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PM: runtime: Do not call __rpm_callback() from rpm_idle()

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[ Upstream commit bc80c2e438dcbfcf748452ec0f7ad5b79ff3ad88 ]

Calling __rpm_callback() from rpm_idle() after adding device links
support to the former is a clear mistake.

Not only it causes rpm_idle() to carry out unnecessary actions, but it
is also against the assumption regarding the stability of PM-runtime
status across __rpm_callback() invocations, because rpm_suspend() and
rpm_resume() may run in parallel with __rpm_callback() when it is called
by rpm_idle() and the device's PM-runtime status can be updated by any
of them.

Fixes: 21d5c57b37 ("PM / runtime: Use device links")
Link: https://lore.kernel.org/linux-pm/36aed941-a73e-d937-2721-4f0decd61ce0@quicinc.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Rafael J. Wysocki 2022-12-02 15:30:28 +01:00 committed by Greg Kroah-Hartman
parent c40ee4e04b
commit 11ad95912b
1 changed files with 11 additions and 1 deletions
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12
drivers/base/power/runtime.c
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@ -465,7 +465,17 @@ static int rpm_idle(struct device *dev, int rpmflags)
dev->power.idle_notification = true;
retval = __rpm_callback(callback, dev);
if (dev->power.irq_safe)
spin_unlock(&dev->power.lock);
else
spin_unlock_irq(&dev->power.lock);
retval = callback(dev);
if (dev->power.irq_safe)
spin_lock(&dev->power.lock);
else
spin_lock_irq(&dev->power.lock);
dev->power.idle_notification = false;
wake_up_all(&dev->power.wait_queue);