck: History-check summary-line changes per Alan Stern feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akiyks@gmail.com
Cc: boqun.feng@gmail.com
Cc: dhowells@redhat.com
Cc: j.alglave@ucl.ac.uk
Cc: linux-arch@vger.kernel.org
Cc: luc.maranget@inria.fr
Cc: npiggin@gmail.com
Cc: parri.andrea@gmail.com
Cc: stern@rowland.harvard.edu
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/20181203230451.28921-2-paulmck@linux.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:06:59 +01:00
Andrea Parri 5b735eb1ce tools/memory-model: Model smp_mb__after_unlock_lock()
The kernel documents smp_mb__after_unlock_lock() the following way:

  "Place this after a lock-acquisition primitive to guarantee that
   an UNLOCK+LOCK pair acts as a full barrier.  This guarantee applies
   if the UNLOCK and LOCK are executed by the same CPU or if the
   UNLOCK and LOCK operate on the same lock variable."

Formalize in LKMM the above guarantee by defining (new) mb-links according
to the law:

  ([M] ; po ; [UL] ; (co | po) ; [LKW] ;
	fencerel(After-unlock-lock) ; [M])

where the component ([UL] ; co ; [LKW]) identifies "UNLOCK+LOCK pairs on
the same lock variable" and the component ([UL] ; po ; [LKW]) identifies
"UNLOCK+LOCK pairs executed by the same CPU".

In particular, the LKMM forbids the following two behaviors (the second
litmus test below is based on:

  Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html

c.f., Section "Tree RCU Grace Period Memory Ordering Building Blocks"):

C after-unlock-lock-same-cpu

(*
 * Result: Never
 *)

{}

P0(spinlock_t *s, spinlock_t *t, int *x, int *y)
{
	int r0;

	spin_lock(s);
	WRITE_ONCE(*x, 1);
	spin_unlock(s);
	spin_lock(t);
	smp_mb__after_unlock_lock();
	r0 = READ_ONCE(*y);
	spin_unlock(t);
}

P1(int *x, int *y)
{
	int r0;

	WRITE_ONCE(*y, 1);
	smp_mb();
	r0 = READ_ONCE(*x);
}

exists (0:r0=0 /\ 1:r0=0)

C after-unlock-lock-same-lock-variable

(*
 * Result: Never
 *)

{}

P0(spinlock_t *s, int *x, int *y)
{
	int r0;

	spin_lock(s);
	WRITE_ONCE(*x, 1);
	r0 = READ_ONCE(*y);
	spin_unlock(s);
}

P1(spinlock_t *s, int *y, int *z)
{
	int r0;

	spin_lock(s);
	smp_mb__after_unlock_lock();
	WRITE_ONCE(*y, 1);
	r0 = READ_ONCE(*z);
	spin_unlock(s);
}

P2(int *z, int *x)
{
	int r0;

	WRITE_ONCE(*z, 1);
	smp_mb();
	r0 = READ_ONCE(*x);
}

exists (0:r0=0 /\ 1:r0=0 /\ 2:r0=0)

Signed-off-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Akira Yokosawa <akiyks@gmail.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Daniel Lustig <dlustig@nvidia.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Jade Alglave <j.alglave@ucl.ac.uk>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Luc Maranget <luc.maranget@inria.fr>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arch@vger.kernel.org
Cc: parri.andrea@gmail.com
Link: http://lkml.kernel.org/r/20181203230451.28921-1-paulmck@linux.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-01-21 11:06:55 +01:00
Linus Torvalds d7393226d1 First 5.0 rc pull request
Not much so far, but I'm feeling like the 2nd PR -rc will be larger than
 this. We have the usual batch of bugs and two fixes to code merged this cycle.
 
 - Restore valgrind support for the ioctl verbs interface merged this window,
   and fix a missed error code on an error path from that conversion
 
