<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/base/power, branch linux-4.8.y</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>PM / OPP: Pass opp_table to dev_pm_opp_put_regulator()</title>
<updated>2017-01-06T10:16:23+00:00</updated>
<author>
<name>Stephen Boyd</name>
<email>sboyd@codeaurora.org</email>
</author>
<published>2016-11-30T10:51:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e3742a15d6cdad8a22cea66feb3ad44618085072'/>
<id>e3742a15d6cdad8a22cea66feb3ad44618085072</id>
<content type='text'>
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-&gt;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 &lt;jy0922.shim@samsung.com&gt;
Signed-off-by: Stephen Boyd &lt;sboyd@codeaurora.org&gt;
Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
[ Viresh: Wrote commit log and tested on exynos 5250 ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
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-&gt;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 &lt;jy0922.shim@samsung.com&gt;
Signed-off-by: Stephen Boyd &lt;sboyd@codeaurora.org&gt;
Signed-off-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
[ Viresh: Wrote commit log and tested on exynos 5250 ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>PM / sleep: don't suspend parent when async child suspend_{noirq, late} fails</title>
<updated>2016-11-26T08:56:57+00:00</updated>
<author>
<name>Brian Norris</name>
<email>briannorris@chromium.org</email>
</author>
<published>2016-11-10T01:21:08+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4cba876de64d448b458dd271f49c0e6a80a639ce'/>
<id>4cba876de64d448b458dd271f49c0e6a80a639ce</id>
<content type='text'>
commit 6f75c3fd56daf547d684127a7f83c283c3c160d1 upstream.

Consider two devices, A and B, where B is a child of A, and B utilizes
asynchronous suspend (it does not matter whether A is sync or async). If
B fails to suspend_noirq() or suspend_late(), or is interrupted by a
wakeup (pm_wakeup_pending()), then it aborts and sets the async_error
variable. However, device A does not (immediately) check the async_error
variable; it may continue to run its own suspend_noirq()/suspend_late()
callback. This is bad.

We can resolve this problem by doing our error and wakeup checking
(particularly, for the async_error flag) after waiting for children to
suspend, instead of before. This also helps align the logic for the noirq and
late suspend cases with the logic in __device_suspend().

It's easy to observe this erroneous behavior by, for example, forcing a
device to sleep a bit in its suspend_noirq() (to ensure the parent is
waiting for the child to complete), then return an error, and watch the
parent suspend_noirq() still get called. (Or similarly, fake a wakeup
event at the right (or is it wrong?) time.)

Fixes: de377b397272 (PM / sleep: Asynchronous threads for suspend_late)
Fixes: 28b6fd6e3779 (PM / sleep: Asynchronous threads for suspend_noirq)
Reported-by: Jeffy Chen &lt;jeffy.chen@rock-chips.com&gt;
Signed-off-by: Brian Norris &lt;briannorris@chromium.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6f75c3fd56daf547d684127a7f83c283c3c160d1 upstream.

Consider two devices, A and B, where B is a child of A, and B utilizes
asynchronous suspend (it does not matter whether A is sync or async). If
B fails to suspend_noirq() or suspend_late(), or is interrupted by a
wakeup (pm_wakeup_pending()), then it aborts and sets the async_error
variable. However, device A does not (immediately) check the async_error
variable; it may continue to run its own suspend_noirq()/suspend_late()
callback. This is bad.

We can resolve this problem by doing our error and wakeup checking
(particularly, for the async_error flag) after waiting for children to
suspend, instead of before. This also helps align the logic for the noirq and
late suspend cases with the logic in __device_suspend().

It's easy to observe this erroneous behavior by, for example, forcing a
device to sleep a bit in its suspend_noirq() (to ensure the parent is
waiting for the child to complete), then return an error, and watch the
parent suspend_noirq() still get called. (Or similarly, fake a wakeup
event at the right (or is it wrong?) time.)

