linux-toradex.git/drivers/base/power, branch v4.9.49

PM / Domains: defer dev_pm_domain_set() until genpd->attach_dev succeeds if present

2017-07-27T22:08:08+00:00

commit 975e83cfb8dc16e7a2fdc58188c77c0c605876c2 upstream.

If the genpd->attach_dev or genpd->power_on fails, genpd_dev_pm_attach
may return -EPROBE_DEFER initially. However genpd_alloc_dev_data sets
the PM domain for the device unconditionally.

When subsequent attempts are made to call genpd_dev_pm_attach, it may
return -EEXISTS checking dev->pm_domain without re-attempting to call
attach_dev or power_on.

platform_drv_probe then attempts to call drv->probe as the return value
-EEXIST != -EPROBE_DEFER, which may end up in a situation where the
device is accessed without it's power domain switched on.

Fixes: f104e1e5ef57 (PM / Domains: Re-order initialization of generic_pm_domain_data)
Signed-off-by: Sudeep Holla 
Acked-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / Domains: Fix unsafe iteration over modified list of domains

2017-07-27T22:07:59+00:00

commit a7e2d1bce4c1db471f1cbc0c4666a3112bbf0994 upstream.

of_genpd_remove_last() iterates over list of domains and removes
matching element thus it has to use safe version of list iteration.

Fixes: 17926551c98a (PM / Domains: Add support for removing nested PM domains by provider)
Signed-off-by: Krzysztof Kozlowski 
Acked-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / Domains: Fix unsafe iteration over modified list of domain providers

2017-07-27T22:07:59+00:00

commit b556b15dc04e9b9b98790f04c21acf5e24f994b2 upstream.

of_genpd_del_provider() iterates over list of domain provides and
removes matching element thus it has to use safe version of list
iteration.

Fixes: aa42240ab254 (PM / Domains: Add generic OF-based PM domain look-up)
Signed-off-by: Krzysztof Kozlowski 
Acked-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / Domains: Fix unsafe iteration over modified list of device links

2017-07-27T22:07:58+00:00

commit c6e83cac3eda5f7dd32ee1453df2f7abb5c6cd46 upstream.

pm_genpd_remove_subdomain() iterates over domain's master_links list and
removes matching element thus it has to use safe version of list
iteration.

Fixes: f721889ff65a ("PM / Domains: Support for generic I/O PM domains (v8)")
Signed-off-by: Krzysztof Kozlowski 
Acked-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / QoS: return -EINVAL for bogus strings

2017-07-21T05:42:24+00:00

commit 2ca30331c156ca9e97643ad05dd8930b8fe78b01 upstream.

In the current code, if the user accidentally writes a bogus command to
this sysfs file, then we set the latency tolerance to an uninitialized
variable.

Fixes: 2d984ad132a8 (PM / QoS: Introcuce latency tolerance device PM QoS type)
Signed-off-by: Dan Carpenter 
Acked-by: Pavel Machek 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / wakeirq: Convert to SRCU

2017-07-21T05:42:24+00:00

commit ea0212f40c6bc0594c8eff79266759e3ecd4bacc upstream.

The wakeirq infrastructure uses RCU to protect the list of wakeirqs. That
breaks the irq bus locking infrastructure, which is allows sleeping
functions to be called so interrupt controllers behind slow busses,
e.g. i2c, can be handled.

The wakeirq functions hold rcu_read_lock and call into irq functions, which
in case of interrupts using the irq bus locking will trigger a
might_sleep() splat.

Convert the wakeirq infrastructure to Sleepable RCU and unbreak it.

Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling)
Reported-by: Brian Norris 
Suggested-by: Paul E. McKenney 
Signed-off-by: Thomas Gleixner 
Reviewed-by: Paul E. McKenney 
Tested-by: Tony Lindgren 
Tested-by: Brian Norris 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / runtime: Avoid false-positive warnings from might_sleep_if()

2017-06-17T04:41:51+00:00

[ Upstream commit a9306a63631493afc75893a4ac405d4e1cbae6aa ]

The might_sleep_if() assertions in __pm_runtime_idle(),
__pm_runtime_suspend() and __pm_runtime_resume() may generate
false-positive warnings in some situations.  For example, that
happens if a nested pm_runtime_get_sync()/pm_runtime_put() pair
is executed with disabled interrupts within an outer
pm_runtime_get_sync()/pm_runtime_put() section for the same device.
[Generally, pm_runtime_get_sync() may sleep, so it should not be
called with disabled interrupts, but in this particular case the
previous pm_runtime_get_sync() guarantees that the device will not
be suspended, so the inner pm_runtime_get_sync() will return
immediately after incrementing the device's usage counter.]

