From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Wed, 21 May 2014 21:56:31 +0000
Subject: Re: [PATCH v5 3/4] drivers/vfio: EEH support for VFIO PCI device
Message-Id: <1400709391.29150.24.camel@pasglop>
List-Id: <kvm-ppc.vger.kernel.org>
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 <1400648623-9127-4-git-send-email-gwshan@linux.vnet.ibm.com>
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To: Alexander Graf <agraf@suse.de>
Cc: aik@ozlabs.ru, Gavin Shan <gwshan@linux.vnet.ibm.com>, kvm-ppc@vger.kernel.org, alex.williamson@redhat.com, qiudayu@linux.vnet.ibm.com, linuxppc-dev@lists.ozlabs.org

On Wed, 2014-05-21 at 15:07 +0200, Alexander Graf wrote:

> > +#ifdef CONFIG_VFIO_PCI_EEH
> > +int eeh_vfio_open(struct pci_dev *pdev)
> 
> Why vfio? Also that config option will not be set if vfio is compiled as 
> a module.
> 
> > +{
> > +	struct eeh_dev *edev;
> > +
> > +	/* No PCI device ? */
> > +	if (!pdev)
> > +		return -ENODEV;
> > +
> > +	/* No EEH device ? */
> > +	edev = pci_dev_to_eeh_dev(pdev);
> > +	if (!edev || !edev->pe)
> > +		return -ENODEV;
> > +
> > +	eeh_dev_set_passed(edev, true);
> > +	eeh_pe_set_passed(edev->pe, true);
> > +
> > +	return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(eeh_vfio_open);

Additionally, shouldn't we have some locking here ? (and in release too)

I don't like relying on the caller locking (if it does it at all).

> > +	/* Device existing ? */
> > +	ret = eeh_vfio_check_dev(pdev, &edev, &pe);
> > +	if (ret) {
> > +		pr_debug("%s: Cannot find device %s\n",
> > +			__func__, pdev ? pci_name(pdev) : "NULL");
> > +		*retval = -7;
> 
> What are these? Please use proper kernel internal return values for 
> errors. I don't want to see anything even remotely tied to RTAS in any 
> of these patches.

Hint: -ENODEV

Cheers,
Ben.