linux-stable.git/kernel, branch v5.2.11

genirq: Properly pair kobject_del() with kobject_add()

2019-08-29T06:30:25+00:00

commit d0ff14fdc987303aeeb7de6f1bd72c3749ae2a9b upstream.

If alloc_descs() fails before irq_sysfs_init() has run, free_desc() in the
cleanup path will call kobject_del() even though the kobject has not been
added with kobject_add().

Fix this by making the call to kobject_del() conditional on whether
irq_sysfs_init() has run.

This problem surfaced because commit aa30f47cf666 ("kobject: Add support
for default attribute groups to kobj_type") makes kobject_del() stricter
about pairing with kobject_add(). If the pairing is incorrrect, a WARNING
and backtrace occur in sysfs_remove_group() because there is no parent.

[ tglx: Add a comment to the code and make it work with CONFIG_SYSFS=n ]

Fixes: ecb3f394c5db ("genirq: Expose interrupt information through sysfs")
Signed-off-by: Michael Kelley 
Signed-off-by: Thomas Gleixner 
Acked-by: Greg Kroah-Hartman 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1564703564-4116-1-git-send-email-mikelley@microsoft.com
Signed-off-by: Greg Kroah-Hartman

psi: get poll_work to run when calling poll syscall next time

2019-08-29T06:30:24+00:00

commit 7b2b55da1db10a5525460633ae4b6fb0be060c41 upstream.

Only when calling the poll syscall the first time can user receive
POLLPRI correctly.  After that, user always fails to acquire the event
signal.

Reproduce case:
 1. Get the monitor code in Documentation/accounting/psi.txt
 2. Run it, and wait for the event triggered.
 3. Kill and restart the process.

The question is why we can end up with poll_scheduled = 1 but the work
not running (which would reset it to 0).  And the answer is because the
scheduling side sees group->poll_kworker under RCU protection and then
schedules it, but here we cancel the work and destroy the worker.  The
cancel needs to pair with resetting the poll_scheduled flag.

Link: http://lkml.kernel.org/r/1566357985-97781-1-git-send-email-joseph.qi@linux.alibaba.com
Signed-off-by: Jason Xing 
Signed-off-by: Joseph Qi 
Reviewed-by: Caspar Zhang 
Reviewed-by: Suren Baghdasaryan 
Acked-by: Johannes Weiner 
Cc: Ingo Molnar 
Cc: Peter Zijlstra 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 
Signed-off-by: Greg Kroah-Hartman

sched/psi: Do not require setsched permission from the trigger creator

2019-08-29T06:30:15+00:00

[ Upstream commit 04e048cf09d7b5fc995817cdc5ae1acd4482429c ]

When a process creates a new trigger by writing into /proc/pressure/*
files, permissions to write such a file should be used to determine whether
the process is allowed to do so or not. Current implementation would also
require such a process to have setsched capability. Setting of psi trigger
thread's scheduling policy is an implementation detail and should not be
exposed to the user level. Remove the permission check by using _nocheck
version of the function.

Suggested-by: Nick Kralevich 
Signed-off-by: Suren Baghdasaryan 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: lizefan@huawei.com
Cc: mingo@redhat.com
Cc: akpm@linux-foundation.org
Cc: kernel-team@android.com
Cc: dennisszhou@gmail.com
Cc: dennis@kernel.org
Cc: hannes@cmpxchg.org
Cc: axboe@kernel.dk
Link: https://lkml.kernel.org/r/20190730013310.162367-1-surenb@google.com
Signed-off-by: Sasha Levin

sched/psi: Reduce psimon FIFO priority

2019-08-29T06:30:15+00:00

[ Upstream commit 14f5c7b46a41a595fc61db37f55721714729e59e ]

PSI defaults to a FIFO-99 thread, reduce this to FIFO-1.

FIFO-99 is the very highest priority available to SCHED_FIFO and
it not a suitable default; it would indicate the psi work is the
most important work on the machine.

Since Real-Time tasks will have pre-allocated memory and locked it in
place, Real-Time tasks do not care about PSI. All it needs is to be
above OTHER.

Signed-off-by: Peter Zijlstra (Intel) 
Acked-by: Johannes Weiner 
Tested-by: Suren Baghdasaryan 
Cc: Thomas Gleixner 
Signed-off-by: Sasha Levin

sched/deadline: Fix double accounting of rq/running bw in push & pull

2019-08-29T06:30:14+00:00

[ Upstream commit f4904815f97a934258445a8f763f6b6c48f007e7 ]

{push,pull}_dl_task() always calls {de,}activate_task() with .flags=0
which sets p->on_rq=TASK_ON_RQ_MIGRATING.

{push,pull}_dl_task()->{de,}activate_task()->{de,en}queue_task()->
{de,en}queue_task_dl() calls {sub,add}_{running,rq}_bw() since
p->on_rq==TASK_ON_RQ_MIGRATING.
So {sub,add}_{running,rq}_bw() in {push,pull}_dl_task() is
double-accounting for that task.

Fix it by removing rq/running bw accounting in [push/pull]_dl_task().

