PCI: Check for PCI_HEADER_TYPE_BRIDGE equality, not bitmask

Bit 7 of the "Header Type" register indicates a multi-function device when
set.  Bits 0-6 contain encoded values, where 0x1 indicates a PCI-PCI
bridge.  It is incorrect to test this as though it were a mask.

For example, while the PCI 3.0 spec only defines values 0x0, 0x1, and 0x2,
it's conceivable that a future spec could define 0x3 to mean something
else; then tests for "(hdr_type & 0x7f) & PCI_HEADER_TYPE_BRIDGE" would
incorrectly succeed for this new 0x3 header type.

Test bits 0-6 of the Header Type for equality with PCI_HEADER_TYPE_BRIDGE.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
This commit is contained in:
Bjorn Helgaas 2015-12-03 13:18:18 -06:00
parent 1ec218373b
commit 93de690176
3 changed files with 7 additions and 7 deletions

View File

@ -400,7 +400,7 @@ static void *eeh_rmv_device(void *data, void *userdata)
* support EEH. So we just care about PCI devices for
* simplicity here.
*/
if (!dev || (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE))
if (!dev || (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE))
return NULL;
/*

View File

@ -1119,7 +1119,7 @@ static struct res_needed *scan_behind_bridge (struct pci_func *func, u8 busno)
pci_bus_read_config_dword (ibmphp_pci_bus, devfn, PCI_CLASS_REVISION, &class);
debug ("hdr_type behind the bridge is %x\n", hdr_type);
if (hdr_type & PCI_HEADER_TYPE_BRIDGE) {
if ((hdr_type & 0x7f) == PCI_HEADER_TYPE_BRIDGE) {
err ("embedded bridges not supported for hot-plugging.\n");
amount->not_correct = 1;
return amount;

View File

@ -246,7 +246,7 @@ static int report_error_detected(struct pci_dev *dev, void *data)
!dev->driver->err_handler ||
!dev->driver->err_handler->error_detected) {
if (result_data->state == pci_channel_io_frozen &&
!(dev->hdr_type & PCI_HEADER_TYPE_BRIDGE)) {
dev->hdr_type != PCI_HEADER_TYPE_BRIDGE) {
/*
* In case of fatal recovery, if one of down-
* stream device has no driver. We might be
@ -269,7 +269,7 @@ static int report_error_detected(struct pci_dev *dev, void *data)
* without recovery.
*/
if (!(dev->hdr_type & PCI_HEADER_TYPE_BRIDGE))
if (dev->hdr_type != PCI_HEADER_TYPE_BRIDGE)
vote = PCI_ERS_RESULT_NO_AER_DRIVER;
else
vote = PCI_ERS_RESULT_NONE;
@ -369,7 +369,7 @@ static pci_ers_result_t broadcast_error_message(struct pci_dev *dev,
else
result_data.result = PCI_ERS_RESULT_RECOVERED;
if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) {
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
/*
* If the error is reported by a bridge, we think this error
* is related to the downstream link of the bridge, so we
@ -440,7 +440,7 @@ static pci_ers_result_t reset_link(struct pci_dev *dev)
pci_ers_result_t status;
struct pcie_port_service_driver *driver;
if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE) {
if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE) {
/* Reset this port for all subordinates */
udev = dev;
} else {
@ -660,7 +660,7 @@ static int get_device_error_info(struct pci_dev *dev, struct aer_err_info *info)
&info->mask);
if (!(info->status & ~info->mask))
return 0;
} else if (dev->hdr_type & PCI_HEADER_TYPE_BRIDGE ||
} else if (dev->hdr_type == PCI_HEADER_TYPE_BRIDGE ||
info->severity == AER_NONFATAL) {
/* Link is still healthy for IO reads */