linux-stable.git/drivers/base/power, branch v4.1.43

PM / QoS: return -EINVAL for bogus strings

2017-07-31T17:37:55+00:00

[ Upstream commit 2ca30331c156ca9e97643ad05dd8930b8fe78b01 ]

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 
Cc: 3.15+  # 3.15+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

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

2017-06-26T02:02:20+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

PM / sleep: Handle failures in device_suspend_late() consistently

2016-06-06T23:12:32+00:00

[ Upstream commit 3a17fb329da68cb00558721aff876a80bba2fdb9 ]

Grygorii Strashko reports:

 The PM runtime will be left disabled for the device if its
 .suspend_late() callback fails and async suspend is not allowed
 for this device. In this case device will not be added in
 dpm_late_early_list and dpm_resume_early() will ignore this
 device, as result PM runtime will be disabled for it forever
 (side effect: after 8 subsequent failures for the same device
 the PM runtime will be reenabled due to disable_depth overflow).

To fix this problem, add devices to dpm_late_early_list regardless
of whether or not device_suspend_late() returns errors for them.

That will ensure failures in there to be handled consistently for
all devices regardless of their async suspend/resume status.

Reported-by: Grygorii Strashko 
Tested-by: Grygorii Strashko 
Signed-off-by: Rafael J. Wysocki 
Cc: All applicable 
Signed-off-by: Sasha Levin

PM / Runtime: Fix error path in pm_runtime_force_resume()

2016-06-03T23:15:31+00:00

[ Upstream commit 0ae3aeefabbeef26294e7a349b51f1c761d46c9f ]

As pm_runtime_set_active() may fail because the device's parent isn't
active, we can end up executing the ->runtime_resume() callback for the
device when it isn't allowed.

Fix this by invoking pm_runtime_set_active() before running the callback
and let's also deal with the error code.

Fixes: 37f204164dfb (PM: Add pm_runtime_suspend|resume_force functions)
Signed-off-by: Ulf Hansson 
Reviewed-by: Linus Walleij 
Cc: 3.15+  # 3.15+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM / clk: don't return int on __pm_clk_enable()

2015-09-21T17:05:31+00:00

commit f4745a92781b872455f32feb01d1dce92aefcb6c upstream.

Static analysis by cppcheck found an issue that was recently introduced by
commit 471f7707b6f0b1 ("PM / clock_ops: make __pm_clk_enable more generic")
where a return status in ret was not being initialised and garbage
being returned when ce->status >= PCE_STATUS_ERROR.

The fact that ret is not being checked by the caller and that
ret is only used internally __pm_clk_enable() to check if clk_enable()
was OK means we can ignore returning it instead turn
__pm_clk_enable() into function with a void return.

Fixes: 471f7707b6f0b1 ("PM / clock_ops: make __pm_clk_enable more generic")
Signed-off-by: Colin Ian King 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM / clk: Fix clock error check in __pm_clk_add()

2015-08-03T16:29:15+00:00

commit 3fc3a0be0dab352e065d1dad7d3f81953ed0d4bc upstream.

In the final iteration of commit 245bd6f6af8a62a2 ("PM / clock_ops: Add
pm_clk_add_clk()"), a refcount increment was added by Grygorii Strashko.
However, the accompanying IS_ERR() check operates on the wrong clock
pointer, which is always zero at this point, i.e. not an error.
This may lead to a NULL pointer dereference later, when __clk_get()
tries to dereference an error pointer.

Check the passed clock pointer instead to fix this.

Signed-off-by: Geert Uytterhoeven 
Fixes: 245bd6f6af8a62a2 ("PM / clock_ops: Add pm_clk_add_clk()")
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

power: wakeup: remove use of seq_printf return value

2015-04-15T23:35:24+00:00

The seq_printf return value, because it's frequently misused,
will eventually be converted to void.

See: commit 1f33c41c03da ("seq_file: Rename seq_overflow() to
     seq_has_overflowed() and make public")

Signed-off-by: Joe Perches 
Cc: "Rafael J. Wysocki" 
Cc: Pavel Machek 
Cc: Len Brown 
Cc: Greg Kroah-Hartman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

Merge branches 'pm-sleep' and 'pm-domains'

2015-04-12T22:37:13+00:00

* pm-sleep:
  PM / watchdog: iTCO: stop watchdog during system suspend
  PM / sleep: add pm-trace support for suspending phase
  PM / sleep: add configurable delay for pm_test

* pm-domains:
  PM / domains: avoid potential oops in pm_genpd_remove_device()
  PM / domains: factor out code to get the generic PM domain from a struct device
  PM / domains: quieten down generic pm domains
  PM / Domains: Sync runtime PM status with genpd after probe
  driver core / PM: Add PM domain callbacks for device setup/cleanup
  MAINTAINERS: add entry for Generic PM domains (genpd)

Merge back earlier suspend/hibernate material for v4.1.

2015-04-10T10:01:59+00:00

PM / domains: avoid potential oops in pm_genpd_remove_device()

2015-03-23T22:20:28+00:00

pm_genpd_remove_device() tries hard to validate the generic PM domain
passed to it, but the validation is not complete.

dev->pm_domain contains a struct dev_pm_domain, which is the "base
class" of generic PM domains.  Other users of dev_pm_domains include
stuff like vga_switheroo.  Hence, a device could have a generic PM
domain or a vga_switcheroo PM domain in dev->pm_domain.

We need ot be certain that the PM domain is actually valid before we
try to remove it.  We can do this easily as we have a way to get the
current validated generic PM domain for a struct device.  This must
match the generic PM domain being requested for removal.

Convert the code to use this alternative validation method instead.

Signed-off-by: Russell King 
Acked-by: Kevin Hilman 
Acked-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki