Re: [PATCH v4 2/3] PCI: endpoint: Fix error handling in pci_epc_epf_link()

Kishon Vijay Abraham I
2017-12-14T12:14:28Z

On Thursday 14 December 2017 05:37 PM, Lorenzo Pieralisi wrote:
> On Thu, Dec 14, 2017 at 04:37:22PM +0530, Kishon Vijay Abraham I wrote:
>> Hi Niklas,
>>
>> On Tuesday 12 December 2017 07:46 PM, Niklas Cassel wrote:
>>> The error handling in pci_epc_epf_link() is broken,
>>> since the clean up code for pci_epc_add_epf() calls clear_bit(),
>>> even though the matching set_bit() is done after pci_epc_add_epf().
>>>
>>> Also, clear_bit() should be done before pci_epc_remove_epf(),
>>> since clean up code should normally do things in the reverse order.
>>>
>>> Fixes: d74679911610 ("PCI: endpoint: Introduce configfs entry for configuring EP functions")
>>> Signed-off-by: Niklas Cassel <niklas.cassel@axis.com>
>>> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
>>> ---
>>> drivers/pci/endpoint/pci-ep-cfs.c | 6 ++----
>>> 1 file changed, 2 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/drivers/pci/endpoint/pci-ep-cfs.c b/drivers/pci/endpoint/pci-ep-cfs.c
>>> index 4f74386c1ced..e1f5adc9e113 100644
>>> --- a/drivers/pci/endpoint/pci-ep-cfs.c
>>> +++ b/drivers/pci/endpoint/pci-ep-cfs.c
>>> @@ -106,7 +106,7 @@ static int pci_epc_epf_link(struct config_item *epc_item,
>>> epf = epf_group->epf;
>>> ret = pci_epc_add_epf(epc, epf);
>>> if (ret)
>>> - goto err_add_epf;
>>> + return ret;
>>
>> Actually the func_no should be populated before invoking pci_epc_add_epf. Once
>> that is done, the error handling should be fine.
>
> Which means that current code works because pci_epc_add_epf() is called
> with epf->func_no == 0 right ? I agree that the correct fix consists in

that's right Lorenzo.

Thanks
Kishon