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

From: Boris Ostrovsky <boris.ostrovsky@oracle.com>
To: "Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>
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Subject: Re: [PATCH v1 4/5] PCI: Adapt all code locations to not use struct pci_dev::driver directly
Date: Mon, 2 Aug 2021 09:06:34 -0400	[thread overview]
Message-ID: <d9dfe855-a2a5-c48b-b4c4-8109d7289809@oracle.com> (raw)
In-Reply-To: <20210731120836.vegno6voijvlflws@pengutronix.de>

On 7/31/21 8:08 AM, Uwe Kleine-König wrote:
> 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)))

Sure, that's fine. And while at it please also drop 'if (pdrv)' check below (it's not directly related to your change but is more noticeable now so since you are in that function anyway I'd appreciate if you could do that).

Thanks.

-boris

>
> 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
>