| Message ID | 66bbf8b3-bab9-1860-12c9-1c187ddc4201@solarflare.com |
|---|---|
| State | Accepted |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | pci/vpd: Ensure VPD is checked before timeout | expand |
On Thu, Jul 26, 2018 at 04:21:29PM +0100, Bert Kenward wrote: > We check the timeout before we check the VPD access completion bit. > On a very heavily loaded system this can cause VPD access to timeout. > We should check the completion bit before checking the timeout. > > Signed-off-by: Bert Kenward <bkenward@solarflare.com> Applied to pci/misc for v4.19, thanks! > --- > drivers/pci/vpd.c | 7 +++++-- > 1 file changed, 5 insertions(+), 2 deletions(-) > > diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c > index 8617565ba561..4963c2e2bd4c 100644 > --- a/drivers/pci/vpd.c > +++ b/drivers/pci/vpd.c > @@ -146,7 +146,7 @@ static int pci_vpd_wait(struct pci_dev *dev) > if (!vpd->busy) > return 0; > > - while (time_before(jiffies, timeout)) { > + do { > ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR, > &status); > if (ret < 0) > @@ -160,10 +160,13 @@ static int pci_vpd_wait(struct pci_dev *dev) > if (fatal_signal_pending(current)) > return -EINTR; > > + if (time_after(jiffies, timeout)) > + break; > + > usleep_range(10, max_sleep); > if (max_sleep < 1024) > max_sleep *= 2; > - } > + } while (true); > > pci_warn(dev, "VPD access failed. This is likely a firmware bug on this device. Contact the card vendor for a firmware update\n"); > return -ETIMEDOUT; > -- > 2.13.6 >
diff --git a/drivers/pci/vpd.c b/drivers/pci/vpd.c index 8617565ba561..4963c2e2bd4c 100644 --- a/drivers/pci/vpd.c +++ b/drivers/pci/vpd.c @@ -146,7 +146,7 @@ static int pci_vpd_wait(struct pci_dev *dev) if (!vpd->busy) return 0; - while (time_before(jiffies, timeout)) { + do { ret = pci_user_read_config_word(dev, vpd->cap + PCI_VPD_ADDR, &status); if (ret < 0) @@ -160,10 +160,13 @@ static int pci_vpd_wait(struct pci_dev *dev) if (fatal_signal_pending(current)) return -EINTR; + if (time_after(jiffies, timeout)) + break; + usleep_range(10, max_sleep); if (max_sleep < 1024) max_sleep *= 2; - } + } while (true); pci_warn(dev, "VPD access failed. This is likely a firmware bug on this device. Contact the card vendor for a firmware update\n"); return -ETIMEDOUT;
We check the timeout before we check the VPD access completion bit. On a very heavily loaded system this can cause VPD access to timeout. We should check the completion bit before checking the timeout. Signed-off-by: Bert Kenward <bkenward@solarflare.com> --- drivers/pci/vpd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)