<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/regulator, branch v5.4.78</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>regulator: defer probe when trying to get voltage from unresolved supply</title>
<updated>2020-11-10T11:37:28+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-11-02T21:27:27+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f352cca84625b49c170dba841b60791dee737357'/>
<id>f352cca84625b49c170dba841b60791dee737357</id>
<content type='text'>
commit cf1ad559a20d1930aa7b47a52f54e1f8718de301 upstream.

regulator_get_voltage_rdev() is called in regulator probe() when
applying machine constraints.  The "fixed" commit exposed the problem
that non-bypassed regulators can forward the request to its parent
(like bypassed ones) supply. Return -EPROBE_DEFER when the supply
is expected but not resolved yet.

Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reported-by: Ondřej Jirman &lt;megous@megous.com&gt;
Reported-by: Corentin Labbe &lt;clabbe.montjoie@gmail.com&gt;
Tested-by: Ondřej Jirman &lt;megous@megous.com&gt;
Link: https://lore.kernel.org/r/a9041d68b4d35e4a2dd71629c8a6422662acb5ee.1604351936.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&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 cf1ad559a20d1930aa7b47a52f54e1f8718de301 upstream.

regulator_get_voltage_rdev() is called in regulator probe() when
applying machine constraints.  The "fixed" commit exposed the problem
that non-bypassed regulators can forward the request to its parent
(like bypassed ones) supply. Return -EPROBE_DEFER when the supply
is expected but not resolved yet.

Fixes: aea6cb99703e ("regulator: resolve supply after creating regulator")
Cc: stable@vger.kernel.org
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reported-by: Ondřej Jirman &lt;megous@megous.com&gt;
Reported-by: Corentin Labbe &lt;clabbe.montjoie@gmail.com&gt;
Tested-by: Ondřej Jirman &lt;megous@megous.com&gt;
Link: https://lore.kernel.org/r/a9041d68b4d35e4a2dd71629c8a6422662acb5ee.1604351936.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: resolve supply after creating regulator</title>
<updated>2020-10-29T08:57:34+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-09-26T21:32:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0120ec32a7774b5061ced1a9a7ff833edd8b4cb6'/>
<id>0120ec32a7774b5061ced1a9a7ff833edd8b4cb6</id>
<content type='text'>
[ Upstream commit aea6cb99703e17019e025aa71643b4d3e0a24413 ]

When creating a new regulator its supply cannot create the sysfs link
because the device is not yet published. Remove early supply resolving
since it will be done later anyway. This makes the following error
disappear and the symlinks get created instead.

  DCDC_REG1: supplied by VSYS
  VSYS: could not add device link regulator.3 err -2

Note: It doesn't fix the problem for bypassed regulators, though.

Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Link: https://lore.kernel.org/r/ba09e0a8617ffeeb25cb4affffe6f3149319cef8.1601155770.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit aea6cb99703e17019e025aa71643b4d3e0a24413 ]

When creating a new regulator its supply cannot create the sysfs link
because the device is not yet published. Remove early supply resolving
since it will be done later anyway. This makes the following error
disappear and the symlinks get created instead.

  DCDC_REG1: supplied by VSYS
  VSYS: could not add device link regulator.3 err -2

Note: It doesn't fix the problem for bypassed regulators, though.

Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Link: https://lore.kernel.org/r/ba09e0a8617ffeeb25cb4affffe6f3149319cef8.1601155770.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: axp20x: fix LDO2/4 description</title>
<updated>2020-10-01T11:18:21+00:00</updated>
<author>
<name>Icenowy Zheng</name>
<email>icenowy@aosc.io</email>
</author>
<published>2020-09-23T00:51:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=87f7a4910e57cde3a223fe1bf5296699cce64445'/>
<id>87f7a4910e57cde3a223fe1bf5296699cce64445</id>
<content type='text'>
[ Upstream commit fbb5a79d2fe7b01c6424fbbc04368373b1672d61 ]

Currently we wrongly set the mask of value of LDO2/4 both to the mask of
LDO2, and the LDO4 voltage configuration is left untouched. This leads
to conflict when LDO2/4 are both in use.

Fix this issue by setting different vsel_mask to both regulators.

Fixes: db4a555f7c4c ("regulator: axp20x: use defines for masks")
Signed-off-by: Icenowy Zheng &lt;icenowy@aosc.io&gt;
Link: https://lore.kernel.org/r/20200923005142.147135-1-icenowy@aosc.io
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit fbb5a79d2fe7b01c6424fbbc04368373b1672d61 ]

Currently we wrongly set the mask of value of LDO2/4 both to the mask of
LDO2, and the LDO4 voltage configuration is left untouched. This leads
to conflict when LDO2/4 are both in use.

Fix this issue by setting different vsel_mask to both regulators.

Fixes: db4a555f7c4c ("regulator: axp20x: use defines for masks")
Signed-off-by: Icenowy Zheng &lt;icenowy@aosc.io&gt;
Link: https://lore.kernel.org/r/20200923005142.147135-1-icenowy@aosc.io
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: pwm: Fix machine constraints application</title>
<updated>2020-09-23T10:40:35+00:00</updated>
<author>
<name>Vincent Whitchurch</name>
<email>vincent.whitchurch@axis.com</email>
</author>
<published>2020-09-02T13:09:52+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=8aeb6173e87f0c02b6f2c670ba424287705c5e0f'/>
<id>8aeb6173e87f0c02b6f2c670ba424287705c5e0f</id>
<content type='text'>
[ Upstream commit 59ae97a7a9e1499c2070e29841d1c4be4ae2994a ]

If the zero duty cycle doesn't correspond to any voltage in the voltage
table, the PWM regulator returns an -EINVAL from get_voltage_sel() which
results in the core erroring out with a "failed to get the current
voltage" and ending up not applying the machine constraints.

Instead, return -ENOTRECOVERABLE which makes the core set the voltage
since it's at an unknown value.

For example, with this device tree:

	fooregulator {
		compatible = "pwm-regulator";
		pwms = &lt;&amp;foopwm 0 100000&gt;;
		regulator-min-microvolt = &lt;2250000&gt;;
		regulator-max-microvolt = &lt;2250000&gt;;
		regulator-name = "fooregulator";
		regulator-always-on;
		regulator-boot-on;
		voltage-table = &lt;2250000 30&gt;;
	};

Before this patch:

  fooregulator: failed to get the current voltage(-22)

After this patch:

  fooregulator: Setting 2250000-2250000uV
  fooregulator: 2250 mV

Signed-off-by: Vincent Whitchurch &lt;vincent.whitchurch@axis.com&gt;
Link: https://lore.kernel.org/r/20200902130952.24880-1-vincent.whitchurch@axis.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 59ae97a7a9e1499c2070e29841d1c4be4ae2994a ]

If the zero duty cycle doesn't correspond to any voltage in the voltage
table, the PWM regulator returns an -EINVAL from get_voltage_sel() which
results in the core erroring out with a "failed to get the current
voltage" and ending up not applying the machine constraints.

Instead, return -ENOTRECOVERABLE which makes the core set the voltage
since it's at an unknown value.

For example, with this device tree:

	fooregulator {
		compatible = "pwm-regulator";
		pwms = &lt;&amp;foopwm 0 100000&gt;;
		regulator-min-microvolt = &lt;2250000&gt;;
		regulator-max-microvolt = &lt;2250000&gt;;
		regulator-name = "fooregulator";
		regulator-always-on;
		regulator-boot-on;
		voltage-table = &lt;2250000 30&gt;;
	};

Before this patch:

  fooregulator: failed to get the current voltage(-22)

After this patch:

  fooregulator: Setting 2250000-2250000uV
  fooregulator: 2250 mV

Signed-off-by: Vincent Whitchurch &lt;vincent.whitchurch@axis.com&gt;
Link: https://lore.kernel.org/r/20200902130952.24880-1-vincent.whitchurch@axis.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: core: Fix slab-out-of-bounds in regulator_unlock_recursive()</title>
<updated>2020-09-17T11:47:52+00:00</updated>
<author>
<name>Dmitry Osipenko</name>
<email>digetx@gmail.com</email>
</author>
<published>2020-08-31T20:43:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=a467624aef02df2a8d7d6dc7b0b3625c8133b6b0'/>
<id>a467624aef02df2a8d7d6dc7b0b3625c8133b6b0</id>
<content type='text'>
commit 0a7416f94707c60b9f66b01c0a505b7e41375f3a upstream.

