powerpc/eeh: Don't collect PCI-CFG data on PHB
When the PHB is fenced or dead, it's pointless to collect the data
from PCI config space of subordinate PCI devices since it should
return 0xFF's. The patch also fixes overwritten buffer while getting
PCI config data.
Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/kernel/eeh.c b/arch/powerpc/kernel/eeh.c
index e579652..416fb43 100644
--- a/arch/powerpc/kernel/eeh.c
+++ b/arch/powerpc/kernel/eeh.c
@@ -232,16 +232,30 @@
{
size_t loglen = 0;
struct eeh_dev *edev;
+ bool valid_cfg_log = true;
- eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
- eeh_ops->configure_bridge(pe);
- eeh_pe_restore_bars(pe);
+ /*
+ * When the PHB is fenced or dead, it's pointless to collect
+ * the data from PCI config space because it should return
+ * 0xFF's. For ER, we still retrieve the data from the PCI
+ * config space.
+ */
+ if (eeh_probe_mode_dev() &&
+ (pe->type & EEH_PE_PHB) &&
+ (pe->state & (EEH_PE_ISOLATED | EEH_PE_PHB_DEAD)))
+ valid_cfg_log = false;
- pci_regs_buf[0] = 0;
- eeh_pe_for_each_dev(pe, edev) {
- loglen += eeh_gather_pci_data(edev, pci_regs_buf,
- EEH_PCI_REGS_LOG_LEN);
- }
+ if (valid_cfg_log) {
+ eeh_pci_enable(pe, EEH_OPT_THAW_MMIO);
+ eeh_ops->configure_bridge(pe);
+ eeh_pe_restore_bars(pe);
+
+ pci_regs_buf[0] = 0;
+ eeh_pe_for_each_dev(pe, edev) {
+ loglen += eeh_gather_pci_data(edev, pci_regs_buf + loglen,
+ EEH_PCI_REGS_LOG_LEN - loglen);
+ }
+ }
eeh_ops->get_log(pe, severity, pci_regs_buf, loglen);
}