 - A user reported crash on obsolete mthca hardware
 
 - pvrdma was using the wrong command opcode toward the hypervisor
 
 - NULL pointer crash regression when dumping rdma-cm over netlink
 
 - Be conservative about exposing the global rkey
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEfB7FMLh+8QxL+6i3OG33FX4gmxoFAlxBTeMACgkQOG33FX4g
 mxrOIQ//YdZdU9J825DM4ppH/MWRoPgayI+cca5sW2EG/nkgsvFJoiVDDK5/ka1g
 ge5Q21ZLMSPCBR0Iu/e/JOq6fJI4fsbcJGZURbyKgRZqyCBCf6qJbhiZKifpQMVb
 w7RP8kRFRdaiQzkAYfZSv9TP93JLvTDLg6zZ74r4vc8YphIzkI410v568hs6FiVu
 MIcb53pBWUswpCAnBVB+54sw+phJyjd02kmY4xTlWmiEzwHBb0JQ+Kps72/G0IWy
 0vOlDI1UjwqoDfThzyT7mcXqnSbXxg/e8EecMpyFzlorQyxgZ5TsJgQ8ubSYxuiQ
 7+dZ4rsdoZD++3MGtpmqDMQzKSPb989WzJT8WLp5oSw4ryAXeJJ+tys/APLtvPkf
 EgKgVyEqfxMDXn02/ENwDPpZyKLZkhcHFLgvfYmxtlDvtai/rvTLmzV1mptEaxlF
 +2pwSQM4/E/8qrLglN9kdFSfjBMb7Bvd2NYQqZ9vah2omb7gPsaTEEpVw6l/E0NX
 oOxFKPEzb0nP9KmJmwO8KLCvcrruuRL8kpmhc6sQMQJ6z0h4hmZrHF5EZZH92g0p
 maHyrx66vqw/Yl+TLvAb/T6FV1ax5c1TauiNErAjnag2wgVWW42Q7lQzSFLFI8su
 GU8oRlbIclDQ/1bszsf0IShq0r9G17+2n6yyTX39rj62YioiDlI=
 =ymZq
 -----END PGP SIGNATURE-----

Merge tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma

Pull rdma fixes frfom Jason Gunthorpe:
 "Not much so far. We have the usual batch of bugs and two fixes to code
  merged this cycle:

   - Restore valgrind support for the ioctl verbs interface merged this
     window, and fix a missed error code on an error path from that
     conversion

   - A user reported crash on obsolete mthca hardware

   - pvrdma was using the wrong command opcode toward the hypervisor

   - NULL pointer crash regression when dumping rdma-cm over netlink

   - Be conservative about exposing the global rkey"

* tag 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
  RDMA/uverbs: Mark ioctl responses with UVERBS_ATTR_F_VALID_OUTPUT
  RDMA/mthca: Clear QP objects during their allocation
  RDMA/vmw_pvrdma: Return the correct opcode when creating WR
  RDMA/cma: Add cm_id restrack resource based on kernel or user cm_id type
  RDMA/nldev: Don't expose unsafe global rkey to regular user
  RDMA/uverbs: Fix post send success return value in case of error
2019-01-18 17:17:20 +12:00
Linus Torvalds 1092a94fcb drm amdgpu, i915 gvt, sun4i, meson, rockchip, qxl, virtio fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIcBAABAgAGBQJcQRsZAAoJEAx081l5xIa+oKMP/A6jc+SmQgss3TD3WsrIMNUJ
 QoeKh5KQZqPDsz4sSQ27J6UIDKWuX9ZkzhOOgpKLECKK8CK5xpf14cKKwacyfW05
 8E9gB1kq4SRRNQxUvgrh6g3o3DHSanGtZUywMFN56MGfSxPMWytfzmQNDZ5XvAE5
 OrpRW+Nizs8uSrgvfoZoKOVuCaNVkZFxOTYXWwIPSJxmSuxGoX0nTnTdl0lNCSdE
 gSK82TIAxibfkeJ0K1MXCLbYTWXIvuoZY/JCWJ6wDAd21eK8IszsmVmn7Ou6q/sY
 aFNbKlaPuzdVe9MMRScAQLOBaoZSbiaIVA9UXXK/XR12K3Sqb6XU+NiRtrMWE5XF
 7Z8fkPCrfDG8oelcZW1iRRuZyL82I91xh7j+B20X+GMdHs+A+fT2YKLxbJBk1BMT
 3S/FdGfAnMqezgXDpqeoeYXoEsCaYtIls442FVcXSvQdOt7BjGlzXr+FBLFmvums
 4JL0yvcSTgo85N/hcM3FWLlBYVD6D65+fM42wPqyl05FgUTHF+Ev9503EjxsxQF6
 yCU4bsixnhxE21/v/Tw5Vhe3DU+zZqBWNpSocaWCfj7cyl1rDirZPbr/Tr6yuWgx
 mTR/B4tNGFiXsiPdQwmIGRSKWOWz+wDT7B9apKdIyn++hyFz6Rh/IScZFzqso5w8
 dq522vKrWbP5Jl/sA5GX
 =hgg/
 -----END PGP SIGNATURE-----

Merge tag 'drm-fixes-2019-01-18' of git://anongit.freedesktop.org/drm/drm

Pull drm fixes from Dave Airlie:
 "The rc3 fixes are a bit scattered:

   - meson, sun4i and rockchip all had missing of_node_put.

   - qxl and virtio both were advertising dma-buf to userspace when they
     really shouldn't have.

  Otherwise:

  meson:
   - modesetting regression fix

  i915 GVT:
   - one cmd parser failure fix
   - region cleanup fix in vGPU destroy

  amdgpu:
   - KFD fixes for arm64 mixed APU/DGPU
   - vega12 powerplay fix
   - raven DC fixes
   - freesync fix"

* tag 'drm-fixes-2019-01-18' of git://anongit.freedesktop.org/drm/drm:
  drm/amd/display: Detach backlight from stream
  drm/sun4i: backend: add missing of_node_puts
  Revert "drm/amdgpu: validate user pitch alignment"
  Revert "drm/amdgpu: validate user GEM object size"
  drm/meson: Fix atomic mode switching regression
  drm/i915/gvt: Fix mmap range check
  drm/i915/gvt: free VFIO region space in vgpu detach
  drm/amd/display: Fix disabled cursor on top screen edge
  drm/amd/display: fix warning on raven hotplug
  drm/amd/display: fix PME notification not working in RV desktop
  drm/amd/display: Only get the connector state for VRR when toggled
  drm/amd/display: Pack DMCU iRAM alignment
  drm/amd/powerplay: run acg btc for Vega12
  drm/amdkfd: Don't assign dGPUs to APU topology devices
  drm/amdkfd: Allow building KFD on ARM64 (v2)
  drm/meson: add missing of_node_put
  drm/virtio: drop prime import/export callbacks
  drm/qxl: drop prime import/export callbacks
  drm/i915/gvt: Allow F_CMD_ACCESS on mmio 0x21f0
  drm/rockchip: add missing of_node_put
2019-01-18 17:14:02 +12:00
Linus Torvalds 2451f3717c LED fix for 5.0-rc3
-----BEGIN PGP SIGNATURE-----
 
 iHUEABYIAB0WIQQUwxxKyE5l/npt8ARiEGxRG/Sl2wUCXED1agAKCRBiEGxRG/Sl
 2125AP4+hSXiVYvxgQg4zeAHzd00GKAIcYTudrzZ/iX5E19UlQD7B3h7HiTgvNIo
 QOvU+0PChsk/qwg1+Ztw8Gw3WZxl/wM=
 =I9ym
 -----END PGP SIGNATURE-----

Merge tag 'led-fix-for-5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds

Pull LED fix from Jacek Anaszewski.

* tag 'led-fix-for-5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski/linux-leds:
  leds: lp5523: fix a missing check of return value of lp55xx_read
2019-01-18 16:58:07 +12:00
Linus Torvalds 0a2fbed84a hwmon fixes for v5.0-rc3
Minor fixes/regressions.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJcQOvDAAoJEMsfJm/On5mBKZgP/22R1XvbJtr7UYCukAe4auoq
 qnwFClb4CXn2sw0z7nLid4lOHEaw9QRu6QycDH8oUCb4osO/TzHAuRhROfiie7cV
 0l54IdTsQ206qw+zKuYExg0l5rRrdqlGgyRvW22R/hhseMFG7BDMIfL+osT3RY+r
 q/rJyRl2S+XojEvi58zPgEr0bVpxudkvmppXNJl5fdPVeo1lschcNgMPrCrAB+4D
 WhQserDi4biW50SWLMWF/cvmM50IfdYmwMM1fHJi6Win29SkM1cDKAOb4HR4z5K1
 xvRDLnwHTz60nOWSEcvjVH68uJB/bRuQUjolw8hjRUmvU1Iv/PyMvQy8n0XYLsMn
 5AtMwUKFc16kdclvRWljRpBx2TUtthgHEDllpiK0Z/u0INMEYyxJ6sZAEr6VQWTR
 yIQyZHAx1vm3+b51MrLlJDETDaAVKO/bbw/jEDyR9wOGePW79al2HTusBiCjaMbo
 5XdnpvSDv60c52nc72UlI7XqkttAYO9EpJwlwtv9WbZNdKIzlfCgJZumTG81GNo4
 tLsmcUnCPL4W1zUV//g0CEoaUtU3s95mW01sjf9GBCxbAhFtOTg0yNzXfRF0/sYz
 ekMPePOQw5MinCUaN4n8ACPDRkVI5HAvrGT2JfQ85Hgyz+yIwSCjLrsTeOb/LjEs
 qHgyRy6drkUkgzlfdTqy
 =kzWH
 -----END PGP SIGNATURE-----