Fixes: 7dd778841164 ("sched/core: Unify p->on_rq updates")
Signed-off-by: Dietmar Eggemann 
Signed-off-by: Peter Zijlstra (Intel) 
Cc: Valentin Schneider 
Cc: Ingo Molnar 
Cc: Luca Abeni 
Cc: Daniel Bristot de Oliveira 
Cc: Juri Lelli 
Cc: Qais Yousef 
Link: https://lkml.kernel.org/r/20190802145945.18702-2-dietmar.eggemann@arm.com
Signed-off-by: Sasha Levin

dma-mapping: check pfn validity in dma_common_{mmap,get_sgtable}

2019-08-25T14:10:25+00:00

[ Upstream commit 66d7780f18eae0232827fcffeaded39a6a168236 ]

Check that the pfn returned from arch_dma_coherent_to_pfn refers to
a valid page and reject the mmap / get_sgtable requests otherwise.

Based on the arm implementation of the mmap and get_sgtable methods.

Signed-off-by: Christoph Hellwig 
Tested-by: Vignesh Raghavendra 
Signed-off-by: Sasha Levin

cpufreq: schedutil: Don't skip freq update when limits change

2019-08-25T14:10:21+00:00

commit 600f5badb78c316146d062cfd7af4a2cfb655baa upstream.

To avoid reducing the frequency of a CPU prematurely, we skip reducing
the frequency if the CPU had been busy recently.

This should not be done when the limits of the policy are changed, for
example due to thermal throttling. We should always get the frequency
within the new limits as soon as possible.

Trying to fix this by using only one flag, i.e. need_freq_update, can
lead to a race condition where the flag gets cleared without forcing us
to change the frequency at least once. And so this patch introduces
another flag to avoid that race condition.

Fixes: ecd288429126 ("cpufreq: schedutil: Don't set next_freq to UINT_MAX")
Cc: v4.18+  # v4.18+
Reported-by: Doug Smythies 
Tested-by: Doug Smythies 
Signed-off-by: Viresh Kumar 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

perf/core: Fix creating kernel counters for PMUs that override event->cpu

2019-08-16T08:11:07+00:00

[ Upstream commit 4ce54af8b33d3e21ca935fc1b89b58cbba956051 ]

Some hardware PMU drivers will override perf_event.cpu inside their
event_init callback. This causes a lockdep splat when initialized through
the kernel API:

 WARNING: CPU: 0 PID: 250 at kernel/events/core.c:2917 ctx_sched_out+0x78/0x208
 pc : ctx_sched_out+0x78/0x208
 Call trace:
  ctx_sched_out+0x78/0x208
  __perf_install_in_context+0x160/0x248
  remote_function+0x58/0x68
  generic_exec_single+0x100/0x180
  smp_call_function_single+0x174/0x1b8
  perf_install_in_context+0x178/0x188
  perf_event_create_kernel_counter+0x118/0x160

Fix this by calling perf_install_in_context with event->cpu, just like
perf_event_open

Signed-off-by: Leonard Crestez 
Signed-off-by: Peter Zijlstra (Intel) 
Reviewed-by: Mark Rutland 
Cc: Alexander Shishkin 
Cc: Arnaldo Carvalho de Melo 
Cc: Frank Li 
Cc: Jiri Olsa 
Cc: Linus Torvalds 
Cc: Namhyung Kim 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: Will Deacon 
Link: https://lkml.kernel.org/r/c4ebe0503623066896d7046def4d6b1e06e0eb2e.1563972056.git.leonard.crestez@nxp.com
Signed-off-by: Ingo Molnar 
Signed-off-by: Sasha Levin

genirq/affinity: Create affinity mask for single vector

2019-08-16T08:10:56+00:00

commit 491beed3b102b6e6c0e7734200661242226e3933 upstream.

Since commit c66d4bd110a1f8 ("genirq/affinity: Add new callback for
(re)calculating interrupt sets"), irq_create_affinity_masks() returns
NULL in case of single vector. This change has caused regression on some
drivers, such as lpfc.

The problem is that single vector requests can happen in some generic cases:

  1) kdump kernel

  2) irq vectors resource is close to exhaustion.

If in that situation the affinity mask for a single vector is not created,
every caller has to handle the special case.

There is no reason why the mask cannot be created, so remove the check for
a single vector and create the mask.

Fixes: c66d4bd110a1f8 ("genirq/affinity: Add new callback for (re)calculating interrupt sets")
Signed-off-by: Ming Lei 
Signed-off-by: Thomas Gleixner 
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190805011906.5020-1-ming.lei@redhat.com
Signed-off-by: Greg Kroah-Hartman

fgraph: Remove redundant ftrace_graph_notrace_addr() test

2019-08-06T17:08:15+00:00

commit 6c77221df96177da0520847ce91e33f539fb8b2d upstream.

We already have tested it before. The second one should be removed.
With this change, the performance should have little improvement.

Link: http://lkml.kernel.org/r/20190730140850.7927-1-changbin.du@gmail.com

Cc: stable@vger.kernel.org
Fixes: 9cd2992f2d6c ("fgraph: Have set_graph_notrace only affect function_graph tracer")
Signed-off-by: Changbin Du 
Signed-off-by: Steven Rostedt (VMware) 
Signed-off-by: Greg Kroah-Hartman