public inbox for linux-pm@vger.kernel.org
 help / color / mirror / Atom feed
From: "Rafael J. Wysocki" <rjw@rjwysocki.net>
To: Linux PM <linux-pm@vger.kernel.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>,
	Linux ACPI <linux-acpi@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	"Rafael J. Wysocki" <rafael@kernel.org>,
	Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
	Zhang Rui <rui.zhang@intel.com>,
	Lukasz Luba <lukasz.luba@arm.com>
Subject: [PATCH v1] thermal: trip: Drop lockdep assertion from thermal_zone_trip_id()
Date: Wed, 11 Oct 2023 17:55:27 +0200	[thread overview]
Message-ID: <12311623.O9o76ZdvQC@kreacher> (raw)

From: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

The lockdep assertion in thermal_zone_trip_id() triggers when the
trip point sysfs attribute of a thermal instance is read, because
there is no thermal zone locking in that code path.

This is not verly useful, though, because there is no mechanism by which
the location of the trips[] table in a thermal zone or its size can
change after binding cooling devices to the trips in that thermal
zone and before those cooling devices are unbound from them.  Thus
it is not in fact necessary to hold the thermal zone lock when
thermal_zone_trip_id() is called from trip_point_show() and so the
lockdep asserion in the former is invalid.

Accordingly, drop that lockdep assertion.

Fixes: 2c7b4bfadef0 ("thermal: core: Store trip pointer in struct thermal_instance")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
---

The commit mentioned above is in linux-next at this time.

---
 drivers/thermal/thermal_trip.c |    2 --
 1 file changed, 2 deletions(-)

Index: linux-pm/drivers/thermal/thermal_trip.c
===================================================================
--- linux-pm.orig/drivers/thermal/thermal_trip.c
+++ linux-pm/drivers/thermal/thermal_trip.c
@@ -175,8 +175,6 @@ int thermal_zone_trip_id(struct thermal_
 {
 	int i;
 
-	lockdep_assert_held(&tz->lock);
-
 	for (i = 0; i < tz->num_trips; i++) {
 		if (&tz->trips[i] == trip)
 			return i;




                 reply	other threads:[~2023-10-11 15:55 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=12311623.O9o76ZdvQC@kreacher \
    --to=rjw@rjwysocki.net \
    --cc=daniel.lezcano@linaro.org \
    --cc=linux-acpi@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pm@vger.kernel.org \
    --cc=lukasz.luba@arm.com \
    --cc=rafael@kernel.org \
    --cc=rui.zhang@intel.com \
    --cc=srinivas.pandruvada@linux.intel.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox