On Fri, 24 Jul 2020 10:22:20 -0700 Sean V Kelley <[email protected]> wrote:
> From: Qiuxu Zhuo <[email protected]> > > When attempting error recovery for an RCiEP associated with an RCEC device, > there needs to be a way to update the Root Error Status, the Uncorrectable > Error Status and the Uncorrectable Error Severity of the parent RCEC. > So add the 'rcec' field to the pci_dev structure and provide a hook for the > Root Port Driver to associate RCiEPs with their respective parent RCEC. > > Co-developed-by: Sean V Kelley <[email protected]> > Signed-off-by: Qiuxu Zhuo <[email protected]> > Signed-off-by: Sean V Kelley <[email protected]> I haven't tested yet, but I think there is one path in here that breaks my case (no OS visible rcec / all done in firmware GHESv2 / APEI) Jonathan > --- > drivers/pci/pcie/aer.c | 9 +++++---- > drivers/pci/pcie/err.c | 9 +++++++++ > drivers/pci/pcie/portdrv_pci.c | 15 +++++++++++++++ > include/linux/pci.h | 3 +++ > 4 files changed, 32 insertions(+), 4 deletions(-) > > diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c > index 3acf56683915..f1bf06be449e 100644 > --- a/drivers/pci/pcie/aer.c > +++ b/drivers/pci/pcie/aer.c > @@ -1335,17 +1335,18 @@ static int aer_probe(struct pcie_device *dev) > static pci_ers_result_t aer_root_reset(struct pci_dev *dev) > { > int aer = dev->aer_cap; > + int rc = 0; > u32 reg32; > - int rc; > - > > /* Disable Root's interrupt in response to error messages */ > pci_read_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, ®32); > reg32 &= ~ROOT_PORT_INTR_ON_MESG_MASK; > pci_write_config_dword(dev, aer + PCI_ERR_ROOT_COMMAND, reg32); > > - rc = pci_bus_error_reset(dev); > - pci_info(dev, "Root Port link has been reset\n"); > + if (pci_pcie_type(dev) != PCI_EXP_TYPE_RC_EC) { > + rc = pci_bus_error_reset(dev); > + pci_info(dev, "Root Port link has been reset\n"); > + } > > /* Clear Root Error Status */ > pci_read_config_dword(dev, aer + PCI_ERR_ROOT_STATUS, ®32); > diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c > index 9b3ec94bdf1d..0aae7643132e 100644 > --- a/drivers/pci/pcie/err.c > +++ b/drivers/pci/pcie/err.c > @@ -203,6 +203,11 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > pci_walk_dev_affected(dev, report_frozen_detected, &status); > if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) { > status = flr_on_rciep(dev); > + /* > + * The callback only clears the Root Error Status > + * of the RCEC (see aer.c). > + */ > + reset_link(dev->rcec); This looks dangerous for my case where APEI / GHESv2 is used. In that case we don't expose an RCEC at all. I don't think the reset_link callback is safe to a null pointer here. Fix may be as simple as if (dev->rcec) reset_link(dev->rcec); > if (status != PCI_ERS_RESULT_RECOVERED) { > pci_warn(dev, "function level reset failed\n"); > goto failed; > @@ -246,7 +251,11 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, > pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC)) { > pci_aer_clear_device_status(dev); > pci_aer_clear_nonfatal_status(dev); > + } else if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_END) { > + pci_aer_clear_device_status(dev->rcec); > + pci_aer_clear_nonfatal_status(dev->rcec); These may be safe as in my both now have protections for !pcie_aer_is_native. > } > + > pci_info(dev, "device recovery successful\n"); > return status; > > diff --git a/drivers/pci/pcie/portdrv_pci.c b/drivers/pci/pcie/portdrv_pci.c > index d5b109499b10..f9409a0110c2 100644 > --- a/drivers/pci/pcie/portdrv_pci.c > +++ b/drivers/pci/pcie/portdrv_pci.c > @@ -90,6 +90,18 @@ static const struct dev_pm_ops pcie_portdrv_pm_ops = { > #define PCIE_PORTDRV_PM_OPS NULL > #endif /* !PM */ > > +static int pcie_hook_rcec(struct pci_dev *pdev, void *data) > +{ > + struct pci_dev *rcec = (struct pci_dev *)data; > + > + pdev->rcec = rcec; > + pci_info(rcec, "RCiEP(under an RCEC) %04x:%02x:%02x.%d\n", > + pci_domain_nr(pdev->bus), pdev->bus->number, > + PCI_SLOT(pdev->devfn), PCI_FUNC(pdev->devfn)); We may want to make this debug info at somepoint if we have a way of discovering it from userspace. The PCI boot up is extremely verbose already! > + > + return 0; > +} > + > /* > * pcie_portdrv_probe - Probe PCI-Express port devices > * @dev: PCI-Express port device being probed > @@ -110,6 +122,9 @@ static int pcie_portdrv_probe(struct pci_dev *dev, > (pci_pcie_type(dev) != PCI_EXP_TYPE_RC_EC))) > return -ENODEV; > > + if (pci_pcie_type(dev) == PCI_EXP_TYPE_RC_EC) > + pcie_walk_rcec(dev, pcie_hook_rcec, dev); > + > status = pcie_port_device_register(dev); > if (status) > return status; > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 34c1c4f45288..e920f29df40b 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -326,6 +326,9 @@ struct pci_dev { > #ifdef CONFIG_PCIEAER > u16 aer_cap; /* AER capability offset */ > struct aer_stats *aer_stats; /* AER stats for this device */ > +#endif > +#ifdef CONFIG_PCIEPORTBUS > + struct pci_dev *rcec; /* Associated RCEC device */ > #endif > u8 pcie_cap; /* PCIe capability offset */ > u8 msi_cap; /* MSI capability offset */