Merge tag 'hwmon-for-v5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging

Pull hwmon fixes from Guenter Roeck:
 "Minor fixes/regressions"

* tag 'hwmon-for-v5.0-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging:
  hwmon: (tmp421) Correct the misspelling of the tmp442 compatible attribute in OF device ID table
  hwmon: (occ) Fix potential integer overflow
  hwmon: (lm80) Fix missing unlock on error in set_fan_div()
  hwmon: (nct6775) Enable IO mapping for NCT6797D and NCT6798D
  hwmon: (nct6775) Fix chip ID for NCT6798D
2019-01-18 16:55:49 +12:00
Dave Airlie df0219b4f9 drm-misc-fixes for v5.0-rc3:
- Add missing calls to of_node_put to sun4i, meson, and rockchip.
 - Drop unimplemented prime callbacks in virtio and qxl, so support
   for prime is not advertised on those drivers.
 - Fix mode switching regression in meson.
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEuXvWqAysSYEJGuVH/lWMcqZwE8MFAlxAYYYACgkQ/lWMcqZw
 E8PfkBAAixwwfhomr9XxcKZutV7BU3rcaq4CKpZb9hD1SGlRCHxFeilVhsfizXKe
 t8XPrf1wD589XC76XwDH/4qXQNWm2C89C7SUNt0KUULmnREDY1dRwy/QZeHtNXBg
 DoEwCaOPa8/fJZNTZ+d0nkNgiXkdWMAWie+1Z4TZKoRJ6vVqweMi3zaSDcFEXi23
 +gzsm2ueZ6qxXGP6YXNsMOVQmyXDaRe4n8xn2iO2ixSztVeywUyoBV4jlepxr7c8
 nwJwy0N7QUFI3QXlGezO7yBo1XZ6noeFfIAnDVL6U+zaDui1yjvJ0oYM5+nL1P8P
 HgolR96xJOYk9QA7uqPDA+c/w2DCaQ/VlxVaGZYXYh+oE7tpQCKKeTA7pUSMGFqR
 1FnigdQCKIKv+SdF1Gh1BdfZnje6kfKDcPYsBhUPv9oB83FvAXII7hQj7ITykgLt
 ExVS/WDUIWnICruJdo0E7QpzQ2AMjQgkvS4wd94aOodSab0GRkSdrGEdH/YR+xGv
 wvNJKwslizUC995G61OjWsbRPWd9mAg9SD/wn2L5nPKgZZ8hBapViGtQpz7b3fWS
 J+GeYdchueCISxP2zqgnQCLwEWoXq26EXC3x+yEOWxzl/pV+HJMl70HGsrq7nflA
 9I9eA0gk9Nx38o76yMJ/CQCp2k9LCzRqFwQMtkw6h6ZmYWlrdng=
 =r2rK
 -----END PGP SIGNATURE-----

Merge tag 'drm-misc-fixes-2019-01-17' of git://anongit.freedesktop.org/drm/drm-misc into drm-fixes

drm-misc-fixes for v5.0-rc3:
- Add missing calls to of_node_put to sun4i, meson, and rockchip.
- Drop unimplemented prime callbacks in virtio and qxl, so support
  for prime is not advertised on those drivers.
- Fix mode switching regression in meson.

