| Message ID | 1375773838-33572-1-git-send-email-wangyijing@huawei.com (mailing list archive) |
|---|---|
| State | New, archived |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
On 2013/8/6 15:23, Yijing Wang wrote: > v1->v2: Update patch log, remove Joe's reported-by, because his problem > was mainly caused by BIOS incorrect setting. But this patch mainly > to fix the bug caused by device hot add. Conservatively, this > version only update the mps problem when hot add. When the device > mps < parent mps found, this patch try to update device mps. > It seems unlikely device mps > parent mps after hot add device. > So we don't care that situation. > > This patch need to be applied to stable 3.4+ In this case... > > Currently we don't update device's mps vaule when doing > pci device hot-add. The hot-added device's mps will be set > to default value (128B). But the upstream port device's mps > may be larger than 128B which was set by firmware during > system bootup. In this case the new added device may not > work normally. This patch try to update the hot added device > mps euqal to its parent mps, if device mpss < parent mps, > print warning. > > References: https://bugzilla.kernel.org/show_bug.cgi?id=60671 > Reported-by: Yijing Wang <wangyijing@huawei.com> > Signed-off-by: Yijing Wang <wangyijing@huawei.com> > Cc: Jon Mason <jdmason@kudzu.us> > Cc: stable@vger.kernel.org The better tag is: Cc: <stable@vger.kernel.org> # 3.4+ Otherwise you won't be notified if it can be applied to the most recent stable version but failed in older versions. -- 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 2013/8/6 15:37, Li Zefan wrote: > On 2013/8/6 15:23, Yijing Wang wrote: >> v1->v2: Update patch log, remove Joe's reported-by, because his problem >> was mainly caused by BIOS incorrect setting. But this patch mainly >> to fix the bug caused by device hot add. Conservatively, this >> version only update the mps problem when hot add. When the device >> mps < parent mps found, this patch try to update device mps. >> It seems unlikely device mps > parent mps after hot add device. >> So we don't care that situation. >> >> This patch need to be applied to stable 3.4+ > > In this case... > >> >> Currently we don't update device's mps vaule when doing >> pci device hot-add. The hot-added device's mps will be set >> to default value (128B). But the upstream port device's mps >> may be larger than 128B which was set by firmware during >> system bootup. In this case the new added device may not >> work normally. This patch try to update the hot added device >> mps euqal to its parent mps, if device mpss < parent mps, >> print warning. >> >> References: https://bugzilla.kernel.org/show_bug.cgi?id=60671 >> Reported-by: Yijing Wang <wangyijing@huawei.com> >> Signed-off-by: Yijing Wang <wangyijing@huawei.com> >> Cc: Jon Mason <jdmason@kudzu.us> >> Cc: stable@vger.kernel.org > > The better tag is: > > Cc: <stable@vger.kernel.org> # 3.4+ > > Otherwise you won't be notified if it can be applied to the most recent > stable version but failed in older versions. Will update, thanks! > > > . >
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index cf57fe7..9b0e634 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1603,6 +1603,40 @@ static int pcie_bus_configure_set(struct pci_dev *dev, void *data) return 0; } +static int pcie_bus_update_set(struct pci_dev *dev, void *data) +{ + int mps, p_mps; + + if (!pci_is_pcie(dev) || !dev->bus->self) + return 0; + + mps = pcie_get_mps(dev); + p_mps = pcie_get_mps(dev->bus->self); + + if (mps < p_mps) + goto update; + + return 0; + +update: + /* If current mpss is lager than upstream, use upstream mps to update + * current mps, otherwise print warning info. + */ + if ((128 << dev->pcie_mpss) >= p_mps) + pcie_write_mps(dev, p_mps); + else + dev_warn(&dev->dev, "MPS %d MPSS %d both smaller than upstream MPS %d\n" + "If necessary, use \"pci=pcie_bus_peer2peer\" boot parameter to avoid this problem\n", + mps, 128 << dev->pcie_mpss, p_mps); + return 0; +} + +static void pcie_bus_update_setting(struct pci_bus *bus) +{ + if (bus->self->is_hotplug_bridge) + pci_walk_bus(bus, pcie_bus_update_set, NULL); +} + /* pcie_bus_configure_settings requires that pci_walk_bus work in a top-down, * parents then children fashion. If this changes, then this code will not * work as designed. @@ -1614,6 +1648,15 @@ void pcie_bus_configure_settings(struct pci_bus *bus, u8 mpss) if (!pci_is_pcie(bus->self)) return; + /* Sometimes we should update device mps here, + * eg. after hot add, device mps value will be + * set to default(128B), but the upstream port + * mps value may be larger than 128B, if we do + * not update the device mps, it maybe can not + * work normally. + */ + pcie_bus_update_setting(bus); + if (pcie_bus_config == PCIE_BUS_TUNE_OFF) return;
v1->v2: Update patch log, remove Joe's reported-by, because his problem was mainly caused by BIOS incorrect setting. But this patch mainly to fix the bug caused by device hot add. Conservatively, this version only update the mps problem when hot add. When the device mps < parent mps found, this patch try to update device mps. It seems unlikely device mps > parent mps after hot add device. So we don't care that situation. This patch need to be applied to stable 3.4+ Currently we don't update device's mps vaule when doing pci device hot-add. The hot-added device's mps will be set to default value (128B). But the upstream port device's mps may be larger than 128B which was set by firmware during system bootup. In this case the new added device may not work normally. This patch try to update the hot added device mps euqal to its parent mps, if device mpss < parent mps, print warning. References: https://bugzilla.kernel.org/show_bug.cgi?id=60671 Reported-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Yijing Wang <wangyijing@huawei.com> Cc: Jon Mason <jdmason@kudzu.us> Cc: stable@vger.kernel.org --- drivers/pci/probe.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 files changed, 43 insertions(+), 0 deletions(-)