The recent commit 7d8196641ee1 ("regulator: Remove pointer table
overallocation") changed the size of coupled_rdevs and now KASAN is able
to detect slab-out-of-bounds problem in regulator_unlock_recursive(),
which is a legit problem caused by a typo in the code. The recursive
unlock function uses n_coupled value of a parent regulator for unlocking
supply regulator, while supply's n_coupled should be used. In practice
problem may only affect platforms that use coupled regulators.

Cc: stable@vger.kernel.org # 5.0+
Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Link: https://lore.kernel.org/r/20200831204335.19489-1-digetx@gmail.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&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 0a7416f94707c60b9f66b01c0a505b7e41375f3a upstream.

The recent commit 7d8196641ee1 ("regulator: Remove pointer table
overallocation") changed the size of coupled_rdevs and now KASAN is able
to detect slab-out-of-bounds problem in regulator_unlock_recursive(),
which is a legit problem caused by a typo in the code. The recursive
unlock function uses n_coupled value of a parent regulator for unlocking
supply regulator, while supply's n_coupled should be used. In practice
problem may only affect platforms that use coupled regulators.

Cc: stable@vger.kernel.org # 5.0+
Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Link: https://lore.kernel.org/r/20200831204335.19489-1-digetx@gmail.com
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: plug of_node leak in regulator_register()'s error path</title>
<updated>2020-09-17T11:47:52+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-08-12T01:31:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=dfbb9cea5a4b07f6a5445d2f821041aae50b7632'/>
<id>dfbb9cea5a4b07f6a5445d2f821041aae50b7632</id>
<content type='text'>
commit d3c731564e09b6c2ebefcd1344743a91a237d6dc upstream.

By calling device_initialize() earlier and noting that kfree(NULL) is
ok, we can save a bit of code in error handling and plug of_node leak.
Fixed commit already did part of the work.

Fixes: 9177514ce349 ("regulator: fix memory leak on error path of regulator_register()")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reviewed-by: Vladimir Zapolskiy &lt;vz@mleia.com&gt;
Acked-by: Vladimir Zapolskiy &lt;vz@mleia.com&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/f5035b1b4d40745e66bacd571bbbb5e4644d21a1.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&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 d3c731564e09b6c2ebefcd1344743a91a237d6dc upstream.

By calling device_initialize() earlier and noting that kfree(NULL) is
ok, we can save a bit of code in error handling and plug of_node leak.
Fixed commit already did part of the work.

Fixes: 9177514ce349 ("regulator: fix memory leak on error path of regulator_register()")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reviewed-by: Vladimir Zapolskiy &lt;vz@mleia.com&gt;
Acked-by: Vladimir Zapolskiy &lt;vz@mleia.com&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/f5035b1b4d40745e66bacd571bbbb5e4644d21a1.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: push allocation in set_consumer_device_supply() out of lock</title>
<updated>2020-09-17T11:47:52+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-08-12T01:31:36+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=047a71ff5e9d96ec23cfa1b4cab67e512e0edc37'/>
<id>047a71ff5e9d96ec23cfa1b4cab67e512e0edc37</id>
<content type='text'>
commit 5c06540165d443c6455123eb48e7f1a9b618ab34 upstream.

Pull regulator_list_mutex into set_consumer_device_supply() and keep
allocations outside of it. Fourth of the fs_reclaim deadlock case.

Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/f0380bdb3d60aeefa9693c4e234d2dcda7e56747.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&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 5c06540165d443c6455123eb48e7f1a9b618ab34 upstream.

Pull regulator_list_mutex into set_consumer_device_supply() and keep
allocations outside of it. Fourth of the fs_reclaim deadlock case.

Fixes: 45389c47526d ("regulator: core: Add early supply resolution for regulators")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/f0380bdb3d60aeefa9693c4e234d2dcda7e56747.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: push allocations in create_regulator() outside of lock</title>
<updated>2020-09-17T11:47:52+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-08-12T01:31:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=31d89652c38443f27e386b78a4eb46aed0ccd1c7'/>
<id>31d89652c38443f27e386b78a4eb46aed0ccd1c7</id>
<content type='text'>
commit 87fe29b61f9522a3d7b60a4580851f548558186f upstream.