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/9af07312-f435-2fda-65a2-9fe92cdf5da4@linux.intel.com
2019-01-18 09:14:45 +10:00
Dave Airlie 4ac4cb70d1 drm/i915/gvt fixes for v5.0-rc3
-----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEFWWmW3ewYy4RJOWc05gHnSar7m8FAlxAVlYACgkQ05gHnSar
 7m/1/Q//ZwPlIUbWOS+PFklfoY9c0APwMWKzrnnDOxvnpA8KRsaY+yKn5FW91fcZ
 ee9S1fUlySuKVpsWLKhoiVM04tU+gQmO+UeGvNbMG1yTHIOq97sAP/cSIPnOuDkW
 2d1vSihmnx/RSuEgd9E+a8yMoIF+PtXKcSl4nUT4nurYPiUvC12nqS/C9sfF5JP0
 ZQc68ATj9wjJlhenAPjgsr6GP2YOzr9yqAQ1xV/PEg4Gth9uFM+dbbn+8vBOkjCt
 5fiB66cS8aGN5jwOlafqsMKjQeKHdV5bpJjpWirB9vdkiDHk/wOlzOUc2ySp0Krg
 1mJUL0KyWs6PfQvZvXCalQTOq9l6enCbq4N58/l4cC4LBU2Nx7LW7GwmHt9ONxjB
 aBQjTd2gku/DFyYHjCv7zAyHVLTu0TRWJpRlZGP5IpvECK21uFz8OtiiecoCvdm1
 bdQLr3cMXpT8JwLIr/N1lvMQTThFFvBCrnSruqbAikHFrZNkacczw7IqMUWQnsri
 SNTJ4s2hy6eThAIGGR61kXfnymKZ8GDKUYzi+De0OPaQ3VYFqaGQQk+1VkXpr0Qk
 S+r8oawzx5/FlDKZJqcDAXSaROcvFpbpVys+UozVp22lu/PPTwW0ReDG5uGQw/le
 tgEim6CnBj7wpDOZ4DOlH9npLbIvTrQ7M1HgjJ9DJ4DbNWu+R/s=
 =cHcP
 -----END PGP SIGNATURE-----

Merge tag 'drm-intel-fixes-2019-01-17' of git://anongit.freedesktop.org/drm/drm-intel into drm-fixes

drm/i915/gvt fixes for v5.0-rc3

"This contains one cmd parser failure fix to allow cmd access for one
register, and fix region cleanup properly in vGPU destroy, and another
fix for critical mmap size check mistake."

Signed-off-by: Dave Airlie <airlied@redhat.com>

From: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/87ef9bfusc.fsf@intel.com
2019-01-18 09:13:14 +10:00
Dave Airlie 586cdb0db7 Merge branch 'drm-fixes-5.0' of git://people.freedesktop.org/~agd5f/linux into drm-fixes
Fixes for 5.0:
- Fix KFD on ARM64
- Fix KFD topology with mixed APU and dGPU systems
- Powerplay fix for vega12
- DC Raven fixes
- Freesync fix

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Alex Deucher <alexdeucher@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190116224524.3314-1-alexander.deucher@amd.com
2019-01-18 09:10:21 +10:00
Kangjie Lu 248b57015f leds: lp5523: fix a missing check of return value of lp55xx_read
When lp55xx_read() fails, "status" is an uninitialized variable and thus
may contain random value; using it leads to undefined behaviors.

The fix inserts a check for the return value of lp55xx_read: if it
fails, returns with its error code.

Signed-off-by: Kangjie Lu <kjlu@umn.edu>
Signed-off-by: Jacek Anaszewski <jacek.anaszewski@gmail.com>
2019-01-17 22:27:39 +01:00
Cheng-Min Ao f422449b58 hwmon: (tmp421) Correct the misspelling of the tmp442 compatible attribute in OF device ID table
Correct a typo in OF device ID table
The last one should be 'ti,tmp442'

Signed-off-by: Cheng-Min Ao <tony_ao@wiwynn.com>
Signed-off-by: Yu-Hsiang Chen <matt_chen@wiwynn.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2019-01-17 12:54:52 -08:00
Linus Torvalds a3a80255d5 AFS fixes
-----BEGIN PGP SIGNATURE-----
 
 iQIVAwUAXECcyPu3V2unywtrAQIpGw//ctcGHg2sfUEra17pvlKEbpZe9bMeJxp6
 UY2YR5gPpiYMmvNe8hLl3I68b43h03jGOx+KmqowqX7anNq3o2nMy0pDbuGmKtuS
 5NmIOECAml8k2uPSpacAF2s6TsxB2lTDYwZdyeuRmZ4scOTujNby33RlijGIxX4s
 87WJFRuCacm9I1KkiKKn4PWoYGjDdsZ7rsDyEeBmQ/MiKOSLG4QP5XuNr4X9zFMX
 r8uF3N8h/NzJWefEirc2DPFfiWLJqkyclq9tgsTB1Z3l+x5u/MHnIg3rZpZhH0uC
 GhGWjlGYqTxOwzYCaOOsNIDRF4rAGPi3lzuJXjONnhvbOO7DCGJ+Mo2obxkAqLL6
 PrtFuQvgXIOl/k8y6AdckuPPu/OMHT1hyY0PQXmTGhHAAfPP3RHoPl7owEjmAbRg
 hvRkFDSIKZ4Kr1nKP4vwaJYEKtxUQrkOwZKmN6ve31ZeJsyrH12MsCgWvp7oQwRJ
 fVbk8DWVRtYzy4RaO3Xr+0WfD+03dDi6KKCPPiC2gtNKOO+1Kco/EtIqPi6SXg0m
 ee/mFOkRsmEh++iNxS58qLxH37On6GSYOElSIMN0NJDNA2TzLrvidXlMSOTD1hj4
 n6gL38E3br/CIimKPYm87qi6yC59CAtrJCulYiPOoMc20eaEUP4DIXN8yjgjLNQp
 Hj5M9GRTwXk=
 =cUrU
 -----END PGP SIGNATURE-----

