PCI: Avoid FLR for Intel 82579 NICs
Per Intel Specification Update 335553-002 (see link below), some 82579
network adapters advertise a Function Level Reset (FLR) capability, but
they can hang when an FLR is triggered.
To reproduce the problem, attach the device to a VM, then detach and try to
attach again.
Add a quirk to prevent the use of FLR on these devices.
[bhelgaas: changelog, comments]
Link: http://www.intel.com/content/dam/www/public/us/en/documents/specification-updates/82579lm-82579v-gigabit-network-connection-spec-update.pdf
Signed-off-by: Sasha Neftin <sasha.neftin@intel.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 7904d02..bef1477 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3781,6 +3781,9 @@
if (!(cap & PCI_EXP_DEVCAP_FLR))
return -ENOTTY;
+ if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)
+ return -ENOTTY;
+
if (probe)
return 0;
@@ -3801,6 +3804,9 @@
if (!pos)
return -ENOTTY;
+ if (dev->dev_flags & PCI_DEV_FLAGS_NO_FLR_RESET)
+ return -ENOTTY;
+
pci_read_config_byte(dev, pos + PCI_AF_CAP, &cap);
if (!(cap & PCI_AF_CAP_TP) || !(cap & PCI_AF_CAP_FLR))
return -ENOTTY;