From mboxrd@z Thu Jan  1 00:00:00 1970
From: lorenzo.pieralisi@arm.com (Lorenzo Pieralisi)
Date: Sun, 14 Jan 2018 12:20:37 +0000
Subject: [PATCH v6 11/16] firmware: arm_sdei: Add support for CPU and
 system power states
In-Reply-To: <20180113120031.5m6eykwzqnioyb33@armageddon.cambridge.arm.com>
References: <20180108153818.22743-1-james.morse@arm.com>
 <20180108153818.22743-12-james.morse@arm.com>
 <20180108172226.GC2530@red-moon>
 <20180113120031.5m6eykwzqnioyb33@armageddon.cambridge.arm.com>
Message-ID: <20180114122037.GA18073@red-moon>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Sat, Jan 13, 2018 at 12:00:31PM +0000, Catalin Marinas wrote:
> On Mon, Jan 08, 2018 at 05:22:26PM +0000, Lorenzo Pieralisi wrote:
> > On Mon, Jan 08, 2018 at 03:38:13PM +0000, James Morse wrote:
> > 
> > [...]
> > 
> > > +/* When entering idle, mask/unmask events for this cpu */
> > 
> > Just mentioning (since I know you know), this notifier is called also
> > through syscore_ops so it is not just idle (CPUidle or Suspend-to-idle).
> > 
> > > +static int sdei_pm_notifier(struct notifier_block *nb, unsigned long action,
> > > +			    void *data)
> > > +{
> > > +	int rv;
> > > +
> > > +	switch (action) {
> > > +	case CPU_PM_ENTER:
> > > +		rv = sdei_mask_local_cpu();
> > > +		break;
> > > +	case CPU_PM_EXIT:
> > > +		rv = sdei_unmask_local_cpu();
> > 
> > You should handle CPU_PM_ENTER_FAILED here for correctness,
> > in case the notifier chain fails.
> 
> So, just to confirm, the CPU_PM_ENTER_FAILED case goes together with
> CPU_PM_EXIT so that we unmask the SDE again for the CPU.

Yes, that's correct (I do not think that's a problem with current
mainline but that ought to be handled correctly anyway).

Lorenzo