On Fri, Mar 14, 2025 at 08:56:49AM -0600, Alex Williamson wrote: > On Fri, 7 Mar 2025 16:03:49 +0200 > Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> wrote: > > > __resource_resize_store() attempts to release all resources of the > > device before attempting the resize. The loop, however, only covers > > standard BARs (< PCI_STD_NUM_BARS). If a device has VF BARs that are > > assigned, pci_reassign_bridge_resources() finds the bridge window still > > has some assigned child resources and returns -NOENT which makes > > pci_resize_resource() to detect an error and abort the resize. > > > > Change the release loop to cover all resources up to VF BARs which > > allows the resize operation to release the bridge windows and attempt > > to assigned them again with the different size. > > > > As __resource_resize_store() checks first that no driver is bound to > > the PCI device before resizing is allowed, SR-IOV cannot be enabled > > during resize so it is safe to release also the IOV resources. > > Is this true? pci-pf-stub doesn't teardown SR-IOV on release, which I > understand is done intentionally. Thanks, Is that really intentional? PCI warns when that scenario occurs: https://elixir.bootlin.com/linux/v6.13.7/source/drivers/pci/iov.c#L936 I thought that the usecase is binding pci-pf-stub, creating VFs, and letting the driver be. But unbinding after creating VFs? What's the goal of that? Perhaps we're just missing .remove() in pci-pf-stub? Thanks, -Michał > > Alex > > > Fixes: 91fa127794ac ("PCI: Expose PCIe Resizable BAR support via sysfs") > > Reported-by: Michał Winiarski <michal.winiarski@xxxxxxxxx> > > Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> > > --- > > > > v2: > > - Removed language about expansion ROMs > > > > drivers/pci/pci-sysfs.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/drivers/pci/pci-sysfs.c b/drivers/pci/pci-sysfs.c > > index b46ce1a2c554..0c16751bab40 100644 > > --- a/drivers/pci/pci-sysfs.c > > +++ b/drivers/pci/pci-sysfs.c > > @@ -1578,7 +1578,7 @@ static ssize_t __resource_resize_store(struct device *dev, int n, > > > > pci_remove_resource_files(pdev); > > > > - for (i = 0; i < PCI_STD_NUM_BARS; i++) { > > + for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) { > > if (pci_resource_len(pdev, i) && > > pci_resource_flags(pdev, i) == flags) > > pci_release_resource(pdev, i); > > > > base-commit: 2014c95afecee3e76ca4a56956a936e23283f05b >
