linux-stable.git/drivers/base/power, branch v5.15.78

PM: domains: Fix handling of unavailable/disabled idle states

2022-11-03T14:59:18+00:00

[ Upstream commit e0c57a5c70c13317238cb19a7ded0eab4a5f7de5 ]

Platforms can provide the information about the availability of each
idle states via status flag. Platforms may have to disable one or more
idle states for various reasons like broken firmware or other unmet
dependencies.

Fix handling of such unavailable/disabled idle states by ignoring them
while parsing the states.

Fixes: a3381e3a65cb ("PM / domains: Fix up domain-idle-states OF parsing")
Signed-off-by: Sudeep Holla 
Reviewed-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: domains: Ensure genpd_debugfs_dir exists before remove

2022-08-17T12:23:13+00:00

[ Upstream commit 37101d3c719386040ded735a5ec06974f1d94d1f ]

Both genpd_debug_add() and genpd_debug_remove() may be called
indirectly by other drivers while genpd_debugfs_dir is not yet
set. For example, drivers can call pm_genpd_init() in probe or
pm_genpd_init() in probe fail/cleanup path:

pm_genpd_init()
 --> genpd_debug_add()

pm_genpd_remove()
 --> genpd_remove()
   --> genpd_debug_remove()

At this time, genpd_debug_init() may not yet be called.

genpd_debug_add() checks that if genpd_debugfs_dir is NULL, it
will return directly. Make sure this is also checked
in pm_genpd_remove(), otherwise components under debugfs root
which has the same name as other components under pm_genpd may
be accidentally removed, since NULL represents debugfs root.

Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains")
Signed-off-by: Hsin-Yi Wang 
Reviewed-by: Greg Kroah-Hartman 
Reviewed-by: AngeloGioacchino Del Regno 
Reviewed-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: runtime: Redefine pm_runtime_release_supplier()

2022-07-12T14:35:09+00:00

commit 07358194badf73e267289b40b761f5dc56928eab upstream.

Instead of passing an extra bool argument to pm_runtime_release_supplier(),
make its callers take care of triggering a runtime-suspend of the
supplier device as needed.

No expected functional impact.

Suggested-by: Greg Kroah-Hartman 
Signed-off-by: Rafael J. Wysocki 
Reviewed-by: Greg Kroah-Hartman 
Cc: 5.1+  # 5.1+
Signed-off-by: Greg Kroah-Hartman

PM: domains: Fix initialization of genpd's next_wakeup

2022-06-09T08:23:01+00:00

[ Upstream commit 622d9b5577f19a6472db21df042fea8f5fefe244 ]

In the genpd governor we walk the list of child-domains to take into
account their next_wakeup. If the child-domain itself, doesn't have a
governor assigned to it, we can end up using the next_wakeup value before
it has been properly initialized. To prevent a possible incorrect behaviour
in the governor, let's initialize next_wakeup to KTIME_MAX.

Fixes: c79aa080fb0f ("PM: domains: use device's next wakeup to determine domain idle state")
Signed-off-by: Ulf Hansson 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

rtc: Check return value from mc146818_get_time()

2022-04-13T18:59:14+00:00

[ Upstream commit 0dd8d6cb9eddfe637bcd821bbfd40ebd5a0737b9 ]

There are 4 users of mc146818_get_time() and none of them was checking
the return value from this function. Change this.

Print the appropriate warnings in callers of mc146818_get_time() instead
of in the function mc146818_get_time() itself, in order not to add
strings to rtc-mc146818-lib.c, which is kind of a library.

The callers of alpha_rtc_read_time() and cmos_read_time() may use the
contents of (struct rtc_time *) even when the functions return a failure
code. Therefore, set the contents of (struct rtc_time *) to 0x00,
which looks more sensible then 0xff and aligns with the (possibly
stale?) comment in cmos_read_time:

	/*
	 * If pm_trace abused the RTC for storage, set the timespec to 0,
	 * which tells the caller that this RTC value is unusable.
	 */

For consistency, do this in mc146818_get_time().