Merge tag 'afs-fixes-20190117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull AFS fixes from David Howells:
 "Here's a set of fixes for AFS:

   - Use struct_size() for kzalloc() size calculation.

   - When calling YFS.CreateFile rather than AFS.CreateFile, it is
     possible to create a file with a file lock already held. The
     default value indicating no lock required is actually -1, not 0.

   - Fix an oops in inode/vnode validation if the target inode doesn't
     have a server interest assigned (ie. a server that will notify us
     of changes by third parties).

   - Fix refcounting of keys in file locking.

   - Fix a race in refcounting asynchronous operations in the event of
     an error during request transmission. The provision of a dedicated
     function to get an extra ref on a call is split into a separate
     commit"

* tag 'afs-fixes-20190117' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix race in async call refcounting
  afs: Provide a function to get a ref on a call
  afs: Fix key refcounting in file locking code
  afs: Don't set vnode->cb_s_break in afs_validate()
  afs: Set correct lock type for the yfs CreateFile
  afs: Use struct_size() in kzalloc()
2019-01-18 06:27:24 +12:00
Linus Torvalds 6d060fa390 Merge branch 'stable/for-linus-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb
Pull swiotlb fix from Konrad Rzeszutek Wilk:
 "A tiny fix for v5.0-rc2:

  This fixes an issue with GPU cards not working anymore with the DMA
  mapping work Christopher did - as the SWIOTLB is initialized first and
  then free'd (as IOMMU is available) but we forgot to clear our start
  and end entries which are used and BOOM"

* 'stable/for-linus-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
  swiotlb: clear io_tlb_start and io_tlb_end in swiotlb_exit
2019-01-18 06:22:08 +12:00
Linus Torvalds e4484a4955 Kbuild fixes for v5.0
- clean generated files in scripts/kconfig/ by 'make mrproper'
 
  - fix conflict between dead code elimination and ftrace for GCC <= 4.7
 
  - fix external module build with CONFIG_STACKPROTECTOR
 
  - remove unused code
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJcQJS3AAoJED2LAQed4NsGkxQP/jBhAKwA4UGUiMexS/yV5bMj
 nb4uvZkRvd/3uoKChCZ0ljFg3SU+qevmmOG+hkqVfictM/ilinI4+3IrHvFWKJ8K
 lKG7BfYJRO0Af2cJ+7rlT5C8hSDRK8C3R43mfy1L6QR8LjqBU/u7ORs0fPPXbdJN
 Rr99UZgM1VUmaqfVRxtujM9jogihGjDSGElZ8a5dKe1tCjKjSlFr5I9VdTxthJR0
 6qVl1RE/+lgO5iiAdI0DRKmnq4jtK5hQU4+2EL/Ir0FAJORZ7Kp6ilh7UVAMislk
 rF/91f7rpDafDZnx7SzoP+sdPuiyT1vygzSbjLbFVZ4iXBZMjtRqdmYmWMTknKZQ
 KjqqoYXSCwgD4tVJg4CD8USnrFHPBEhLGGhI7tH2lcuRJT8d0xPkfXTmqT+2QOIs
 ETF3r0mwbV7tqjwVbGHBJ+SBI1HZ9s00kxzg6coTnkl6GQPSs0FWxUJhhOWF1jzB
 G2+sT/AhqjsuuJndF8jgLwcd+ncrzO5V1wNrbv5LQ49smwRddiE3tVCXy0NV5pQD
 pqaDybt8MQfOGrWsf6xDbrKXy4a1tVcxrFCERU8Ihw8/Q4Vvr9bLqaGt05CtVwgi
 lj7enlRJmRpz5B1ZvGRttYWRycKP8V+rsMKJmPdrdwxul6FC+QpGV9Cdnt87vbK0
 P+512kpmGJX4oe3BOaww
 =16cD
 -----END PGP SIGNATURE-----

