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From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Linux PM <linux-pm@vger.kernel.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
 LKML <linux-kernel@vger.kernel.org>, Lukasz Luba <lukasz.luba@arm.com>,
 Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
 Zhang Rui <rui.zhang@intel.com>
Subject:
 [PATCH v1 0/2] thermal: core: Fix two issues related to thermal zone resume
Date: Fri, 14 Jun 2024 17:17:35 +0200
Message-ID: <6070114.lOV4Wx5bFT@kreacher>
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Hi Everyone,

There are two issues resulting from asynchronous suspend of thermal zones.

One of them is platform-specific and related to some firmware issue (I think)
causing battery readings to become invalid after a system resume due to
interference between ACPI battery resume and a thermal zone update.  This
can be addressed by running the thermal PM notifier after all of the other
PM notifiers (including the ACPI battery one) which is done by patch [2/2].

The other one is mostly theoretical, but I couldn't convince myself that it
cannot happen.  Namely, a leftover thermal zone resume running during the
next system suspend (if it is carried out back-to-back with the previous
suspend-resume cycle) can accidentally reset tz->suspended set for a thermal
zone by the thermal pre-suspend PM notifier.  This is addressed by patch
[1/2] (which goes before the second one because the latter increases the
likelihood of the issue slightly).

Thanks!