Re: [PATCH v4 2/7] PCI: Ignore BAR updates on virtual functions
From: Gavin Shan <hidden>
Date: 2016-11-29 04:44:40
Also in:
linux-pci
On Mon, Nov 28, 2016 at 10:14:29PM -0600, Bjorn Helgaas wrote:
VF BARs are read-only zero, so updating VF BARs will not have any effect.
See the SR-IOV spec r1.1, sec 3.4.1.11.
We already ignore these updates because of 70675e0b6a1a ("PCI: Don't try to
restore VF BARs"); this merely restructures it slightly to make it easier
to split updates for standard and SR-IOV BARs.
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: Wei Yang <redacted>Reviewed-by: Gavin Shan <redacted>
quoted hunk ↗ jump to hunk
--- drivers/pci/pci.c | 4 ---- drivers/pci/setup-res.c | 5 ++--- 2 files changed, 2 insertions(+), 7 deletions(-)diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index ba34907..631eac2 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c@@ -564,10 +564,6 @@ static void pci_restore_bars(struct pci_dev *dev){ int i; - /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */ - if (dev->is_virtfn) - return; - for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) pci_update_resource(dev, i); }diff --git a/drivers/pci/setup-res.c b/drivers/pci/setup-res.c index 66c4d8f..d2a32d8 100644 --- a/drivers/pci/setup-res.c +++ b/drivers/pci/setup-res.c@@ -36,10 +36,9 @@ void pci_update_resource(struct pci_dev *dev, int resno)enum pci_bar_type type; struct resource *res = dev->resource + resno; - if (dev->is_virtfn) { - dev_warn(&dev->dev, "can't update VF BAR%d\n", resno); + /* Per SR-IOV spec 3.4.1.11, VF BARs are RO zero */ + if (dev->is_virtfn) return; - } /* * Ignore resources for unimplemented BARs and unused resource slots