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authorLinus Torvalds <torvalds@linux-foundation.org>2020-02-01 01:36:35 +0300
committerLinus Torvalds <torvalds@linux-foundation.org>2020-02-01 01:36:35 +0300
commitcf3c8f84d1401fed5010784034d104cc689061d5 (patch)
treef287526b311ff2e78df673cef667b8667b2deb0c /drivers/base
parenta62aa6f7f50a9a0af5e07d98774f8a7b439d390f (diff)
parent82b2c6ffd399c9fcd542fd681bb8c6d41f035c7e (diff)
downloadlinux-cf3c8f84d1401fed5010784034d104cc689061d5.tar.xz
Merge tag 'pm-5.6-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull more power manadement updates from Rafael Wysocki: "Prevent cpufreq from creating excessively large stack frames and fix the handling of devices deleted during system-wide resume in the PM core (Rafael Wysocki), revert a problematic commit affecting the cpupower utility and correct its man page (Thomas Renninger, Brahadambal Srinivasan), and improve the intel_pstate_tracer utility (Doug Smythies)" * tag 'pm-5.6-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: tools/power/x86/intel_pstate_tracer: change several graphs to autoscale y-axis tools/power/x86/intel_pstate_tracer: changes for python 3 compatibility Correction to manpage of cpupower cpufreq: Avoid creating excessively large stack frames PM: core: Fix handling of devices deleted during system-wide resume cpupower: Revert library ABI changes from commit ae2917093fb60bdc1ed3e
Diffstat (limited to 'drivers/base')
-rw-r--r--drivers/base/power/main.c42
1 files changed, 37 insertions, 5 deletions
diff --git a/drivers/base/power/main.c b/drivers/base/power/main.c
index 134a8af51511..0e99a760aebd 100644
--- a/drivers/base/power/main.c
+++ b/drivers/base/power/main.c
@@ -273,10 +273,38 @@ static void dpm_wait_for_suppliers(struct device *dev, bool async)
device_links_read_unlock(idx);
}
-static void dpm_wait_for_superior(struct device *dev, bool async)
+static bool dpm_wait_for_superior(struct device *dev, bool async)
{
- dpm_wait(dev->parent, async);
+ struct device *parent;
+
+ /*
+ * If the device is resumed asynchronously and the parent's callback
+ * deletes both the device and the parent itself, the parent object may
+ * be freed while this function is running, so avoid that by reference
+ * counting the parent once more unless the device has been deleted
+ * already (in which case return right away).
+ */
+ mutex_lock(&dpm_list_mtx);
+
+ if (!device_pm_initialized(dev)) {
+ mutex_unlock(&dpm_list_mtx);
+ return false;
+ }
+
+ parent = get_device(dev->parent);
+
+ mutex_unlock(&dpm_list_mtx);
+
+ dpm_wait(parent, async);
+ put_device(parent);
+
dpm_wait_for_suppliers(dev, async);
+
+ /*
+ * If the parent's callback has deleted the device, attempting to resume
+ * it would be invalid, so avoid doing that then.
+ */
+ return device_pm_initialized(dev);
}
static void dpm_wait_for_consumers(struct device *dev, bool async)
@@ -621,7 +649,8 @@ static int device_resume_noirq(struct device *dev, pm_message_t state, bool asyn
if (!dev->power.is_noirq_suspended)
goto Out;
- dpm_wait_for_superior(dev, async);
+ if (!dpm_wait_for_superior(dev, async))
+ goto Out;
skip_resume = dev_pm_may_skip_resume(dev);
@@ -829,7 +858,8 @@ static int device_resume_early(struct device *dev, pm_message_t state, bool asyn
if (!dev->power.is_late_suspended)
goto Out;
- dpm_wait_for_superior(dev, async);
+ if (!dpm_wait_for_superior(dev, async))
+ goto Out;
callback = dpm_subsys_resume_early_cb(dev, state, &info);
@@ -944,7 +974,9 @@ static int device_resume(struct device *dev, pm_message_t state, bool async)
goto Complete;
}
- dpm_wait_for_superior(dev, async);
+ if (!dpm_wait_for_superior(dev, async))
+ goto Complete;
+
dpm_watchdog_set(&wd, dev);
device_lock(dev);