4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Vaibhav Jain <vaibhav@xxxxxxxxxxxxxxxxxx>
commit 4f58f0bf155e87dda31a3088b1e107fa9dd79f0e upstream.
Fix a boundary condition where in some cases an eeh event that results
in card reset isn't passed on to a driver attached to the virtual PCI
device associated with a slice. This will happen in case when a slice
attached device driver returns a value other than
PCI_ERS_RESULT_NEED_RESET from the eeh error_detected() callback. This
would result in an early return from cxl_pci_error_detected() and
other drivers attached to other AFUs on the card wont be notified.
The patch fixes this by making sure that all slice attached
device-drivers are notified and the return values from
error_detected() callback are aggregated in a scheme where request for
'disconnect' trumps all and 'none' trumps 'need_reset'.
Fixes: 9e8df8a21963 ("cxl: EEH support")
Signed-off-by: Vaibhav Jain <vaibhav@xxxxxxxxxxxxxxxxxx>
Reviewed-by: Andrew Donnellan <andrew.donnellan@xxxxxxxxxxx>
Acked-by: Frederic Barrat <fbarrat@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/misc/cxl/pci.c | 15 +++++++++------
1 file changed, 9 insertions(+), 6 deletions(-)
--- a/drivers/misc/cxl/pci.c
+++ b/drivers/misc/cxl/pci.c
@@ -1779,7 +1779,7 @@ static pci_ers_result_t cxl_pci_error_de
{
struct cxl *adapter = pci_get_drvdata(pdev);
struct cxl_afu *afu;
- pci_ers_result_t result = PCI_ERS_RESULT_NEED_RESET;
+ pci_ers_result_t result = PCI_ERS_RESULT_NEED_RESET, afu_result;
int i;
/* At this point, we could still have an interrupt pending.
@@ -1884,15 +1884,18 @@ static pci_ers_result_t cxl_pci_error_de
for (i = 0; i < adapter->slices; i++) {
afu = adapter->afu[i];
- result = cxl_vphb_error_detected(afu, state);
-
- /* Only continue if everyone agrees on NEED_RESET */
- if (result != PCI_ERS_RESULT_NEED_RESET)
- return result;
+ afu_result = cxl_vphb_error_detected(afu, state);
cxl_context_detach_all(afu);
cxl_ops->afu_deactivate_mode(afu, afu->current_mode);
pci_deconfigure_afu(afu);
+
+ /* Disconnect trumps all, NONE trumps NEED_RESET */
+ if (afu_result == PCI_ERS_RESULT_DISCONNECT)
+ result = PCI_ERS_RESULT_DISCONNECT;
+ else if ((afu_result == PCI_ERS_RESULT_NONE) &&
+ (result == PCI_ERS_RESULT_NEED_RESET))
+ result = PCI_ERS_RESULT_NONE;
}
/* should take the context lock here */