linux-kernel - Re: [PATCH 4/6] iio: imu: inv_icm42600: Simplify pm

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aG-DGEpZOHqFoIY3@smile.fi.intel.com>
Date: Thu, 10 Jul 2025 12:08:40 +0300
From: Andy Shevchenko <andriy.shevchenko@...el.com>
To: Sean Nyekjaer <sean@...nix.com>
Cc: Jean-Baptiste Maneyrol <jean-baptiste.maneyrol@....com>,
	Jonathan Cameron <jic23@...nel.org>,
	David Lechner <dlechner@...libre.com>,
	Nuno Sá <nuno.sa@...log.com>,
	Andy Shevchenko <andy@...nel.org>, linux-iio@...r.kernel.org,
	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 4/6] iio: imu: inv_icm42600: Simplify pm_runtime setup

On Wed, Jul 09, 2025 at 02:35:12PM +0200, Sean Nyekjaer wrote:
> Remove unnecessary pm_runtime_get_noresume() and pm_runtime_put()
> calls during probe. These are not required when the device is marked
> active via pm_runtime_set_active() before enabling pm_runtime with
> pm_runtime_enable().

Hmm... What will happen if the autosuspend triggers just before going out from
the probe when this change is applied?

> Also remove the redundant pm_runtime_put_sync() call from the cleanup
> path, since the core is not incrementing the usage count beforehand.

This is interesting. Have anybody actually tried to see refcount WARN about this?

> This simplifies the PM setup and avoids manipulating the usage counter
> unnecessarily.

> Fixes: 31c24c1e93c3 ("iio: imu: inv_icm42600: add core of new inv_icm42600 driver")
> Signed-off-by: Sean Nyekjaer <sean@...nix.com>

This should be the first, or close to the beginning of the series, patch.

-- 
With Best Regards,
Andy Shevchenko