Fixes: de377b397272 (PM / sleep: Asynchronous threads for suspend_late)
Fixes: 28b6fd6e3779 (PM / sleep: Asynchronous threads for suspend_noirq)
Reported-by: Jeffy Chen &lt;jeffy.chen@rock-chips.com&gt;
Signed-off-by: Brian Norris &lt;briannorris@chromium.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>PM / runtime: Use _rcuidle for runtime suspend tracepoints</title>
<updated>2016-09-16T00:59:58+00:00</updated>
<author>
<name>Paul E. McKenney</name>
<email>paulmck@linux.vnet.ibm.com</email>
</author>
<published>2016-04-26T17:42:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=778935778c3b88e5152a88765850009006ef2e32'/>
<id>778935778c3b88e5152a88765850009006ef2e32</id>
<content type='text'>
Further testing with false negatives suppressed by commit 293e2421fe25
("rcu: Remove superfluous versions of rcu_read_lock_sched_held()")
identified a few more unprotected uses of RCU from the idle loop.
Because RCU actively ignores idle-loop code (for energy-efficiency
reasons, among other things), using RCU from the idle loop can result
in too-short grace periods, in turn resulting in arbitrary misbehavior.

The affected function is rpm_suspend().

The resulting lockdep-RCU splat is as follows:

------------------------------------------------------------------------

Warning from omap3

===============================
[ INFO: suspicious RCU usage. ]
4.6.0-rc5-next-20160426+ #1112 Not tainted
-------------------------------
include/trace/events/rpm.h:63 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
1 lock held by swapper/0/0:
 #0:  (&amp;(&amp;dev-&gt;power.lock)-&gt;rlock){-.-...}, at: [&lt;c052ee24&gt;] __pm_runtime_suspend+0x54/0x84

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112
Hardware name: Generic OMAP36xx (Flattened Device Tree)
[&lt;c0110308&gt;] (unwind_backtrace) from [&lt;c010c3a8&gt;] (show_stack+0x10/0x14)
[&lt;c010c3a8&gt;] (show_stack) from [&lt;c047fec8&gt;] (dump_stack+0xb0/0xe4)
[&lt;c047fec8&gt;] (dump_stack) from [&lt;c052d7b4&gt;] (rpm_suspend+0x604/0x7e4)
[&lt;c052d7b4&gt;] (rpm_suspend) from [&lt;c052ee34&gt;] (__pm_runtime_suspend+0x64/0x84)
[&lt;c052ee34&gt;] (__pm_runtime_suspend) from [&lt;c04bf3bc&gt;] (omap2_gpio_prepare_for_idle+0x5c/0x70)
[&lt;c04bf3bc&gt;] (omap2_gpio_prepare_for_idle) from [&lt;c01255e8&gt;] (omap_sram_idle+0x140/0x244)
[&lt;c01255e8&gt;] (omap_sram_idle) from [&lt;c0126b48&gt;] (omap3_enter_idle_bm+0xfc/0x1ec)
[&lt;c0126b48&gt;] (omap3_enter_idle_bm) from [&lt;c0601db8&gt;] (cpuidle_enter_state+0x80/0x3d4)
[&lt;c0601db8&gt;] (cpuidle_enter_state) from [&lt;c0183c74&gt;] (cpu_startup_entry+0x198/0x3a0)
[&lt;c0183c74&gt;] (cpu_startup_entry) from [&lt;c0b00c0c&gt;] (start_kernel+0x354/0x3c8)
[&lt;c0b00c0c&gt;] (start_kernel) from [&lt;8000807c&gt;] (0x8000807c)

------------------------------------------------------------------------

Reported-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Further testing with false negatives suppressed by commit 293e2421fe25
("rcu: Remove superfluous versions of rcu_read_lock_sched_held()")
identified a few more unprotected uses of RCU from the idle loop.
Because RCU actively ignores idle-loop code (for energy-efficiency
reasons, among other things), using RCU from the idle loop can result
in too-short grace periods, in turn resulting in arbitrary misbehavior.

The affected function is rpm_suspend().

The resulting lockdep-RCU splat is as follows:

------------------------------------------------------------------------

Warning from omap3

===============================
[ INFO: suspicious RCU usage. ]
4.6.0-rc5-next-20160426+ #1112 Not tainted
-------------------------------
include/trace/events/rpm.h:63 suspicious rcu_dereference_check() usage!

other info that might help us debug this:

RCU used illegally from idle CPU!
rcu_scheduler_active = 1, debug_locks = 0
RCU used illegally from extended quiescent state!
1 lock held by swapper/0/0:
 #0:  (&amp;(&amp;dev-&gt;power.lock)-&gt;rlock){-.-...}, at: [&lt;c052ee24&gt;] __pm_runtime_suspend+0x54/0x84

stack backtrace:
CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1112
Hardware name: Generic OMAP36xx (Flattened Device Tree)
[&lt;c0110308&gt;] (unwind_backtrace) from [&lt;c010c3a8&gt;] (show_stack+0x10/0x14)
[&lt;c010c3a8&gt;] (show_stack) from [&lt;c047fec8&gt;] (dump_stack+0xb0/0xe4)
[&lt;c047fec8&gt;] (dump_stack) from [&lt;c052d7b4&gt;] (rpm_suspend+0x604/0x7e4)
[&lt;c052d7b4&gt;] (rpm_suspend) from [&lt;c052ee34&gt;] (__pm_runtime_suspend+0x64/0x84)
[&lt;c052ee34&gt;] (__pm_runtime_suspend) from [&lt;c04bf3bc&gt;] (omap2_gpio_prepare_for_idle+0x5c/0x70)
[&lt;c04bf3bc&gt;] (omap2_gpio_prepare_for_idle) from [&lt;c01255e8&gt;] (omap_sram_idle+0x140/0x244)
[&lt;c01255e8&gt;] (omap_sram_idle) from [&lt;c0126b48&gt;] (omap3_enter_idle_bm+0xfc/0x1ec)
[&lt;c0126b48&gt;] (omap3_enter_idle_bm) from [&lt;c0601db8&gt;] (cpuidle_enter_state+0x80/0x3d4)
[&lt;c0601db8&gt;] (cpuidle_enter_state) from [&lt;c0183c74&gt;] (cpu_startup_entry+0x198/0x3a0)
[&lt;c0183c74&gt;] (cpu_startup_entry) from [&lt;c0b00c0c&gt;] (start_kernel+0x354/0x3c8)
[&lt;c0b00c0c&gt;] (start_kernel) from [&lt;8000807c&gt;] (0x8000807c)

------------------------------------------------------------------------

Reported-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM / runtime: Add _rcuidle suffix to allow rpm_idle() use from idle</title>
<updated>2016-08-31T01:00:59+00:00</updated>
<author>
<name>Paul E. McKenney</name>
<email>paulmck@linux.vnet.ibm.com</email>
</author>
<published>2016-04-26T20:03:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d7737ce964d944dd07e25b0f569edcd550ede18c'/>
<id>d7737ce964d944dd07e25b0f569edcd550ede18c</id>
<content type='text'>
This commit appends a few _rcuidle suffixes to fix the following
RCU-used-from-idle bug:

&gt; ===============================
&gt; [ INFO: suspicious RCU usage. ]
&gt; 4.6.0-rc5-next-20160426+ #1116 Not tainted
&gt; -------------------------------
&gt; include/trace/events/rpm.h:95 suspicious rcu_dereference_check() usage!
&gt;
&gt; other info that might help us debug this:
&gt;
&gt;
&gt; RCU used illegally from idle CPU!
&gt; rcu_scheduler_active = 1, debug_locks = 0
&gt; RCU used illegally from extended quiescent state!
&gt; 1 lock held by swapper/0/0:
&gt;  #0:  (&amp;(&amp;dev-&gt;power.lock)-&gt;rlock){-.-...}, at: [&lt;c052cc2c&gt;] __rpm_callback+0x58/0x60
&gt;
&gt; stack backtrace:
&gt; CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116
&gt; Hardware name: Generic OMAP36xx (Flattened Device Tree)
&gt; [&lt;c0110290&gt;] (unwind_backtrace) from [&lt;c010c3a8&gt;] (show_stack+0x10/0x14)
&gt; [&lt;c010c3a8&gt;] (show_stack) from [&lt;c047fd68&gt;] (dump_stack+0xb0/0xe4)
&gt; [&lt;c047fd68&gt;] (dump_stack) from [&lt;c052d5d0&gt;] (rpm_suspend+0x580/0x768)
&gt; [&lt;c052d5d0&gt;] (rpm_suspend) from [&lt;c052ec58&gt;] (__pm_runtime_suspend+0x64/0x84)
&gt; [&lt;c052ec58&gt;] (__pm_runtime_suspend) from [&lt;c04bf25c&gt;] (omap2_gpio_prepare_for_idle+0x5c/0x70)
&gt; [&lt;c04bf25c&gt;] (omap2_gpio_prepare_for_idle) from [&lt;c0125568&gt;] (omap_sram_idle+0x140/0x244)
&gt; [&lt;c0125568&gt;] (omap_sram_idle) from [&lt;c01269dc&gt;] (omap3_enter_idle_bm+0xfc/0x1ec)
&gt; [&lt;c01269dc&gt;] (omap3_enter_idle_bm) from [&lt;c0601bdc&gt;] (cpuidle_enter_state+0x80/0x3d4)
&gt; [&lt;c0601bdc&gt;] (cpuidle_enter_state) from [&lt;c0183b08&gt;] (cpu_startup_entry+0x198/0x3a0)
&gt; [&lt;c0183b08&gt;] (cpu_startup_entry) from [&lt;c0b00c0c&gt;] (start_kernel+0x354/0x3c8)
&gt; [&lt;c0b00c0c&gt;] (start_kernel) from [&lt;8000807c&gt;] (0x8000807c)

