Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge tag 'pm-5.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix a NULL pointer dereference in a devfreq driver and a runtime
PM framework issue that may cause a supplier device to be suspended
before its consumer.
Specifics:
- Fix NULL pointer dereference related to printing a diagnostic
message in the exynos-bus devfreq driver (Christian Marangi)
- Fix race condition in the runtime PM framework which in some cases
may cause a supplier device to be suspended when its consumer is
still active (Rafael Wysocki)"
* tag 'pm-5.19-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM / devfreq: exynos-bus: Fix NULL pointer dereference
PM: runtime: Fix supplier device management during consumer probe
PM: runtime: Redefine pm_runtime_release_supplier()
+27
-31
+12
-1
drivers/base/core.c
+12
-1
drivers/base/core.c
···
486
486
/* Ensure that all references to the link object have been dropped. */
487
487
device_link_synchronize_removal();
488
488
489
-
pm_runtime_release_supplier(link, true);
489
+
pm_runtime_release_supplier(link);
490
+
/*
491
+
* If supplier_preactivated is set, the link has been dropped between
492
+
* the pm_runtime_get_suppliers() and pm_runtime_put_suppliers() calls
493
+
* in __driver_probe_device(). In that case, drop the supplier's
494
+
* PM-runtime usage counter to remove the reference taken by
495
+
* pm_runtime_get_suppliers().
496
+
*/
497
+
if (link->supplier_preactivated)
498
+
pm_runtime_put_noidle(link->supplier);
499
+
500
+
pm_request_idle(link->supplier);
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501
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put_device(link->consumer);
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503
put_device(link->supplier);
+10
-24
drivers/base/power/runtime.c
+10
-24
drivers/base/power/runtime.c
···
308
308
/**
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* pm_runtime_release_supplier - Drop references to device link's supplier.
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* @link: Target device link.
311
-
* @check_idle: Whether or not to check if the supplier device is idle.
312
311
*
313
-
* Drop all runtime PM references associated with @link to its supplier device
314
-
* and if @check_idle is set, check if that device is idle (and so it can be
315
-
* suspended).
312
+
* Drop all runtime PM references associated with @link to its supplier device.
316
313
*/
317
-
void pm_runtime_release_supplier(struct device_link *link, bool check_idle)
314
+
void pm_runtime_release_supplier(struct device_link *link)
318
315
{
319
316
struct device *supplier = link->supplier;
320
317
···
324
327
while (refcount_dec_not_one(&link->rpm_active) &&
325
328
atomic_read(&supplier->power.usage_count) > 0)
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329
pm_runtime_put_noidle(supplier);
327
-
328
-
if (check_idle)
329
-
pm_request_idle(supplier);
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330
}
331
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static void __rpm_put_suppliers(struct device *dev, bool try_to_suspend)
···
331
337
struct device_link *link;
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338
333
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list_for_each_entry_rcu(link, &dev->links.suppliers, c_node,
334
-
device_links_read_lock_held())
335
-
pm_runtime_release_supplier(link, try_to_suspend);
340
+
device_links_read_lock_held()) {
341
+
pm_runtime_release_supplier(link);
342
+
if (try_to_suspend)
343
+
pm_request_idle(link->supplier);
344
+
}
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345
}
337
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347
static void rpm_put_suppliers(struct device *dev)
···
1768
1771
if (link->flags & DL_FLAG_PM_RUNTIME) {
1769
1772
link->supplier_preactivated = true;
1770
1773
pm_runtime_get_sync(link->supplier);
1771
-
refcount_inc(&link->rpm_active);
1772
1774
}
1773
1775
1774
1776
device_links_read_unlock(idx);
···
1787
1791
list_for_each_entry_rcu(link, &dev->links.suppliers, c_node,
1788
1792
device_links_read_lock_held())
1789
1793
if (link->supplier_preactivated) {
1790
-
bool put;
1791
-
1792
1794
link->supplier_preactivated = false;
1793
-
1794
-
spin_lock_irq(&dev->power.lock);
1795
-
1796
-
put = pm_runtime_status_suspended(dev) &&
1797
-
refcount_dec_not_one(&link->rpm_active);
1798
-
1799
-
spin_unlock_irq(&dev->power.lock);
1800
-
1801
-
if (put)
1802
-
pm_runtime_put(link->supplier);
1795
+
pm_runtime_put(link->supplier);
1803
1796
}
1804
1797
1805
1798
device_links_read_unlock(idx);
···
1823
1838
return;
1824
1839
1825
1840
pm_runtime_drop_link_count(link->consumer);
1826
-
pm_runtime_release_supplier(link, true);
1841
+
pm_runtime_release_supplier(link);
1842
+
pm_request_idle(link->supplier);
1827
1843
}
1828
1844
1829
1845
static bool pm_runtime_need_not_resume(struct device *dev)
+3
-3
drivers/devfreq/exynos-bus.c
+3
-3
drivers/devfreq/exynos-bus.c
···
447
447
}
448
448
}
449
449
450
-
max_state = bus->devfreq->profile->max_state;
451
-
min_freq = (bus->devfreq->profile->freq_table[0] / 1000);
452
-
max_freq = (bus->devfreq->profile->freq_table[max_state - 1] / 1000);
450
+
max_state = bus->devfreq->max_state;
451
+
min_freq = (bus->devfreq->freq_table[0] / 1000);
452
+
max_freq = (bus->devfreq->freq_table[max_state - 1] / 1000);
453
453
pr_info("exynos-bus: new bus device registered: %s (%6ld KHz ~ %6ld KHz)\n",
454
454
dev_name(dev), min_freq, max_freq);
455
455
+2
-3
include/linux/pm_runtime.h
+2
-3
include/linux/pm_runtime.h
···
88
88
extern void pm_runtime_put_suppliers(struct device *dev);
89
89
extern void pm_runtime_new_link(struct device *dev);
90
90
extern void pm_runtime_drop_link(struct device_link *link);
91
-
extern void pm_runtime_release_supplier(struct device_link *link, bool check_idle);
91
+
extern void pm_runtime_release_supplier(struct device_link *link);
92
92
93
93
extern int devm_pm_runtime_enable(struct device *dev);
94
94
···
314
314
static inline void pm_runtime_put_suppliers(struct device *dev) {}
315
315
static inline void pm_runtime_new_link(struct device *dev) {}
316
316
static inline void pm_runtime_drop_link(struct device_link *link) {}
317
-
static inline void pm_runtime_release_supplier(struct device_link *link,
318
-
bool check_idle) {}
317
+
static inline void pm_runtime_release_supplier(struct device_link *link) {}
319
318
320
319
#endif /* !CONFIG_PM */
321
320