Note: hpet_rtc_interrupt() may call mc146818_get_time() many times a
second. It is very unlikely, though, that the RTC suddenly stops
working and mc146818_get_time() would consistently fail.

Only compile-tested on alpha.

Signed-off-by: Mateusz Jończyk 
Cc: Richard Henderson 
Cc: Ivan Kokshaysky 
Cc: Matt Turner 
Cc: Thomas Gleixner 
Cc: Ingo Molnar 
Cc: Borislav Petkov 
Cc: Dave Hansen 
Cc: Alessandro Zummo 
Cc: Alexandre Belloni 
Cc: linux-alpha@vger.kernel.org
Cc: x86@kernel.org
Signed-off-by: Alexandre Belloni 
Link: https://lore.kernel.org/r/20211210200131.153887-4-mat.jonczyk@o2.pl
Signed-off-by: Sasha Levin

PM: core: keep irq flags in device_pm_check_callbacks()

2022-04-08T12:23:56+00:00

[ Upstream commit 524bb1da785a7ae43dd413cd392b5071c6c367f8 ]

The function device_pm_check_callbacks() can be called under the spin
lock (in the reported case it happens from genpd_add_device() ->
dev_pm_domain_set(), when the genpd uses spinlocks rather than mutexes.

However this function uncoditionally uses spin_lock_irq() /
spin_unlock_irq(), thus not preserving the CPU flags. Use the
irqsave/irqrestore instead.

The backtrace for the reference:
[    2.752010] ------------[ cut here ]------------
[    2.756769] raw_local_irq_restore() called with IRQs enabled
[    2.762596] WARNING: CPU: 4 PID: 1 at kernel/locking/irqflag-debug.c:10 warn_bogus_irq_restore+0x34/0x50
[    2.772338] Modules linked in:
[    2.775487] CPU: 4 PID: 1 Comm: swapper/0 Tainted: G S                5.17.0-rc6-00384-ge330d0d82eff-dirty #684
[    2.781384] Freeing initrd memory: 46024K
[    2.785839] pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    2.785841] pc : warn_bogus_irq_restore+0x34/0x50
[    2.785844] lr : warn_bogus_irq_restore+0x34/0x50
[    2.785846] sp : ffff80000805b7d0
[    2.785847] x29: ffff80000805b7d0 x28: 0000000000000000 x27: 0000000000000002
[    2.785850] x26: ffffd40e80930b18 x25: ffff7ee2329192b8 x24: ffff7edfc9f60800
[    2.785853] x23: ffffd40e80930b18 x22: ffffd40e80930d30 x21: ffff7edfc0dffa00
[    2.785856] x20: ffff7edfc09e3768 x19: 0000000000000000 x18: ffffffffffffffff
[    2.845775] x17: 6572206f74206465 x16: 6c696166203a3030 x15: ffff80008805b4f7
[    2.853108] x14: 0000000000000000 x13: ffffd40e809550b0 x12: 00000000000003d8
[    2.860441] x11: 0000000000000148 x10: ffffd40e809550b0 x9 : ffffd40e809550b0
[    2.867774] x8 : 00000000ffffefff x7 : ffffd40e809ad0b0 x6 : ffffd40e809ad0b0
[    2.875107] x5 : 000000000000bff4 x4 : 0000000000000000 x3 : 0000000000000000
[    2.882440] x2 : 0000000000000000 x1 : 0000000000000000 x0 : ffff7edfc03a8000
[    2.889774] Call trace:
[    2.892290]  warn_bogus_irq_restore+0x34/0x50
[    2.896770]  _raw_spin_unlock_irqrestore+0x94/0xa0
[    2.901690]  genpd_unlock_spin+0x20/0x30
[    2.905724]  genpd_add_device+0x100/0x2d0
[    2.909850]  __genpd_dev_pm_attach+0xa8/0x23c
[    2.914329]  genpd_dev_pm_attach_by_id+0xc4/0x190
[    2.919167]  genpd_dev_pm_attach_by_name+0x3c/0xd0
[    2.924086]  dev_pm_domain_attach_by_name+0x24/0x30
[    2.929102]  psci_dt_attach_cpu+0x24/0x90
[    2.933230]  psci_cpuidle_probe+0x2d4/0x46c
[    2.937534]  platform_probe+0x68/0xe0
[    2.941304]  really_probe.part.0+0x9c/0x2fc
[    2.945605]  __driver_probe_device+0x98/0x144
[    2.950085]  driver_probe_device+0x44/0x15c
[    2.954385]  __device_attach_driver+0xb8/0x120
[    2.958950]  bus_for_each_drv+0x78/0xd0
[    2.962896]  __device_attach+0xd8/0x180
[    2.966843]  device_initial_probe+0x14/0x20
[    2.971144]  bus_probe_device+0x9c/0xa4
[    2.975092]  device_add+0x380/0x88c
[    2.978679]  platform_device_add+0x114/0x234
[    2.983067]  platform_device_register_full+0x100/0x190
[    2.988344]  psci_idle_init+0x6c/0xb0
[    2.992113]  do_one_initcall+0x74/0x3a0
[    2.996060]  kernel_init_freeable+0x2fc/0x384
[    3.000543]  kernel_init+0x28/0x130
[    3.004132]  ret_from_fork+0x10/0x20
[    3.007817] irq event stamp: 319826
[    3.011404] hardirqs last  enabled at (319825): [] __up_console_sem+0x78/0x84
[    3.020332] hardirqs last disabled at (319826): [] el1_dbg+0x24/0x8c
[    3.028458] softirqs last  enabled at (318312): [] _stext+0x410/0x588
[    3.036678] softirqs last disabled at (318299): [] __irq_exit_rcu+0x158/0x174
[    3.045607] ---[ end trace 0000000000000000 ]---