Merge tag 'kbuild-fixes-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - clean generated files in scripts/kconfig/ by 'make mrproper'

 - fix conflict between dead code elimination and ftrace for GCC <= 4.7

 - fix external module build with CONFIG_STACKPROTECTOR

 - remove unused code

* tag 'kbuild-fixes-v5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: mark prepare0 as PHONY to fix external module build
  openrisc: remove unneeded code in arch/openrisc/Makefile
  nds32: remove unneeded code in arch/nds32/Makefile
  ia64: remove redundant 'export AWK'
  kbuild: remove unused archmrproper
  kbuild: remove unused baseprereq
  kbuild: Disable LD_DEAD_CODE_DATA_ELIMINATION with ftrace & GCC <= 4.7
  kconfig: clean generated *conf-cfg files
2019-01-18 06:20:09 +12:00
Linus Torvalds d471c4dfa1 Devicetree fixes for v5.0:
- Remove now unused struct device_node.type pointer
 
 - Fix meson-axg reset header SPDX tag
 
 - Add missing of_node_put in of_graph_get_remote_port_parent
 
 - Fix several binding doc file references and typos
 -----BEGIN PGP SIGNATURE-----
 
 iQJEBAABCgAuFiEEktVUI4SxYhzZyEuo+vtdtY28YcMFAlw/fpIQHHJvYmhAa2Vy
 bmVsLm9yZwAKCRD6+121jbxhw1QHD/9Qd6HF6S0hGIyYhcIDjJPRKLpQaMGeOToc
 MqUXF+UnK4QajMo8spmhYsSQmkzg0TXEDkc9DxVF0Jw9sluho+c9vdycxwmf6DqU
 VF2x1tVqWMOfgcBBCLWkC3pHeq98JQfwEnFVUWKjYpanFN7Y5G9GMnBnkQAfUJ62
 pW7ScprcWa9xKNdWXbf9cas7RF4YAaoLcxrWaAZTbx/c0DaDl5taA4w2Vule6PfU
 v9V4fstaemxwVsXdkLxmsfsdI9RsBNFYvePA0D1E7rAZ2n6FnYrlfdYDN4ZYXepu
 8CXBgONA26hq1/K/m7sulRZoeAZ4rU82ytF+bOOq8BhTdveAydqPfwk3j7D3edkp
 Jh93KaqBbyZ9MUdf7dbvl5camct/Nj/8fVB77cZkE3TDLHZRp3M8OW/S4RrQ+34e
 Xecuofz1Xb6YL2Fk69UI7AE/RhWMzGTpq74wWgqQ+CHb4CyjJ2l5NI2pWW7YnKFa
 VzOi7ws7KUfHp3slJHf+dAAp01yYmA4nKL5iOBeqv8kQHvZUrHgtxKCI3Ve97qeQ
 tm0gksdvvxVI4sOVOdXLfU3j9oB6+X7HnwihAWbIlCkvNQxrzXus+I9Z70qdUS3/
 gGOQaY4kx/hDk2ucEUUitIDdoMSnx/dovHS/nMN/zS5APePigCVRDSOV3YejW2Gm
 2iwU22AJYw==
 =tHMW
 -----END PGP SIGNATURE-----

Merge tag 'devicetree-fixes-for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux

Pull Devicetree fixes from Rob Herring:

 - Remove now unused struct device_node.type pointer

 - Fix meson-axg reset header SPDX tag

 - Add missing of_node_put in of_graph_get_remote_port_parent

 - Fix several binding doc file references and typos

* tag 'devicetree-fixes-for-5.0' of git://git.kernel.org/pub/scm/linux/kernel/git/robh/linux:
  dt-bindings: reset: meson-axg: fix SPDX license id
  dt-bindings: soc: qcom: Fix trivial language typos
  doc: gpio-mvebu: fix broken reference to cp110-system-controller0.txt file
  OF: properties: add missing of_node_put
  doc: bindings: fix bad reference to ARM CPU bindings
  dt-bindings: marvell,mmp2: fix typos in bindings doc
  of: Remove struct device_node.type pointer
2019-01-18 06:15:28 +12:00
David Howells 34fa47612b afs: Fix race in async call refcounting
There's a race between afs_make_call() and afs_wake_up_async_call() in the
case that an error is returned from rxrpc_kernel_send_data() after it has
queued the final packet.

afs_make_call() will try and clean up the mess, but the call state may have
been moved on thereby causing afs_process_async_call() to also try and to
delete the call.

