On Wed, Apr 17, 2024 at 10:47:25PM +0530, Manivannan Sadhasivam wrote: > Instead of getting the epc_features from pci_epc_get_features() API, use > the cached pci_epf_test::epc_features value to avoid the NULL check. Since > the NULL check is already performed in pci_epf_test_bind(), having one more > check in pci_epf_test_core_init() is redundant and it is not possible to > hit the NULL pointer dereference. This also leads to the following smatch > 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) > > Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> > Closes: https://lore.kernel.org/linux-pci/024b5826-7180-4076-ae08-57d2584cca3f@moroto.mountain/ > Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> I think you forgot: Fixes: a01e7214bef9 ("PCI: endpoint: Remove "core_init_notifier" flag") > --- > drivers/pci/endpoint/functions/pci-epf-test.c | 9 ++++----- > 1 file changed, 4 insertions(+), 5 deletions(-) > > diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c > index 977fb79c1567..0d28f413cb07 100644 > --- a/drivers/pci/endpoint/functions/pci-epf-test.c > +++ b/drivers/pci/endpoint/functions/pci-epf-test.c > @@ -743,11 +743,10 @@ static int pci_epf_test_core_init(struct pci_epf *epf) > bool msi_capable = true; > int ret; > > - epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no); > - if (epc_features) { > - msix_capable = epc_features->msix_capable; > - msi_capable = epc_features->msi_capable; > - } > + epc_features = epf_test->epc_features; How about: index 977fb79c1567..4d6105c07ac0 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -735,7 +735,7 @@ static int pci_epf_test_core_init(struct pci_epf *epf) { struct pci_epf_test *epf_test = epf_get_drvdata(epf); struct pci_epf_header *header = epf->header; - const struct pci_epc_features *epc_features; + const struct pci_epc_features *epc_features = epf_test->epc_features; struct pci_epc *epc = epf->epc; struct device *dev = &epf->dev; bool linkup_notifier = false; @@ -743,12 +743,6 @@ static int pci_epf_test_core_init(struct pci_epf *epf) bool msi_capable = true; int ret; - epc_features = pci_epc_get_features(epc, epf->func_no, epf->vfunc_no); - if (epc_features) { - msix_capable = epc_features->msix_capable; - msi_capable = epc_features->msi_capable; - } - if (epf->vfunc_no <= 1) { ret = pci_epc_write_header(epc, epf->func_no, epf->vfunc_no, header); if (ret) { @@ -761,6 +755,7 @@ static int pci_epf_test_core_init(struct pci_epf *epf) if (ret) return ret; + msi_capable = epc_features->msi_capable; if (msi_capable) { ret = pci_epc_set_msi(epc, epf->func_no, epf->vfunc_no, epf->msi_interrupts); @@ -770,6 +765,7 @@ static int pci_epf_test_core_init(struct pci_epf *epf) } } + msix_capable = epc_features->msix_capable; if (msix_capable) { ret = pci_epc_set_msix(epc, epf->func_no, epf->vfunc_no, epf->msix_interrupts, @@ -814,11 +810,9 @@ static int pci_epf_test_alloc_space(struct pci_epf *epf) void *base; enum pci_barno test_reg_bar = epf_test->test_reg_bar; enum pci_barno bar; - const struct pci_epc_features *epc_features; + const struct pci_epc_features *epc_features = epf_test->epc_features; size_t test_reg_size; - epc_features = epf_test->epc_features; - test_reg_bar_size = ALIGN(sizeof(struct pci_epf_test_reg), 128); msix_capable = epc_features->msix_capable; Instead? That way, we assign msi_capable/msix_capable just before the if-statement where it is used. (Which matches how we already assign msix_capable just before the if-statement in pci_epf_test_alloc_space().) Kind regards, Niklas > + > + msix_capable = epc_features->msix_capable; > + msi_capable = epc_features->msi_capable; > > if (epf->vfunc_no <= 1) { > ret = pci_epc_write_header(epc, epf->func_no, epf->vfunc_no, header); > > --- > base-commit: 6e47dcb2ca223211c43c37497836cd9666c70674 > change-id: 20240417-pci-epf-test-fix-2209ae22be80 > > Best regards, > -- > Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> >