Signed-off-by: Dmitry Baryshkov 
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Sasha Levin

PM: domains: Fix sleep-in-atomic bug caused by genpd_debug_remove()

2022-04-08T12:23:02+00:00

commit f6bfe8b5b2c2a5ac8bd2fc7bca3706e6c3fc26d8 upstream.

When a genpd with GENPD_FLAG_IRQ_SAFE gets removed, the following
sleep-in-atomic bug will be seen, as genpd_debug_remove() will be called
with a spinlock being held.

[    0.029183] BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:1460
[    0.029204] in_atomic(): 1, irqs_disabled(): 128, non_block: 0, pid: 1, name: swapper/0
[    0.029219] preempt_count: 1, expected: 0
[    0.029230] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.17.0-rc4+ #489
[    0.029245] Hardware name: Thundercomm TurboX CM2290 (DT)
[    0.029256] Call trace:
[    0.029265]  dump_backtrace.part.0+0xbc/0xd0
[    0.029285]  show_stack+0x3c/0xa0
[    0.029298]  dump_stack_lvl+0x7c/0xa0
[    0.029311]  dump_stack+0x18/0x34
[    0.029323]  __might_resched+0x10c/0x13c
[    0.029338]  __might_sleep+0x4c/0x80
[    0.029351]  down_read+0x24/0xd0
[    0.029363]  lookup_one_len_unlocked+0x9c/0xcc
[    0.029379]  lookup_positive_unlocked+0x10/0x50
[    0.029392]  debugfs_lookup+0x68/0xac
[    0.029406]  genpd_remove.part.0+0x12c/0x1b4
[    0.029419]  of_genpd_remove_last+0xa8/0xd4
[    0.029434]  psci_cpuidle_domain_probe+0x174/0x53c
[    0.029449]  platform_probe+0x68/0xe0
[    0.029462]  really_probe+0x190/0x430
[    0.029473]  __driver_probe_device+0x90/0x18c
[    0.029485]  driver_probe_device+0x40/0xe0
[    0.029497]  __driver_attach+0xf4/0x1d0
[    0.029508]  bus_for_each_dev+0x70/0xd0
[    0.029523]  driver_attach+0x24/0x30
[    0.029534]  bus_add_driver+0x164/0x22c
[    0.029545]  driver_register+0x78/0x130
[    0.029556]  __platform_driver_register+0x28/0x34
[    0.029569]  psci_idle_init_domains+0x1c/0x28
[    0.029583]  do_one_initcall+0x50/0x1b0
[    0.029595]  kernel_init_freeable+0x214/0x280
[    0.029609]  kernel_init+0x2c/0x13c
[    0.029622]  ret_from_fork+0x10/0x20

It doesn't seem necessary to call genpd_debug_remove() with the lock, so
move it out from locking to fix the problem.