Move all allocations outside of the regulator_lock()ed section.

======================================================
WARNING: possible circular locking dependency detected
5.7.13+ #535 Not tainted
------------------------------------------------------
f2fs_discard-179:7/702 is trying to acquire lock:
c0e5d920 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x2c0

but task is already holding lock:
cb95b080 (&amp;dcc-&gt;cmd_lock){+.+.}-{3:3}, at: __issue_discard_cmd+0xec/0x5f8

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

[...]

-&gt; #3 (fs_reclaim){+.+.}-{0:0}:
       fs_reclaim_acquire.part.11+0x40/0x50
       fs_reclaim_acquire+0x24/0x28
       __kmalloc_track_caller+0x54/0x218
       kstrdup+0x40/0x5c
       create_regulator+0xf4/0x368
       regulator_resolve_supply+0x1a0/0x200
       regulator_register+0x9c8/0x163c

[...]

other info that might help us debug this:

Chain exists of:
  regulator_list_mutex --&gt; &amp;sit_i-&gt;sentry_lock --&gt; &amp;dcc-&gt;cmd_lock

[...]

Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/6eebc99b2474f4ffaa0405b15178ece0e7e4f608.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&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 87fe29b61f9522a3d7b60a4580851f548558186f upstream.

Move all allocations outside of the regulator_lock()ed section.

======================================================
WARNING: possible circular locking dependency detected
5.7.13+ #535 Not tainted
------------------------------------------------------
f2fs_discard-179:7/702 is trying to acquire lock:
c0e5d920 (regulator_list_mutex){+.+.}-{3:3}, at: regulator_lock_dependent+0x54/0x2c0

but task is already holding lock:
cb95b080 (&amp;dcc-&gt;cmd_lock){+.+.}-{3:3}, at: __issue_discard_cmd+0xec/0x5f8

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

[...]

-&gt; #3 (fs_reclaim){+.+.}-{0:0}:
       fs_reclaim_acquire.part.11+0x40/0x50
       fs_reclaim_acquire+0x24/0x28
       __kmalloc_track_caller+0x54/0x218
       kstrdup+0x40/0x5c
       create_regulator+0xf4/0x368
       regulator_resolve_supply+0x1a0/0x200
       regulator_register+0x9c8/0x163c

[...]

other info that might help us debug this:

Chain exists of:
  regulator_list_mutex --&gt; &amp;sit_i-&gt;sentry_lock --&gt; &amp;dcc-&gt;cmd_lock

[...]

Fixes: f8702f9e4aa7 ("regulator: core: Use ww_mutex for regulators locking")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/6eebc99b2474f4ffaa0405b15178ece0e7e4f608.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: push allocation in regulator_init_coupling() outside of lock</title>
<updated>2020-09-17T11:47:52+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-08-12T01:31:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=e7249ceb7ff83d19e1d13df397e67ae228d5b1e8'/>
<id>e7249ceb7ff83d19e1d13df397e67ae228d5b1e8</id>
<content type='text'>
commit 73a32129f8ccb556704a26b422f54e048bf14bd0 upstream.

Allocating memory with regulator_list_mutex held makes lockdep unhappy
when memory pressure makes the system do fs_reclaim on eg. eMMC using
a regulator. Push the lock inside regulator_init_coupling() after the
allocation.

======================================================
WARNING: possible circular locking dependency detected
5.7.13+ #533 Not tainted
------------------------------------------------------
kswapd0/383 is trying to acquire lock:
cca78ca4 (&amp;sbi-&gt;write_io[i][j].io_rwsem){++++}-{3:3}, at: __submit_merged_write_cond+0x104/0x154
but task is already holding lock:
c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-&gt; #2 (fs_reclaim){+.+.}-{0:0}:
       fs_reclaim_acquire.part.11+0x40/0x50
       fs_reclaim_acquire+0x24/0x28
       __kmalloc+0x54/0x218
       regulator_register+0x860/0x1584
       dummy_regulator_probe+0x60/0xa8
[...]
other info that might help us debug this:

Chain exists of:
  &amp;sbi-&gt;write_io[i][j].io_rwsem --&gt; regulator_list_mutex --&gt; fs_reclaim

Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               lock(regulator_list_mutex);
                               lock(fs_reclaim);
  lock(&amp;sbi-&gt;write_io[i][j].io_rwsem);
 *** DEADLOCK ***

1 lock held by kswapd0/383:
 #0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
[...]

