11084836e5
commit 81b704d3e4674e09781d331df73d76675d5ad8cb upstream.
Calling acpi_thermal_check() from acpi_thermal_notify() directly
is problematic if _TMP triggers Notify () on the thermal zone for
which it has been evaluated (which happens on some systems), because
it causes a new acpi_thermal_notify() invocation to be queued up
every time and if that takes place too often, an indefinite number of
pending work items may accumulate in kacpi_notify_wq over time.
Besides, it is not really useful to queue up a new invocation of
acpi_thermal_check() if one of them is pending already.
For these reasons, rework acpi_thermal_notify() to queue up a thermal
check instead of calling acpi_thermal_check() directly and only allow
one thermal check to be pending at a time. Moreover, only allow one
acpi_thermal_check_fn() instance at a time to run
thermal_zone_device_update() for one thermal zone and make it return
early if it sees other instances running for the same thermal zone.
While at it, fold acpi_thermal_check() into acpi_thermal_check_fn(),
as it is only called from there after the other changes made here.
[This issue appears to have been exposed by commit 6d25be5782e4
("sched/core, workqueues: Distangle worker accounting from rq
lock"), but it is unclear why it was not visible earlier.]
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=208877
Reported-by: Stephen Berman <stephen.berman@gmx.net>
Diagnosed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Tested-by: Stephen Berman <stephen.berman@gmx.net>
Cc: All applicable <stable@vger.kernel.org>
[bigeasy: Backported to v5.4.y]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
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In order to build the documentation, use ``make htmldocs`` or
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There are various text files in the Documentation/ subdirectory,
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