Fixes: 718072ceb211 ("PM: domains: create debugfs nodes when adding power domains")
Signed-off-by: Shawn Guo 
Reviewed-by: Ulf Hansson 
Cc: 5.11+  # 5.11+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM: s2idle: ACPI: Fix wakeup interrupts handling

2022-02-16T11:56:19+00:00

commit cb1f65c1e1424a4b5e4a86da8aa3b8fd8459c8ec upstream.

After commit e3728b50cd9b ("ACPI: PM: s2idle: Avoid possible race
related to the EC GPE") wakeup interrupts occurring immediately after
the one discarded by acpi_s2idle_wake() may be missed.  Moreover, if
the SCI triggers again immediately after the rearming in
acpi_s2idle_wake(), that wakeup may be missed too.

The problem is that pm_system_irq_wakeup() only calls pm_system_wakeup()
when pm_wakeup_irq is 0, but that's not the case any more after the
interrupt causing acpi_s2idle_wake() to run until pm_wakeup_irq is
cleared by the pm_wakeup_clear() call in s2idle_loop().  However,
there may be wakeup interrupts occurring in that time frame and if
that happens, they will be missed.

To address that issue first move the clearing of pm_wakeup_irq to
the point at which it is known that the interrupt causing
acpi_s2idle_wake() to tun will be discarded, before rearming the SCI
for wakeup.  Moreover, because that only reduces the size of the
time window in which the issue may manifest itself, allow
pm_system_irq_wakeup() to register two second wakeup interrupts in
a row and, when discarding the first one, replace it with the second
one.  [Of course, this assumes that only one wakeup interrupt can be
discarded in one go, but currently that is the case and I am not
aware of any plans to change that.]

Fixes: e3728b50cd9b ("ACPI: PM: s2idle: Avoid possible race related to the EC GPE")
Cc: 5.4+  # 5.4+
Signed-off-by: Rafael J. Wysocki 
Signed-off-by: Greg Kroah-Hartman

PM: runtime: Add safety net to supplier device release

2022-01-27T10:04:44+00:00

[ Upstream commit d1579e61192e0e686faa4208500ef4c3b529b16c ]

Because refcount_dec_not_one() returns true if the target refcount
becomes saturated, it is generally unsafe to use its return value as
a loop termination condition, but that is what happens when a device
link's supplier device is released during runtime PM suspend
operations and on device link removal.

To address this, introduce pm_runtime_release_supplier() to be used
in the above cases which will check the supplier device's runtime
PM usage counter in addition to the refcount_dec_not_one() return
value, so the loop can be terminated in case the rpm_active refcount
value becomes invalid, and update the code in question to use it as
appropriate.

This change is not expected to have any visible functional impact.

Reported-by: Peter Zijlstra 
Signed-off-by: Rafael J. Wysocki 
Acked-by: Greg Kroah-Hartman 
Acked-by: Peter Zijlstra (Intel) 
Signed-off-by: Sasha Levin

PM: sleep: Fix error handling in dpm_prepare()

2021-12-29T11:28:38+00:00

commit 544e737dea5ad1a457f25dbddf68761ff25e028b upstream.

Commit 2aa36604e824 ("PM: sleep: Avoid calling put_device() under
dpm_list_mtx") forgot to update the while () loop termination
condition to also break the loop if error is nonzero, which
causes the loop to become infinite if device_prepare() returns
an error for one device.

Add the missing !error check.

Fixes: 2aa36604e824 ("PM: sleep: Avoid calling put_device() under dpm_list_mtx")
Signed-off-by: Rafael J. Wysocki 
Reported-by: Thomas Hellström 
Reviewed-by: Thomas Hellström 
Reviewed-by: Ulf Hansson 
Cc: All applicable 
Signed-off-by: Greg Kroah-Hartman