In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!"

Reported-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
WhACKED-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This commit appends a few _rcuidle suffixes to fix the following
RCU-used-from-idle bug:

&gt; ===============================
&gt; [ INFO: suspicious RCU usage. ]
&gt; 4.6.0-rc5-next-20160426+ #1116 Not tainted
&gt; -------------------------------
&gt; include/trace/events/rpm.h:95 suspicious rcu_dereference_check() usage!
&gt;
&gt; other info that might help us debug this:
&gt;
&gt;
&gt; RCU used illegally from idle CPU!
&gt; rcu_scheduler_active = 1, debug_locks = 0
&gt; RCU used illegally from extended quiescent state!
&gt; 1 lock held by swapper/0/0:
&gt;  #0:  (&amp;(&amp;dev-&gt;power.lock)-&gt;rlock){-.-...}, at: [&lt;c052cc2c&gt;] __rpm_callback+0x58/0x60
&gt;
&gt; stack backtrace:
&gt; CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1116
&gt; Hardware name: Generic OMAP36xx (Flattened Device Tree)
&gt; [&lt;c0110290&gt;] (unwind_backtrace) from [&lt;c010c3a8&gt;] (show_stack+0x10/0x14)
&gt; [&lt;c010c3a8&gt;] (show_stack) from [&lt;c047fd68&gt;] (dump_stack+0xb0/0xe4)
&gt; [&lt;c047fd68&gt;] (dump_stack) from [&lt;c052d5d0&gt;] (rpm_suspend+0x580/0x768)
&gt; [&lt;c052d5d0&gt;] (rpm_suspend) from [&lt;c052ec58&gt;] (__pm_runtime_suspend+0x64/0x84)
&gt; [&lt;c052ec58&gt;] (__pm_runtime_suspend) from [&lt;c04bf25c&gt;] (omap2_gpio_prepare_for_idle+0x5c/0x70)
&gt; [&lt;c04bf25c&gt;] (omap2_gpio_prepare_for_idle) from [&lt;c0125568&gt;] (omap_sram_idle+0x140/0x244)
&gt; [&lt;c0125568&gt;] (omap_sram_idle) from [&lt;c01269dc&gt;] (omap3_enter_idle_bm+0xfc/0x1ec)
&gt; [&lt;c01269dc&gt;] (omap3_enter_idle_bm) from [&lt;c0601bdc&gt;] (cpuidle_enter_state+0x80/0x3d4)
&gt; [&lt;c0601bdc&gt;] (cpuidle_enter_state) from [&lt;c0183b08&gt;] (cpu_startup_entry+0x198/0x3a0)
&gt; [&lt;c0183b08&gt;] (cpu_startup_entry) from [&lt;c0b00c0c&gt;] (start_kernel+0x354/0x3c8)
&gt; [&lt;c0b00c0c&gt;] (start_kernel) from [&lt;8000807c&gt;] (0x8000807c)

In the immortal words of Steven Rostedt, "*Whack* *Whack* *Whack*!!!"

Reported-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
WhACKED-by: Steven Rostedt &lt;rostedt@goodmis.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM / runtime: Add _rcuidle suffix to allow rpm_resume() to be called from idle</title>
<updated>2016-08-31T00:59:20+00:00</updated>
<author>
<name>Paul E. McKenney</name>
<email>paulmck@linux.vnet.ibm.com</email>
</author>
<published>2016-04-26T20:38:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d44c950e9398e639e124014e5872480a37b67259'/>
<id>d44c950e9398e639e124014e5872480a37b67259</id>
<content type='text'>
This commit applies another _rcuidle suffix to fix an RCU use from
idle.

