On Mon, 27 Jul 2020 12:23:58 +0100 Jonathan Cameron <[email protected]> wrote:
> 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); This needs updating as well to match current approach in Bjorn's tree (reworked version of my fix for this in th !is_native case) > > + pci_aer_clear_nonfatal_status(dev->rcec); > > These may be safe as in my both now have protections for !pcie_aer_is_native. Except I'm wrong. That function performs a local check based on the pci_dev passed in, so blows up anyway. So this whole block needs an if(dev->rcec), or potentially protect it with a call to pci_aer_is_native(dev) on the basis we shouldn't be able to get here unless we are not doing native aer or we have an rcec. Jonathan > > > } > > + > > 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 */ >
