From: Sean V Kelley sean.v.kelley@intel.com
mainline inclusion from mainline-v5.11-rc1 commit 05e9ae19ab83 category: feature bugzilla: https://gitee.com/openeuler/kernel/issues/I51U4T CVE: NA
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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Consolidate subordinate bus checks with pci_walk_bus() into pci_walk_bridge() for walking below potentially AER affected bridges.
Link: https://lore.kernel.org/r/20201121001036.8560-10-sean.v.kelley@intel.com Tested-by: Jonathan Cameron Jonathan.Cameron@huawei.com # non-native/no RCEC Signed-off-by: Sean V Kelley sean.v.kelley@intel.com Signed-off-by: Bjorn Helgaas bhelgaas@google.com Signed-off-by: Jiefeng Ou oujiefeng@h-partners.com Reviewed-by: Jay Fang f.fangjian@huawei.com Reviewed-by: Xiongfeng Wang wangxiongfeng2@huawei.com Signed-off-by: Zheng Zengkai zhengzengkai@huawei.com --- drivers/pci/pcie/err.c | 30 +++++++++++++++++++++++------- 1 file changed, 23 insertions(+), 7 deletions(-)
diff --git a/drivers/pci/pcie/err.c b/drivers/pci/pcie/err.c index 931e75f2549d..8b53aecdb43d 100644 --- a/drivers/pci/pcie/err.c +++ b/drivers/pci/pcie/err.c @@ -146,13 +146,30 @@ static int report_resume(struct pci_dev *dev, void *data) return 0; }
+/** + * pci_walk_bridge - walk bridges potentially AER affected + * @bridge: bridge which may be a Port + * @cb: callback to be called for each device found + * @userdata: arbitrary pointer to be passed to callback + * + * If the device provided is a bridge, walk the subordinate bus, including + * any bridged devices on buses under this bus. Call the provided callback + * on each device found. + */ +static void pci_walk_bridge(struct pci_dev *bridge, + int (*cb)(struct pci_dev *, void *), + void *userdata) +{ + if (bridge->subordinate) + pci_walk_bus(bridge->subordinate, cb, userdata); +} + pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, pci_channel_state_t state, pci_ers_result_t (*reset_subordinates)(struct pci_dev *pdev)) { int type = pci_pcie_type(dev); struct pci_dev *bridge; - struct pci_bus *bus; pci_ers_result_t status = PCI_ERS_RESULT_CAN_RECOVER;
/* @@ -165,23 +182,22 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, else bridge = pci_upstream_bridge(dev);
- bus = bridge->subordinate; pci_dbg(bridge, "broadcast error_detected message\n"); if (state == pci_channel_io_frozen) { - pci_walk_bus(bus, report_frozen_detected, &status); + pci_walk_bridge(bridge, report_frozen_detected, &status); status = reset_subordinates(bridge); if (status != PCI_ERS_RESULT_RECOVERED) { pci_warn(bridge, "subordinate device reset failed\n"); goto failed; } } else { - pci_walk_bus(bus, report_normal_detected, &status); + pci_walk_bridge(bridge, report_normal_detected, &status); }
if (status == PCI_ERS_RESULT_CAN_RECOVER) { status = PCI_ERS_RESULT_RECOVERED; pci_dbg(bridge, "broadcast mmio_enabled message\n"); - pci_walk_bus(bus, report_mmio_enabled, &status); + pci_walk_bridge(bridge, report_mmio_enabled, &status); }
if (status == PCI_ERS_RESULT_NEED_RESET) { @@ -192,14 +208,14 @@ pci_ers_result_t pcie_do_recovery(struct pci_dev *dev, */ status = PCI_ERS_RESULT_RECOVERED; pci_dbg(bridge, "broadcast slot_reset message\n"); - pci_walk_bus(bus, report_slot_reset, &status); + pci_walk_bridge(bridge, report_slot_reset, &status); }
if (status != PCI_ERS_RESULT_RECOVERED) goto failed;
pci_dbg(bridge, "broadcast resume message\n"); - pci_walk_bus(bus, report_resume, &status); + pci_walk_bridge(bridge, report_resume, &status);
if (pcie_aer_is_native(bridge)) pcie_clear_device_status(bridge);