&gt; ===============================
&gt; [ INFO: suspicious RCU usage. ]
&gt; 4.6.0-rc5-next-20160426+ #1122 Not tainted
&gt; -------------------------------
&gt; include/trace/events/rpm.h:69 suspicious rcu_dereference_check() usage!
&gt;
&gt; other info that might help us debug this:
&gt;
&gt;
&gt; RCU used illegally from idle CPU!
&gt; rcu_scheduler_active = 1, debug_locks = 0
&gt; RCU used illegally from extended quiescent state!
&gt; 1 lock held by swapper/0/0:
&gt;  #0:  (&amp;(&amp;dev-&gt;power.lock)-&gt;rlock){-.-...}, at: [&lt;c052e3dc&gt;] __pm_runtime_resume+0x3c/0x64
&gt;
&gt; stack backtrace:
&gt; CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1122
&gt; Hardware name: Generic OMAP36xx (Flattened Device Tree)
&gt; [&lt;c0110290&gt;] (unwind_backtrace) from [&lt;c010c3a8&gt;] (show_stack+0x10/0x14)
&gt; [&lt;c010c3a8&gt;] (show_stack) from [&lt;c047fd68&gt;] (dump_stack+0xb0/0xe4)
&gt; [&lt;c047fd68&gt;] (dump_stack) from [&lt;c052e178&gt;] (rpm_resume+0x5cc/0x7f4)
&gt; [&lt;c052e178&gt;] (rpm_resume) from [&lt;c052e3ec&gt;] (__pm_runtime_resume+0x4c/0x64)
&gt; [&lt;c052e3ec&gt;] (__pm_runtime_resume) from [&lt;c04bf2c4&gt;] (omap2_gpio_resume_after_idle+0x54/0x68)
&gt; [&lt;c04bf2c4&gt;] (omap2_gpio_resume_after_idle) from [&lt;c01269dc&gt;] (omap3_enter_idle_bm+0xfc/0x1ec)
&gt; [&lt;c01269dc&gt;] (omap3_enter_idle_bm) from [&lt;c060198c&gt;] (cpuidle_enter_state+0x80/0x3d4)
&gt; [&lt;c060198c&gt;] (cpuidle_enter_state) from [&lt;c0183b08&gt;] (cpu_startup_entry+0x198/0x3a0)
&gt; [&lt;c0183b08&gt;] (cpu_startup_entry) from [&lt;c0b00c0c&gt;] (start_kernel+0x354/0x3c8)
&gt; [&lt;c0b00c0c&gt;] (start_kernel) from [&lt;8000807c&gt;] (0x8000807c)

Reported-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This commit applies another _rcuidle suffix to fix an RCU use from
idle.

&gt; ===============================
&gt; [ INFO: suspicious RCU usage. ]
&gt; 4.6.0-rc5-next-20160426+ #1122 Not tainted
&gt; -------------------------------
&gt; include/trace/events/rpm.h:69 suspicious rcu_dereference_check() usage!
&gt;
&gt; other info that might help us debug this:
&gt;
&gt;
&gt; RCU used illegally from idle CPU!
&gt; rcu_scheduler_active = 1, debug_locks = 0
&gt; RCU used illegally from extended quiescent state!
&gt; 1 lock held by swapper/0/0:
&gt;  #0:  (&amp;(&amp;dev-&gt;power.lock)-&gt;rlock){-.-...}, at: [&lt;c052e3dc&gt;] __pm_runtime_resume+0x3c/0x64
&gt;
&gt; stack backtrace:
&gt; CPU: 0 PID: 0 Comm: swapper/0 Not tainted 4.6.0-rc5-next-20160426+ #1122
&gt; Hardware name: Generic OMAP36xx (Flattened Device Tree)
&gt; [&lt;c0110290&gt;] (unwind_backtrace) from [&lt;c010c3a8&gt;] (show_stack+0x10/0x14)
&gt; [&lt;c010c3a8&gt;] (show_stack) from [&lt;c047fd68&gt;] (dump_stack+0xb0/0xe4)
&gt; [&lt;c047fd68&gt;] (dump_stack) from [&lt;c052e178&gt;] (rpm_resume+0x5cc/0x7f4)
&gt; [&lt;c052e178&gt;] (rpm_resume) from [&lt;c052e3ec&gt;] (__pm_runtime_resume+0x4c/0x64)
&gt; [&lt;c052e3ec&gt;] (__pm_runtime_resume) from [&lt;c04bf2c4&gt;] (omap2_gpio_resume_after_idle+0x54/0x68)
&gt; [&lt;c04bf2c4&gt;] (omap2_gpio_resume_after_idle) from [&lt;c01269dc&gt;] (omap3_enter_idle_bm+0xfc/0x1ec)
&gt; [&lt;c01269dc&gt;] (omap3_enter_idle_bm) from [&lt;c060198c&gt;] (cpuidle_enter_state+0x80/0x3d4)
&gt; [&lt;c060198c&gt;] (cpuidle_enter_state) from [&lt;c0183b08&gt;] (cpu_startup_entry+0x198/0x3a0)
&gt; [&lt;c0183b08&gt;] (cpu_startup_entry) from [&lt;c0b00c0c&gt;] (start_kernel+0x354/0x3c8)
&gt; [&lt;c0b00c0c&gt;] (start_kernel) from [&lt;8000807c&gt;] (0x8000807c)

