linux-kernel - Re: [RFC PATCH v1 12/38] coco: host: arm64: CCA host platform device driver

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: <20250729232243.GK26511@ziepe.ca>
Date: Tue, 29 Jul 2025 20:22:43 -0300
From: Jason Gunthorpe <jgg@...pe.ca>
To: Jonathan Cameron <Jonathan.Cameron@...wei.com>
Cc: "Aneesh Kumar K.V (Arm)" <aneesh.kumar@...nel.org>,
	linux-coco@...ts.linux.dev, kvmarm@...ts.linux.dev,
	linux-pci@...r.kernel.org, linux-kernel@...r.kernel.org,
	aik@....com, lukas@...ner.de, Samuel Ortiz <sameo@...osinc.com>,
	Xu Yilun <yilun.xu@...ux.intel.com>,
	Suzuki K Poulose <Suzuki.Poulose@....com>,
	Steven Price <steven.price@....com>,
	Catalin Marinas <catalin.marinas@....com>,
	Marc Zyngier <maz@...nel.org>, Will Deacon <will@...nel.org>,
	Oliver Upton <oliver.upton@...ux.dev>
Subject: Re: [RFC PATCH v1 12/38] coco: host: arm64: CCA host platform device
 driver

On Tue, Jul 29, 2025 at 06:22:44PM +0100, Jonathan Cameron wrote:
> > +}
> 
> > +static void cca_tsm_remove(void *tsm_core)
> > +{
> > +	tsm_unregister(tsm_core);
> > +}
> > +
> > +static int cca_tsm_probe(struct platform_device *pdev)
> > +{
> > +	struct tsm_core_dev *tsm_core;
> > +
> > +	tsm_core = tsm_register(&pdev->dev, NULL, &cca_pci_ops);
> > +	if (IS_ERR(tsm_core))
> > +		return PTR_ERR(tsm_core);
> > +
> > +	return devm_add_action_or_reset(&pdev->dev, cca_tsm_remove, tsm_core);
> 
> So this makes two with the one in Dan's test code. 
> devm_tsm_register() seems to be a useful generic thing to add (implementation
> being exactly what you have here.

Pelase no, this is insane, you have a probed driver with a
probe/remove function pairing already. Why on earth would you use devm
just to call a remove function :(

Just put tsm_unregister() in the normal driver remove like it is
supposed to be done and use the drvdata to pass the tsm_core_dev
pointer. It is easy and normal, look at fwctl for a very simple
example.

devm is useful to solve complex things, these trivial things should be
done normally..

Jason