Pull scheduler fixes from Ingo Molnar:
"A deadline scheduler warning/race fix, and a cfs_period_us quota
calculation workaround where the real fix looks too involved to merge
immediately"

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/deadline: Correctly handle active 0-lag timers
sched/fair: Limit sched_cfs_period_timer() loop to avoid hard lockup

Pull locking fixes from Ingo Molnar:
"A lockdep warning fix and a script execution fix when atomics are
generated"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomics: Don't assume that scripts are executable
locking/lockdep: Make lockdep_unregister_key() honor 'debug_locks' again

syzbot reported the following warning:

[ ] WARNING: CPU: 4 PID: 17089 at kernel/sched/deadline.c:255 task_non_contending+0xae0/0x1950

line 255 of deadline.c is:

WARN_ON(hrtimer_active(&dl_se->inactive_timer));

in task_non_contending().

Unfortunately, in some cases (for example, a deadline task
continuosly blocking and waking immediately) it can happen that
a task blocks (and task_non_contending() is called) while the
0-lag timer is still active.

In this case, the safest thing to do is to immediately decrease
the running bandwidth of the task, without trying to re-arm the 0-lag timer.

Signed-off-by: luca abeni <luca.abeni@santannapisa.it>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: chengjian (D) <cj.chengjian@huawei.com>
Link: https://lkml.kernel.org/r/20190325131530.34706-1-luca.abeni@santannapisa.it
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull cgroup fix from Tejun Heo:
"A patch to fix a RCU imbalance error in the devices cgroup
configuration error path"

* 'for-5.1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
device_cgroup: fix RCU imbalance in error case

patch(1) doesn't set the x bit on files. So if someone downloads and
applies patch-4.21.xz, their kernel won't build. Fix that by executing
/bin/sh.

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>

With extremely short cfs_period_us setting on a parent task group with a large
number of children the for loop in sched_cfs_period_timer() can run until the
watchdog fires. There is no guarantee that the call to hrtimer_forward_now()
will ever return 0. The large number of children can make
do_sched_cfs_period_timer() take longer than the period.

NMI watchdog: Watchdog detected hard LOCKUP on cpu 24
RIP: 0010:tg_nop+0x0/0x10
<IRQ>
walk_tg_tree_from+0x29/0xb0
unthrottle_cfs_rq+0xe0/0x1a0
distribute_cfs_runtime+0xd3/0xf0
sched_cfs_period_timer+0xcb/0x160
? sched_cfs_slack_timer+0xd0/0xd0
__hrtimer_run_queues+0xfb/0x270
hrtimer_interrupt+0x122/0x270
smp_apic_timer_interrupt+0x6a/0x140
apic_timer_interrupt+0xf/0x20
</IRQ>

To prevent this we add protection to the loop that detects when the loop has run
too many times and scales the period and quota up, proportionally, so that the timer
can complete before then next period expires. This preserves the relative runtime
quota while preventing the hard lockup.

A warning is issued reporting this state and the new values.

Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190319130005.25492-1-pauld@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull percpu fixlet from Dennis Zhou:
"This stops printing the base address of percpu memory on
initialization"

* 'for-5.1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/dennis/percpu:
percpu: stop printing kernel addresses

When dev_exception_add() returns an error (due to a failed memory
allocation), make sure that we move the RCU preemption count back to where
it was before we were called. We dropped the RCU read lock inside the loop
body, so we can't just "break".

sparse complains about this, too:

$ make -s C=2 security/device_cgroup.o
./include/linux/rcupdate.h:647:9: warning: context imbalance in
'propagate_exception' - unexpected unlock

Fixes: d591fb56618f ("device_cgroup: simplify cgroup tree walk in propagate_exception()")
Cc: stable@vger.kernel.org
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

If lockdep_register_key() and lockdep_unregister_key() are called with
debug_locks == false then the following warning is reported:

WARNING: CPU: 2 PID: 15145 at kernel/locking/lockdep.c:4920 lockdep_unregister_key+0x1ad/0x240

That warning is reported because lockdep_unregister_key() ignores the
value of 'debug_locks' and because the behavior of lockdep_register_key()
depends on whether or not 'debug_locks' is set. Fix this inconsistency
by making lockdep_unregister_key() take 'debug_locks' again into
account.

Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: shenghui <shhuiw@foxmail.com>
Fixes: 90c1cba2b3b3 ("locking/lockdep: Zap lock classes even with lock debugging disabled")
Link: http://lkml.kernel.org/r/20190415170538.23491-1-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>

Pull libnvdimm fixes from Dan Williams:
"I debated holding this back for the v5.2 merge window due to the size
of the "zero-key" changes, but affected users would benefit from
having the fixes sooner. It did not make sense to change the zero-key
semantic in isolation for the "secure-erase" command, but instead
include it for all security commands.

The short background on the need for these changes is that some NVDIMM
platforms enable security with a default zero-key rather than let the
OS specify the initial key. This makes the security enabling that
landed in v5.0 unusable for some users.

Summary:

- Compatibility fix for nvdimm-security implementations with a
default zero-key.

- Miscellaneous small fixes for out-of-bound accesses, cleanup after
initialization failures, and missing debug messages"

* tag 'libnvdimm-fixes-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
tools/testing/nvdimm: Retain security state after overwrite
libnvdimm/pmem: fix a possible OOB access when read and write pmem
libnvdimm/security, acpi/nfit: unify zero-key for all security commands
libnvdimm/security: provide fix for secure-erase to use zero-key
libnvdimm/btt: Fix a kmemdup failure check
libnvdimm/namespace: Fix a potential NULL pointer dereference
acpi/nfit: Always dump _DSM output payload

Pull tty/serial fixes from Greg KH:
"Here are five small fixes for some tty/serial/vt issues that have been
reported.

The vt one has been around for a while, it is good to finally get that
resolved. The others fix a build warning that showed up in 5.1-rc1,
and resolve a problem in the sh-sci driver.

Note, the second patch for build warning fix for the sc16is7xx driver
was just applied to the tree, as it resolves a problem with the
previous patch to try to solve the issue. It has not shown up in
linux-next yet, unlike all of the other patches, but it has passed
0-day testing and everyone seems to agree that it is correct"

* tag 'tty-5.1-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
sc16is7xx: put err_spi and err_i2c into correct #ifdef
vt: fix cursor when clearing the screen
sc16is7xx: move label 'err_spi' to correct section
serial: sh-sci: Fix HSCIF RX sampling point adjustment
serial: sh-sci: Fix HSCIF RX sampling point calculation

Since commit ad67b74d2469d9b8 ("printk: hash addresses printed with %p"),
at boot "____ptrval____" is printed instead of actual addresses:

percpu: Embedded 38 pages/cpu @(____ptrval____) s124376 r0 d31272 u524288

Instead of changing the print to "%px", and leaking kernel addresses,
just remove the print completely, cfr. e.g. commit 071929dbdd865f77
("arm64: Stop printing the virtual memory layout").

Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Dennis Zhou <dennis@kernel.org>