@@ -371,17 +371,14 @@ static inline bool pci_dev_set_io_state(struct pci_dev *dev,
* perm_failure | perm_failure* perm_failure* perm_failure
*/
- /* Can always put a device in perm_failure state */
- if (new == pci_channel_io_perm_failure) {
- dev->error_state = pci_channel_io_perm_failure;
- return true;
- }
-
- /* If already in perm_failure, can't set to normal or frozen */
+ /* If already in perm_failure, can't change it's state */
if (dev->error_state == pci_channel_io_perm_failure)
return false;
+ /* not change at all */
+ else if (dev->error_state == new)
+ return false;
- /* Can always change normal to frozen or vice versa */
+ /* Can always change from normal/frozen to other different state */
dev->error_state = new;
return true;
}
When uncorrectable error happens, AER driver and DPC driver interrupt handlers likely call pcie_do_recovery() ->pci_walk_bus() ->report_frozen_detected() with pci_channel_io_frozen the same time. If pci_dev_set_io_state() return true even if the original state is pci_channel_io_frozen, that will cause AER or DPC handler re-enter the error detecting and recovery procedure one after another. The result is the recovery flow mixed between AER and DPC. So change the pci_dev_set_io_state() function to only return true when dev->error_state is really changed. Signed-off-by: Ethan Zhao <haifeng.zhao@intel.com> --- Changnes: v2: revise description and code according to suggestion from Andy. v3: change code to simpler. v4: no change. v5: no change. v6: no change. v7: changed based on Bjorn's code and truth table. v8: according to Bjorn's suggestion, rebase on another simplification patch. drivers/pci/pci.h | 13 +++++-------- 1 file changed, 5 insertions(+), 8 deletions(-)