Reported-by: Tony Lindgren &lt;tony@atomide.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Tested-by: Tony Lindgren &lt;tony@atomide.com&gt;
Tested-by: Guenter Roeck &lt;linux@roeck-us.net&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'pm-extra-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm</title>
<updated>2016-08-06T03:26:16+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-08-06T03:26:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=11d8ec408d0aa2dae7ca89f95e497b8f22427b20'/>
<id>11d8ec408d0aa2dae7ca89f95e497b8f22427b20</id>
<content type='text'>
Pull more power management updates from Rafael Wysocki:
 "A few more fixes and cleanups in the x86-64 low-level hibernation
  code, PM core, cpufreq (Kconfig and intel_pstate), and the operating
  points framework.

  Specifics:

   - Prevent the low-level assembly hibernate code on x86-64 from
     referring to __PAGE_OFFSET directly as a symbol which doesn't work
     when the kernel identity mapping base is randomized, in which case
     __PAGE_OFFSET is a variable (Rafael Wysocki).

   - Avoid selecting CPU_FREQ_STAT by default as the statistics are not
     required for proper cpufreq operation (Borislav Petkov).

   - Add Skylake-X and Broadwell-X IDs to the intel_pstate's list of
     processors where out-of-band (OBB) control of P-states is possible
     and if that is in use, intel_pstate should not attempt to manage
     P-states (Srinivas Pandruvada).

   - Drop some unnecessary checks from the wakeup IRQ handling code in
     the PM core (Markus Elfring).

   - Reduce the number operating performance point (OPP) lookups in one
     of the OPP framework's helper functions (Jisheng Zhang)"

* tag 'pm-extra-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  x86/power/64: Do not refer to __PAGE_OFFSET from assembly code
  cpufreq: Do not default-yes CPU_FREQ_STAT
  cpufreq: intel_pstate: Add more out-of-band IDs
  PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
  PM-wakeup: Delete unnecessary checks before three function calls
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull more power management updates from Rafael Wysocki:
 "A few more fixes and cleanups in the x86-64 low-level hibernation
  code, PM core, cpufreq (Kconfig and intel_pstate), and the operating
  points framework.

  Specifics:

   - Prevent the low-level assembly hibernate code on x86-64 from
     referring to __PAGE_OFFSET directly as a symbol which doesn't work
     when the kernel identity mapping base is randomized, in which case
     __PAGE_OFFSET is a variable (Rafael Wysocki).

   - Avoid selecting CPU_FREQ_STAT by default as the statistics are not
     required for proper cpufreq operation (Borislav Petkov).

   - Add Skylake-X and Broadwell-X IDs to the intel_pstate's list of
     processors where out-of-band (OBB) control of P-states is possible
     and if that is in use, intel_pstate should not attempt to manage
     P-states (Srinivas Pandruvada).

   - Drop some unnecessary checks from the wakeup IRQ handling code in
     the PM core (Markus Elfring).