That started to happen in the i915 driver in 4.10-rc, leading to
the following splat:

 BUG: sleeping function called from invalid context at drivers/base/power/runtime.c:1032
 in_atomic(): 1, irqs_disabled(): 0, pid: 1500, name: Xorg
 1 lock held by Xorg/1500:
  #0:  (&dev->struct_mutex){+.+.+.}, at:
  [] i915_mutex_lock_interruptible+0x43/0x140 [i915]
 CPU: 0 PID: 1500 Comm: Xorg Not tainted
 Call Trace:
  dump_stack+0x85/0xc2
  ___might_sleep+0x196/0x260
  __might_sleep+0x53/0xb0
  __pm_runtime_resume+0x7a/0x90
  intel_runtime_pm_get+0x25/0x90 [i915]
  aliasing_gtt_bind_vma+0xaa/0xf0 [i915]
  i915_vma_bind+0xaf/0x1e0 [i915]
  i915_gem_execbuffer_relocate_entry+0x513/0x6f0 [i915]
  i915_gem_execbuffer_relocate_vma.isra.34+0x188/0x250 [i915]
  ? trace_hardirqs_on+0xd/0x10
  ? i915_gem_execbuffer_reserve_vma.isra.31+0x152/0x1f0 [i915]
  ? i915_gem_execbuffer_reserve.isra.32+0x372/0x3a0 [i915]
  i915_gem_do_execbuffer.isra.38+0xa70/0x1a40 [i915]
  ? __might_fault+0x4e/0xb0
  i915_gem_execbuffer2+0xc5/0x260 [i915]
  ? __might_fault+0x4e/0xb0
  drm_ioctl+0x206/0x450 [drm]
  ? i915_gem_execbuffer+0x340/0x340 [i915]
  ? __fget+0x5/0x200
  do_vfs_ioctl+0x91/0x6f0
  ? __fget+0x111/0x200
  ? __fget+0x5/0x200
  SyS_ioctl+0x79/0x90
  entry_SYSCALL_64_fastpath+0x23/0xc6

even though the code triggering it is correct.

Unfortunately, the might_sleep_if() assertions in question are
too coarse-grained to cover such cases correctly, so make them
a bit less sensitive in order to avoid the false-positives.

Reported-and-tested-by: Sedat Dilek 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

PM / wakeirq: Fix dedicated wakeirq for drivers not using autosuspend

2017-01-12T10:39:31+00:00

commit bed570307ed78f21b77cb04a1df781dee4a8f05a upstream.

I noticed some wakeirq flakeyness with consumer drivers not using
autosuspend. For drivers not using autosuspend, the wakeirq may never
get unmasked in rpm_suspend() because of irq desc->depth.

We are configuring dedicated wakeirqs to start with IRQ_NOAUTOEN as we
naturally don't want them running until rpm_suspend() is called.

However, when a consumer driver initially calls pm_runtime_get(), we
now wrongly start with disable_irq_nosync() call on the dedicated
wakeirq that is disabled to start with.

This causes desc->depth to toggle between 1 and 2 instead of the usual
0 and 1. This can prevent enable_irq() from unmasking the wakeirq as
that only happens at desc->depth 1.

This does not necessarily show up with drivers using autosuspend as
there is time for disable_irq_nosync() before rpm_suspend() gets called
after the autosuspend timeout.

Let's fix the issue by adding wirq->status that lazily gets set on
the first rpm_suspend(). We also need PM runtime core private functions
for dev_pm_enable_wake_irq_check() and dev_pm_disable_wake_irq_check()
so we can enable the dedicated wakeirq on the first rpm_suspend().

While at it, let's also fix the comments for dev_pm_enable_wake_irq()
and dev_pm_disable_wake_irq(). Those can still be used by the consumer
drivers as needed because the IRQ core manages the interrupt usecount
for us.

Fixes: 4990d4fe327b (PM / Wakeirq: Add automated device wake IRQ handling)
Signed-off-by: Tony Lindgren 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Don't use OPP structure outside of rcu protected section

2017-01-06T09:40:15+00:00

commit dc39d06fcd7a4a82d72eae7b71e94e888b96d29e upstream.

The OPP structure must not be used out of the rcu protected section.
Cache the values to be used in separate variables instead.

Signed-off-by: Viresh Kumar 
Reviewed-by: Stephen Boyd 
Tested-by: Dave Gerlach 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / OPP: Pass opp_table to dev_pm_opp_put_regulator()

2017-01-06T09:40:15+00:00

commit 91291d9ad92faa65a56a9a19d658d8049b78d3d4 upstream.

Joonyoung Shim reported an interesting problem on his ARM octa-core
Odoroid-XU3 platform. During system suspend, dev_pm_opp_put_regulator()
was failing for a struct device for which dev_pm_opp_set_regulator() is
called earlier.

This happened because an earlier call to
dev_pm_opp_of_cpumask_remove_table() function (from cpufreq-dt.c file)
removed all the entries from opp_table->dev_list apart from the last CPU
device in the cpumask of CPUs sharing the OPP.

But both dev_pm_opp_set_regulator() and dev_pm_opp_put_regulator()
routines get CPU device for the first CPU in the cpumask. And so the OPP
core failed to find the OPP table for the struct device.

This patch attempts to fix this problem by returning a pointer to the
opp_table from dev_pm_opp_set_regulator() and using that as the
parameter to dev_pm_opp_put_regulator(). This ensures that the
dev_pm_opp_put_regulator() doesn't fail to find the opp table.

Note that similar design problem also exists with other
dev_pm_opp_put_*() APIs, but those aren't used currently by anyone and
so we don't need to update them for now.

Reported-by: Joonyoung Shim 
Signed-off-by: Stephen Boyd 
Signed-off-by: Viresh Kumar 
[ Viresh: Wrote commit log and tested on exynos 5250 ]
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman