Re: [PATCH v4 0/4] spi: cadence-qspi: Fix runtime PM and system-wide suspend

From: "Théo Lebrun" <theo.lebrun@bootlin.com>
To: "Mark Brown" <broonie@kernel.org>, "Dhruva Gole" <d-gole@ti.com>
Cc: "Apurva Nandan" <a-nandan@ti.com>, <linux-spi@vger.kernel.org>,
	<linux-kernel@vger.kernel.org>,
	"Gregory CLEMENT" <gregory.clement@bootlin.com>,
	"Vladimir Kondratiev" <vladimir.kondratiev@mobileye.com>,
	"Thomas Petazzoni" <thomas.petazzoni@bootlin.com>,
	"Tawfik Bayouk" <tawfik.bayouk@mobileye.com>,
	"Nishanth" <nm@ti.com>, "Vignesh" <vigneshr@ti.com>
Subject: Re: [PATCH v4 0/4] spi: cadence-qspi: Fix runtime PM and system-wide suspend
Date: Mon, 26 Feb 2024 14:42:51 +0100	[thread overview]
Message-ID: <CZF1Z7XP7TZD.3IY7CMWHUYZNC@bootlin.com> (raw)
In-Reply-To: <cb74a9f9-abfa-4a94-b4a9-bf41ddc697eb@sirena.org.uk>

Hello,

On Mon Feb 26, 2024 at 2:40 PM CET, Mark Brown wrote:
> On Mon, Feb 26, 2024 at 01:27:57PM +0000, Mark Brown wrote:
> > On Mon, Feb 26, 2024 at 05:48:03PM +0530, Dhruva Gole wrote:
> > > On Feb 22, 2024 at 19:13:29 +0000, Mark Brown wrote:
>
> > [    1.709414] Call trace:
> > [    1.711852]  __mutex_lock.constprop.0+0x84/0x540
> > [    1.716460]  __mutex_lock_slowpath+0x14/0x20
> > [    1.720719]  mutex_lock+0x48/0x54
> > [    1.724026]  spi_controller_suspend+0x30/0x7c
> > [    1.728377]  cqspi_suspend+0x1c/0x6c
> > [    1.731944]  pm_generic_runtime_suspend+0x2c/0x44
> > [    1.736640]  genpd_runtime_suspend+0xa8/0x254
>
> > (it's generally helpful to provide the most relevant section directly.)
>
> > The issue here appears to be that we've registered for runtime suspend
> > prior to registering the controller...
>
> Actually, no - after this series cqspi_suspend() is the system not
> runtime PM operation and should not be called from runtime suspend.  How
> is that happening?

You might have seen my answer by now. This series is not in the tags
quoted. I believe the memory corruption I fixed with this series is
being encountered for the first time on TI hardware. They probably did
not encounter it previously by luck.

Regards,

--
Théo Lebrun, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

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