Re: [bug report] PCI: endpoint: Remove "core_init_notifier" flag

[Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>]

On Wed, Apr 17, 2024 at 05:38:05PM +0200, Niklas Cassel wrote:
> On Wed, Apr 17, 2024 at 03:47:48PM +0300, Dan Carpenter wrote:
> > Hello Manivannan Sadhasivam,
> > 
> > Commit a01e7214bef9 ("PCI: endpoint: Remove "core_init_notifier"
> > flag") from Mar 27, 2024 (linux-next), leads to the following Smatch
> > static checker warning:
> > 
> > 	drivers/pci/endpoint/functions/pci-epf-test.c:784 pci_epf_test_core_init()
> > 	error: we previously assumed 'epc_features' could be null (see line 747)
> > 
> > drivers/pci/endpoint/functions/pci-epf-test.c
> >     734 static int pci_epf_test_core_init(struct pci_epf *epf)
> >     735 {
> >     736         struct pci_epf_test *epf_test = epf_get_drvdata(epf);
> >     737         struct pci_epf_header *header = epf->header;
> >     738         const struct pci_epc_features *epc_features;
> >     739         struct pci_epc *epc = epf->epc;
> >     740         struct device *dev = &epf->dev;
> >     741         bool linkup_notifier = false;
> >     742         bool msix_capable = false;
> >     743         bool msi_capable = true;
> >     744         int ret;
> 
> We check pci_epc_get_features() in ->bind(), which comes before ->core_init()
> so in practice, this shouldn't be able to be NULL here.
> 

Right.

> 
> >     745 
> >     746         epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no);
> >     747         if (epc_features) {
> >                     ^^^^^^^^^^^^
> > epc_features can be NULL
> 
> We should probably just chge this to:
> 
> """
> if (!epc_features)
> 	return some_error;
> 
> msix_capable = epc_features->msix_capable;
> msi_capable = epc_features->msi_capable;
> """
> 
> Such that we don't need another check further down for linkup_notifier.
> 

No. We should just remove this NULL check since the check is already present in
bind().

- Mani

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