| Message ID | 1346800307-11041-1-git-send-email-Jiang.Wang@riverbed.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On Tue, Sep 4, 2012 at 5:11 PM, Jiang Wang <Jiang.Wang@riverbed.com> wrote: > When CONFIG_PCI_IOV is enabled, the kernel will call sriov_init(). > This function tries to allocate virtual resources even if the > virtual function of a PCI devive is not enabled by the BIOS. > > This sometimes causes following warning messages during boot up: > pci 0000:02:00.0: BAR 9: can't allocate mem resource [0x000000-0x3fffff] > pci 0000:02:00.0: BAR 7: can't allocate mem resource [0x000000-0x03ffff] > > Tested on three Mitac motherboards. > > Signed-off-by: Jiang Wang <jwang@riverbed.com> > --- > drivers/pci/iov.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c > index 6554e1a..0ca8cb2 100644 > --- a/drivers/pci/iov.c > +++ b/drivers/pci/iov.c > @@ -441,7 +441,8 @@ static int sriov_init(struct pci_dev *dev, int pos) > if (ctrl & PCI_SRIOV_CTRL_VFE) { > pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); > ssleep(1); > - } > + } else > + return 0; But this would mean that Linux can't *ever* enable VFs unless the BIOS enabled them, right? I don't think that's what we want -- there's code in sriov_enable() to turn on VFE, assuming we have enough resources for the VFs. It's certainly possible that the BIOS didn't allocate large enough apertures in the bridges leading to the SR-IOV device to accommodate all the VFs, and Linux may not be smart enough to enlarge them. And probably our warning messages in that case are not very enlightening. Bjorn > pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); > if (!total) > -- > 1.7.1 > -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
-----Original Message----- From: Bjorn Helgaas [mailto:bhelgaas@google.com] Sent: Tuesday, September 11, 2012 4:35 PM To: Jiang Wang Cc: linux-pci@vger.kernel.org; linux-kernel@vger.kernel.org; Chaitanya Lala; Francis St. Amant; Jiang Wang Subject: Re: [PATCH 1/1] pci-iov: Fix warnings when CONFIG_PCI_IOV is enabled On Tue, Sep 4, 2012 at 5:11 PM, Jiang Wang <Jiang.Wang@riverbed.com> wrote: > When CONFIG_PCI_IOV is enabled, the kernel will call sriov_init(). > This function tries to allocate virtual resources even if the virtual > function of a PCI devive is not enabled by the BIOS. > > This sometimes causes following warning messages during boot up: > pci 0000:02:00.0: BAR 9: can't allocate mem resource > [0x000000-0x3fffff] pci 0000:02:00.0: BAR 7: can't allocate mem > resource [0x000000-0x03ffff] > > Tested on three Mitac motherboards. > > Signed-off-by: Jiang Wang <jwang@riverbed.com> > --- > drivers/pci/iov.c | 3 ++- > 1 files changed, 2 insertions(+), 1 deletions(-) > > diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index > 6554e1a..0ca8cb2 100644 > --- a/drivers/pci/iov.c > +++ b/drivers/pci/iov.c > @@ -441,7 +441,8 @@ static int sriov_init(struct pci_dev *dev, int pos) > if (ctrl & PCI_SRIOV_CTRL_VFE) { > pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); > ssleep(1); > - } > + } else > + return 0; But this would mean that Linux can't *ever* enable VFs unless the BIOS enabled them, right? I don't think that's what we want -- there's code in sriov_enable() to turn on VFE, assuming we have enough resources for the VFs. --- I see. I didn't find the code in sriov_enable() before I send out the patch. Thanks for the info. It's certainly possible that the BIOS didn't allocate large enough apertures in the bridges leading to the SR-IOV device to accommodate all the VFs, and Linux may not be smart enough to enlarge them. And probably our warning messages in that case are not very enlightening. ---- My purpose here is to remove those warnings. I also tried to disable CONFIG_PCI_IOV, but that causes another strange problem on one of machines. The LSI controller cannot get memory resources and 32 LSI controllers shown up even though only one actually exist. I will drop this patch and do more debug to see what that problem is. Thanks. Bjorn > pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); > if (!total) > -- > 1.7.1 > Regards, Jiang -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c index 6554e1a..0ca8cb2 100644 --- a/drivers/pci/iov.c +++ b/drivers/pci/iov.c @@ -441,7 +441,8 @@ static int sriov_init(struct pci_dev *dev, int pos) if (ctrl & PCI_SRIOV_CTRL_VFE) { pci_write_config_word(dev, pos + PCI_SRIOV_CTRL, 0); ssleep(1); - } + } else + return 0; pci_read_config_word(dev, pos + PCI_SRIOV_TOTAL_VF, &total); if (!total)
When CONFIG_PCI_IOV is enabled, the kernel will call sriov_init(). This function tries to allocate virtual resources even if the virtual function of a PCI devive is not enabled by the BIOS. This sometimes causes following warning messages during boot up: pci 0000:02:00.0: BAR 9: can't allocate mem resource [0x000000-0x3fffff] pci 0000:02:00.0: BAR 7: can't allocate mem resource [0x000000-0x03ffff] Tested on three Mitac motherboards. Signed-off-by: Jiang Wang <jwang@riverbed.com> --- drivers/pci/iov.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)