   - Reduce the number operating performance point (OPP) lookups in one
     of the OPP framework's helper functions (Jisheng Zhang)"

* tag 'pm-extra-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
  x86/power/64: Do not refer to __PAGE_OFFSET from assembly code
  cpufreq: Do not default-yes CPU_FREQ_STAT
  cpufreq: intel_pstate: Add more out-of-band IDs
  PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
  PM-wakeup: Delete unnecessary checks before three function calls
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux</title>
<updated>2016-08-05T13:48:22+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2016-08-05T13:48:22+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=6c84239d595dc6ffe39f0f03dae2f64ed200db95'/>
<id>6c84239d595dc6ffe39f0f03dae2f64ed200db95</id>
<content type='text'>
Pull RTC updates from Alexandre Belloni:
 "RTC for 4.8

  Cleanups:
   - huge cleanup of rtc-generic and char/genrtc this allowed to cleanup
     rtc-cmos, rtc-sh, rtc-m68k, rtc-powerpc and rtc-parisc
   - move mn10300 to rtc-cmos

  Subsystem:
   - fix wakealarms after hibernate
   - multiples fixes for rctest
   - simplify implementations of .read_alarm

  New drivers:
   - Maxim MAX6916

  Drivers:
   - ds1307: fix weekday
   - m41t80: add wakeup support
   - pcf85063: add support for PCF85063A variant
   - rv8803: extend i2c fix and other fixes
   - s35390a: fix alarm reading, this fixes instant reboot after
     shutdown for QNAP TS-41x
   - s3c: clock fixes"

* tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (65 commits)
  rtc: rv8803: Clear V1F when setting the time
  rtc: rv8803: Stop the clock while setting the time
  rtc: rv8803: Always apply the I²C workaround
  rtc: rv8803: Fix read day of week
  rtc: rv8803: Remove the check for valid time
  rtc: rv8803: Kconfig: Indicate rx8900 support
  rtc: asm9260: remove .owner field for driver
  rtc: at91sam9: Fix missing spin_lock_init()
  rtc: m41t80: add suspend handlers for alarm IRQ
  rtc: m41t80: make it a real error message
  rtc: pcf85063: Add support for the PCF85063A device
  rtc: pcf85063: fix year range
  rtc: hym8563: in .read_alarm set .tm_sec to 0 to signal minute accuracy
  rtc: explicitly set tm_sec = 0 for drivers with minute accurancy
  rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
  rtc: s3c: Remove unnecessary call to disable already disabled clock
  rtc: abx80x: use devm_add_action_or_reset()
  rtc: m41t80: use devm_add_action_or_reset()
  rtc: fix a typo and reduce three empty lines to one
  rtc: s35390a: improve two comments in .set_alarm
  ...
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Pull RTC updates from Alexandre Belloni:
 "RTC for 4.8

  Cleanups:
   - huge cleanup of rtc-generic and char/genrtc this allowed to cleanup
     rtc-cmos, rtc-sh, rtc-m68k, rtc-powerpc and rtc-parisc
   - move mn10300 to rtc-cmos

  Subsystem:
   - fix wakealarms after hibernate
   - multiples fixes for rctest
   - simplify implementations of .read_alarm

  New drivers:
   - Maxim MAX6916

  Drivers:
   - ds1307: fix weekday
   - m41t80: add wakeup support
   - pcf85063: add support for PCF85063A variant
   - rv8803: extend i2c fix and other fixes
   - s35390a: fix alarm reading, this fixes instant reboot after
     shutdown for QNAP TS-41x
   - s3c: clock fixes"

* tag 'rtc-4.8' of git://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux: (65 commits)
  rtc: rv8803: Clear V1F when setting the time
  rtc: rv8803: Stop the clock while setting the time
  rtc: rv8803: Always apply the I²C workaround
  rtc: rv8803: Fix read day of week
  rtc: rv8803: Remove the check for valid time
  rtc: rv8803: Kconfig: Indicate rx8900 support
  rtc: asm9260: remove .owner field for driver
  rtc: at91sam9: Fix missing spin_lock_init()
  rtc: m41t80: add suspend handlers for alarm IRQ
  rtc: m41t80: make it a real error message
  rtc: pcf85063: Add support for the PCF85063A device
  rtc: pcf85063: fix year range
  rtc: hym8563: in .read_alarm set .tm_sec to 0 to signal minute accuracy
  rtc: explicitly set tm_sec = 0 for drivers with minute accurancy
  rtc: s3c: Add s3c_rtc_{enable/disable}_clk in s3c_rtc_setfreq()
  rtc: s3c: Remove unnecessary call to disable already disabled clock
  rtc: abx80x: use devm_add_action_or_reset()
  rtc: m41t80: use devm_add_action_or_reset()
  rtc: fix a typo and reduce three empty lines to one
  rtc: s35390a: improve two comments in .set_alarm
  ...
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge branches 'pm-sleep', 'pm-cpufreq', 'pm-core' and 'pm-opp'</title>
<updated>2016-08-05T13:46:55+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2016-08-05T13:46:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e2b3b80de5cda284c885721e873f9a6e90f68ef8'/>
<id>e2b3b80de5cda284c885721e873f9a6e90f68ef8</id>
<content type='text'>
* pm-sleep:
  x86/power/64: Do not refer to __PAGE_OFFSET from assembly code