Fix this by:

 (1) Getting an extra ref for an asynchronous call for the call itself to
     hold.  This makes sure the call doesn't evaporate on us accidentally
     and will allow the call to be retained by the caller in a future
     patch.  The ref is released on leaving afs_make_call() or
     afs_wait_for_call_to_complete().

 (2) In the event of an error from rxrpc_kernel_send_data():

     (a) Don't set the call state to AFS_CALL_COMPLETE until *after* the
     	 call has been aborted and ended.  This prevents
     	 afs_deliver_to_call() from doing anything with any notifications
     	 it gets.

     (b) Explicitly end the call immediately to prevent further callbacks.

     (c) Cancel any queued async_work and wait for the work if it's
     	 executing.  This allows us to be sure the race won't recur when we
     	 change the state.  We put the work queue's ref on the call if we
     	 managed to cancel it.

     (d) Put the call's ref that we got in (1).  This belongs to us as long
     	 as the call is in state AFS_CALL_CL_REQUESTING.

Fixes: 341f741f04 ("afs: Refcount the afs_call struct")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17 15:17:28 +00:00
David Howells 7a75b0079a afs: Provide a function to get a ref on a call
Provide a function to get a reference on an afs_call struct.

Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17 15:17:28 +00:00
David Howells 59d49076ae afs: Fix key refcounting in file locking code
Fix the refcounting of the authentication keys in the file locking code.
The vnode->lock_key member points to a key on which it expects to be
holding a ref, but it isn't always given an extra ref, however.

Fixes: 0fafdc9f88 ("afs: Fix file locking")
Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17 15:17:28 +00:00
Marc Dionne 4882a27cec afs: Don't set vnode->cb_s_break in afs_validate()
A cb_interest record is not necessarily attached to the vnode on entry to
afs_validate(), which can cause an oops when we try to bring the vnode's
cb_s_break up to date in the default case (ie. no current callback promise
and the vnode has not been deleted).

Fix this by simply removing the line, as vnode->cb_s_break will be set when
needed by afs_register_server_cb_interest() when we next get a callback
promise from RPC call.

The oops looks something like:

    BUG: unable to handle kernel NULL pointer dereference at 0000000000000018
    ...
    RIP: 0010:afs_validate+0x66/0x250 [kafs]
    ...
    Call Trace:
     afs_d_revalidate+0x8d/0x340 [kafs]
     ? __d_lookup+0x61/0x150
     lookup_dcache+0x44/0x70
     ? lookup_dcache+0x44/0x70
     __lookup_hash+0x24/0xa0
     do_unlinkat+0x11d/0x2c0
     __x64_sys_unlink+0x23/0x30
     do_syscall_64+0x4d/0xf0
     entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: ae3b7361dc ("afs: Fix validation/callback interaction")
Signed-off-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
2019-01-17 15:15:52 +00:00
Masahiro Yamada e00d888048 kbuild: mark prepare0 as PHONY to fix external module build
Commit c3ff2a5193 ("powerpc/32: add stack protector support")
caused kernel panic on PowerPC when an external module is used with
CONFIG_STACKPROTECTOR because the 'prepare' target was not executed
for the external module build.

Commit e07db28eea ("kbuild: fix single target build for external
module") turned it into a build error because the 'prepare' target is
now executed but the 'prepare0' target is missing for the external
module build.

External module on arm/arm64 with CONFIG_STACKPROTECTOR_PER_TASK is
also broken in the same way.

Move 'PHONY += prepare0' to the common place. GNU Make is fine with
missing rule for phony targets. I also removed the comment which is
wrong irrespective of this commit.

I minimize the change so it can be easily backported to 4.20.x

To fix v4.20, please backport e07db28eea ("kbuild: fix single target
build for external module"), and then this commit.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=201891
Fixes: e07db28eea ("kbuild: fix single target build for external module")
Fixes: c3ff2a5193 ("powerpc/32: add stack protector support")
Fixes: 189af46571 ("ARM: smp: add support for per-task stack canaries")
Fixes: 0a1213fa74 ("arm64: enable per-task stack canaries")
Cc: linux-stable <stable@vger.kernel.org> # v4.20
Reported-by: Samuel Holland <samuel@sholland.org>
Reported-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
2019-01-17 23:42:59 +09:00