Re: [PATCH v1 4/5] PCI: Adapt all code locations to not use struct pci_dev::driver directly - Uwe Kleine-König

From: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
To: Boris Ostrovsky <boris.ostrovsky@oracle.com>
Cc: "Bjorn Helgaas" <bhelgaas@google.com>,
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Subject: Re: [PATCH v1 4/5] PCI: Adapt all code locations to not use struct pci_dev::driver directly
Date: Sat, 31 Jul 2021 14:08:36 +0200	[thread overview]
Message-ID: <20210731120836.vegno6voijvlflws@pengutronix.de> (raw)
In-Reply-To: <2b5e8cb5-fac2-5da2-f87b-d287d2c5ea81@oracle.com>

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Hello Boris,

On Fri, Jul 30, 2021 at 04:37:31PM -0400, Boris Ostrovsky wrote:
> On 7/29/21 4:37 PM, Uwe Kleine-König wrote:
> > --- a/drivers/pci/xen-pcifront.c
> > +++ b/drivers/pci/xen-pcifront.c
> > @@ -599,12 +599,12 @@ static pci_ers_result_t pcifront_common_process(int cmd,
> >  	result = PCI_ERS_RESULT_NONE;
> >  
> >  	pcidev = pci_get_domain_bus_and_slot(domain, bus, devfn);
> > -	if (!pcidev || !pcidev->driver) {
> > +	pdrv = pci_driver_of_dev(pcidev);
> > +	if (!pcidev || !pdrv) {
> 
> If pcidev is NULL we are dead by the time we reach 'if' statement.

Oh, you're right. So this needs something like:

	if (!pcidev || !(pdrv = pci_driver_of_dev(pcidev)))

or repeating the call to pci_driver_of_dev for each previous usage of
pdev->driver.

If there are no other preferences I'd got with the first approach for
v2.

Best regards and thanks for catching,
Uwe

-- 
Pengutronix e.K.                           | Uwe Kleine-König            |
Industrial Linux Solutions                 | https://www.pengutronix.de/ |

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