[PATCH v19 3/4] PCI: Fail FLR when config space is inaccessible

[Farhan Ali <alifm@linux.ibm.com>]

If a device is in an error state, then it's config space may not be
accssible. Add additional check to validate if a device's config space is
accessible before doing an FLR reset.

Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Niklas Schnelle <schnelle@linux.ibm.com>
Signed-off-by: Farhan Ali <alifm@linux.ibm.com>
---
 drivers/pci/pci.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 973d23e41c48..521a4bb189d7 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4352,6 +4352,9 @@ int pcie_flr(struct pci_dev *dev)
 {
 	int ret;
 
+	if (!pci_dev_config_accessible(dev, "FLR"))
+		return -ENOTTY;
+
 	if (!pci_wait_for_pending_transaction(dev))
 		pci_err(dev, "timed out waiting for pending transaction; performing function level reset anyway\n");
 
-- 
2.43.0