| Message ID | 20130507213250.GA22773@google.com |
|---|---|
| State | Accepted |
| Headers | show |
On Tue, May 7, 2013 at 2:32 PM, Bjorn Helgaas <bhelgaas@google.com> wrote: > On Thu, Apr 25, 2013 at 06:47:07PM -0700, Yinghai Lu wrote: >> David found some resource conflict issue after >> | PCI: Put pci_dev in device tree as early as possible >> | commit 4f535093cf8f6da8cfda7c36c2c1ecd2e9586ee4 >> >> and >> | USB: Fix handoff when BIOS disables host PCI device >> | commit: cab928ee1f221c9cc48d6615070fefe2e444384a >> >> for usb qirks for hotplug path. >> >> After checking pci_fixup_device() with pci_fixup_final, >> now we have different path for boot path and hotadd path. >> >> Boot path: because pci_apply_fix_final_quirks is not set yet, >> so pci_fixup_device(pci_fixup_final) will be skipped >> from pci_device_add(). >> And later pci_apply_final_quirks will be called for all >> pci devices via fs_initcall. >> That is after pci_assign_unassign resource. >> In that case quirk could use bars with problem. >> >> Hotadd path: pci_fixup_device(pci_fixup_final) will be executed >> via pci_device_add(), and that is too early for hotplug >> path, as pci bar for hot add devices is not assigned yet >> after commit 4f535093. >> >> So we need to move down that for hotplug path, call that in >> pci_bus_add_devices instead, as at that time just before >> drivers get attached. >> And that is simliar calling place for pci_device_add before >> commit 4f535093 is applied. >> >> We should apply this fix for v3.9, but is too late now. >> so get it into v3.10 and could get into v3.9 stable instead. >> >> Reported-by: David Bulkow <David.Bulkow@stratus.com> >> Tested-by: David Bulkow <David.Bulkow@stratus.com> >> Signed-off-by: Yinghai Lu <yinghai@kernel.org> > > I applied the following slightly tweaked patch to for-linus and will > ask Linus to pull it for v3.10. Let me know if it looks OK. > > Bjorn > > commit a939563f3fd9cd6226c7fb7135d0b93507c53888 > Author: Bjorn Helgaas <bhelgaas@google.com> (I did already fix the Author: to be Yinghai, sorry about that) > Date: Tue May 7 14:35:44 2013 -0600 > > PCI: Delay final fixups until resources are assigned > > Commit 4f535093cf "PCI: Put pci_dev in device tree as early as possible" > moved final fixups from pci_bus_add_device() to pci_device_add(). But > pci_device_add() happens before resource assignment, so BARs may not be > valid yet. > > Typical flow for hot-add: > > pciehp_configure_device > pci_scan_slot > pci_scan_single_device > pci_device_add > pci_fixup_device(pci_fixup_final, dev) # previous location > # resource assignment happens here > pci_bus_add_devices > pci_bus_add_device > pci_fixup_device(pci_fixup_final, dev) # new location > > [bhelgaas: changelog, move fixups to pci_bus_add_device()] > Reference: https://lkml.kernel.org/r/20130415182614.GB9224@xanatos > Reported-by: David Bulkow <David.Bulkow@stratus.com> > Tested-by: David Bulkow <David.Bulkow@stratus.com> > Signed-off-by: Yinghai Lu <yinghai@kernel.org> > Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> > CC: stable@vger.kernel.org # v3.9+ > > diff --git a/drivers/pci/bus.c b/drivers/pci/bus.c > index 748f8f3..32e66a6 100644 > --- a/drivers/pci/bus.c > +++ b/drivers/pci/bus.c > @@ -174,6 +174,7 @@ int pci_bus_add_device(struct pci_dev *dev) > * Can not put in pci_device_add yet because resources > * are not assigned yet for some devices. > */ > + pci_fixup_device(pci_fixup_final, dev); > pci_create_sysfs_dev_files(dev); > > dev->match_driver = true; > diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c > index 43ece5d..67cd045 100644 > --- a/drivers/pci/probe.c > +++ b/drivers/pci/probe.c > @@ -1341,7 +1341,6 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) > list_add_tail(&dev->bus_list, &bus->devices); > up_write(&pci_bus_sem); > > - pci_fixup_device(pci_fixup_final, dev); > ret = pcibios_add_device(dev); > WARN_ON(ret < 0); > -- 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
On Tue, May 7, 2013 at 2:38 PM, Bjorn Helgaas <bhelgaas@google.com> wrote: > On Tue, May 7, 2013 at 2:32 PM, Bjorn Helgaas <bhelgaas@google.com> wrote: >> >> PCI: Delay final fixups until resources are assigned >> >> Commit 4f535093cf "PCI: Put pci_dev in device tree as early as possible" >> moved final fixups from pci_bus_add_device() to pci_device_add(). But >> pci_device_add() happens before resource assignment, so BARs may not be >> valid yet. >> >> Typical flow for hot-add: >> >> pciehp_configure_device >> pci_scan_slot >> pci_scan_single_device >> pci_device_add >> pci_fixup_device(pci_fixup_final, dev) # previous location >> # resource assignment happens here >> pci_bus_add_devices >> pci_bus_add_device >> pci_fixup_device(pci_fixup_final, dev) # new location >> >> [bhelgaas: changelog, move fixups to pci_bus_add_device()] Yes, that is right fix. Thanks Yinghai -- 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/bus.c b/drivers/pci/bus.c index 748f8f3..32e66a6 100644 --- a/drivers/pci/bus.c +++ b/drivers/pci/bus.c @@ -174,6 +174,7 @@ int pci_bus_add_device(struct pci_dev *dev) * Can not put in pci_device_add yet because resources * are not assigned yet for some devices. */ + pci_fixup_device(pci_fixup_final, dev); pci_create_sysfs_dev_files(dev); dev->match_driver = true; diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 43ece5d..67cd045 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1341,7 +1341,6 @@ void pci_device_add(struct pci_dev *dev, struct pci_bus *bus) list_add_tail(&dev->bus_list, &bus->devices); up_write(&pci_bus_sem); - pci_fixup_device(pci_fixup_final, dev); ret = pcibios_add_device(dev); WARN_ON(ret < 0);