[PATCH 0/2 v2] sh-sci / PM: Fix problem with runtime PM callbacks run with interrupts off

From: "Rafael J. Wysocki" <rjw@sisk.pl>
To: linux-sh@vger.kernel.org
Cc: Linux PM mailing list <linux-pm@lists.linux-foundation.org>,
	LKML <linux-kernel@vger.kernel.org>,
	Magnus Damm <magnus.damm@gmail.com>,
	Alan Stern <stern@rowland.harvard.edu>
Subject: [PATCH 0/2 v2] sh-sci / PM: Fix problem with runtime PM callbacks run with interrupts off
Date: Sun, 21 Aug 2011 19:09:30 +0000	[thread overview]
Message-ID: <201108212109.30399.rjw@sisk.pl> (raw)
In-Reply-To: <201108202131.19479.rjw@sisk.pl>

Hi,

> The sh-sci driver uses pm_runtime_get/put_sync() in such a way
> that they may be run with interrupts off and cause the (recently
> added) might_sleep_if() to trigger in rpm_suspend/resume().
> 
> To avoid that, it's necessary to set the SCI device's power.irq_safe
> flag to indicate that it's runtime PM callbacks may be executed with
> interrupts off safely.  However, the sh-sci driver needs to be able to
> clear that flag sometimes, so a new runtime PM helper for doing that
> is needed.

The previous version of this patchset was not very good as Alan pointed out,
so hopefully this one will be better.

[1/2] - Change PM subsys_data lock type into spinlock.
[2/2] - Make sh-sci use power.irq_safe to indicate that runtime PM callbacks
        may be run with interrupts off.

Thanks,
Rafael