Fixes: d8ca7d184b33 ("regulator: core: Introduce API for regulators coupling customization")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reviewed-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1a889cf7f61c6429c9e6b34ddcdde99be77a26b6.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&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 73a32129f8ccb556704a26b422f54e048bf14bd0 upstream.

Allocating memory with regulator_list_mutex held makes lockdep unhappy
when memory pressure makes the system do fs_reclaim on eg. eMMC using
a regulator. Push the lock inside regulator_init_coupling() after the
allocation.

======================================================
WARNING: possible circular locking dependency detected
5.7.13+ #533 Not tainted
------------------------------------------------------
kswapd0/383 is trying to acquire lock:
cca78ca4 (&amp;sbi-&gt;write_io[i][j].io_rwsem){++++}-{3:3}, at: __submit_merged_write_cond+0x104/0x154
but task is already holding lock:
c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-&gt; #2 (fs_reclaim){+.+.}-{0:0}:
       fs_reclaim_acquire.part.11+0x40/0x50
       fs_reclaim_acquire+0x24/0x28
       __kmalloc+0x54/0x218
       regulator_register+0x860/0x1584
       dummy_regulator_probe+0x60/0xa8
[...]
other info that might help us debug this:

Chain exists of:
  &amp;sbi-&gt;write_io[i][j].io_rwsem --&gt; regulator_list_mutex --&gt; fs_reclaim

Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(fs_reclaim);
                               lock(regulator_list_mutex);
                               lock(fs_reclaim);
  lock(&amp;sbi-&gt;write_io[i][j].io_rwsem);
 *** DEADLOCK ***

1 lock held by kswapd0/383:
 #0: c0e38518 (fs_reclaim){+.+.}-{0:0}, at: __fs_reclaim_acquire+0x0/0x50
[...]

Fixes: d8ca7d184b33 ("regulator: core: Introduce API for regulators coupling customization")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reviewed-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/1a889cf7f61c6429c9e6b34ddcdde99be77a26b6.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;

</pre>
</div>
</content>
</entry>
<entry>
<title>regulator: remove superfluous lock in regulator_resolve_coupling()</title>
<updated>2020-09-17T11:47:41+00:00</updated>
<author>
<name>Michał Mirosław</name>
<email>mirq-linux@rere.qmqm.pl</email>
</author>
<published>2020-08-12T01:31:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=25915590865ceee0d054d648921f553403a004d9'/>
<id>25915590865ceee0d054d648921f553403a004d9</id>
<content type='text'>
[ Upstream commit a577f3456c0a2fac3dee037c483753e6e68f3e49 ]

The code modifies rdev, but locks c_rdev instead. Remove the lock
as this is held together by regulator_list_mutex taken in the caller.

Fixes: f9503385b187 ("regulator: core: Mutually resolve regulators coupling")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reviewed-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Link: https://lore.kernel.org/r/25eb81cefb37a646f3e44eaaf1d8ae8881cfde52.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit a577f3456c0a2fac3dee037c483753e6e68f3e49 ]

The code modifies rdev, but locks c_rdev instead. Remove the lock
as this is held together by regulator_list_mutex taken in the caller.

Fixes: f9503385b187 ("regulator: core: Mutually resolve regulators coupling")
Signed-off-by: Michał Mirosław &lt;mirq-linux@rere.qmqm.pl&gt;
Reviewed-by: Dmitry Osipenko &lt;digetx@gmail.com&gt;
Link: https://lore.kernel.org/r/25eb81cefb37a646f3e44eaaf1d8ae8881cfde52.1597195321.git.mirq-linux@rere.qmqm.pl
Signed-off-by: Mark Brown &lt;broonie@kernel.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