* pm-cpufreq:
  cpufreq: Do not default-yes CPU_FREQ_STAT
  cpufreq: intel_pstate: Add more out-of-band IDs

* pm-core:
  PM-wakeup: Delete unnecessary checks before three function calls

* pm-opp:
  PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
* pm-sleep:
  x86/power/64: Do not refer to __PAGE_OFFSET from assembly code

* pm-cpufreq:
  cpufreq: Do not default-yes CPU_FREQ_STAT
  cpufreq: intel_pstate: Add more out-of-band IDs

* pm-core:
  PM-wakeup: Delete unnecessary checks before three function calls

* pm-opp:
  PM / OPP: optimize dev_pm_opp_set_rate() performance a bit
</pre>
</div>
</content>
</entry>
<entry>
<title>PM / OPP: optimize dev_pm_opp_set_rate() performance a bit</title>
<updated>2016-07-28T21:54:16+00:00</updated>
<author>
<name>Jisheng Zhang</name>
<email>jszhang@marvell.com</email>
</author>
<published>2016-07-25T06:11:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=067b7ce083df6c69e67345bdba658ab59274cc01'/>
<id>067b7ce083df6c69e67345bdba658ab59274cc01</id>
<content type='text'>
In dev_pm_opp_set_rate(), _find_opp_table() is called 4 times: once by
_get_opp_clk(), once by dev_pm_opp_set_rate() itself, and twice by
dev_pm_opp_find_freq_ceil(). If there are several opp_tables in the
system, three times of opp table finding is a big waste. This patch
reduced the call of _find_opp_table() to twice.

Signed-off-by: Jisheng Zhang &lt;jszhang@marvell.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
In dev_pm_opp_set_rate(), _find_opp_table() is called 4 times: once by
_get_opp_clk(), once by dev_pm_opp_set_rate() itself, and twice by
dev_pm_opp_find_freq_ceil(). If there are several opp_tables in the
system, three times of opp table finding is a big waste. This patch
reduced the call of _find_opp_table() to twice.

Signed-off-by: Jisheng Zhang &lt;jszhang@marvell.com&gt;
Acked-by: Viresh Kumar &lt;viresh.kumar@linaro.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>PM-wakeup: Delete unnecessary checks before three function calls</title>
<updated>2016-07-28T21:51:04+00:00</updated>
<author>
<name>Markus Elfring</name>
<email>elfring@users.sourceforge.net</email>
</author>
<published>2016-07-23T15:04:00+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=4f48ec8a1c070f00c3d675b664e8b3879e5286e5'/>
<id>4f48ec8a1c070f00c3d675b664e8b3879e5286e5</id>
<content type='text'>
The following functions test whether their argument is NULL
and then return immediately.
 * dev_pm_arm_wake_irq
 * dev_pm_disarm_wake_irq
 * wakeup_source_unregister

Thus the test around the calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring &lt;elfring@users.sourceforge.net&gt;
Acked-by: Pavel Machek &lt;pavel@ucw.cz&gt;
[ rjw: Minor whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The following functions test whether their argument is NULL
and then return immediately.
 * dev_pm_arm_wake_irq
 * dev_pm_disarm_wake_irq
 * wakeup_source_unregister

Thus the test around the calls is not needed.

This issue was detected by using the Coccinelle software.

Signed-off-by: Markus Elfring &lt;elfring@users.sourceforge.net&gt;
Acked-by: Pavel Machek &lt;pavel@ucw.cz&gt;
[ rjw: Minor whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
