After a PCIe Uncorrectable Error has been reported by an i40e adapter
and has been recovered through a Secondary Bus Reset, its driver calls
pci_enable_device() without having called pci_disable_device().
This leads to an imbalance of the enable_cnt tracked by the PCI core:
Every time error recovery occurs, the enable_cnt keeps growing. If it
occurs at least once and the driver is then unbound, the device isn't
disabled since the enable_cnt hasn't reached zero (and never again will).
The call to pci_enable_device() has almost no effect because the
enable_cnt was already incremented in i40e_probe() through the call to
pci_enable_device_mem(). The subsequent pci_enable_device() thus bails
out after invoking pci_update_current_state().
Remove pci_enable_device(). In lieu of pci_update_current_state(), set
the power state to D0 because that's the power state after a Secondary
Bus Reset (PCIe r7.0 sec 5.3.1.1).
The intended purpose of pci_enable_device() may have been to set the
Memory Space Enable bit in the Command register again after reset, but
that is already achieved by the subsequent call to pci_restore_state().
Fixes: 41c445ff0f48 ("i40e: main driver core")
Signed-off-by: Lukas Wunner <[email protected]>
Cc: [email protected] # v3.12+
---
drivers/net/ethernet/intel/i40e/i40e_main.c | 29 +++++++--------------
1 file changed, 10 insertions(+), 19 deletions(-)
diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c
b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 9d6d892602fa..7e87234fde67 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -16439,29 +16439,20 @@ static pci_ers_result_t
i40e_pci_error_detected(struct pci_dev *pdev,
static pci_ers_result_t i40e_pci_error_slot_reset(struct pci_dev *pdev)
{
struct i40e_pf *pf = pci_get_drvdata(pdev);
- pci_ers_result_t result;
u32 reg;
dev_dbg(&pdev->dev, "%s\n", __func__);
- /* enable I/O and memory of the device */
- if (pci_enable_device(pdev)) {
- dev_info(&pdev->dev,
- "Cannot re-enable PCI device after reset.\n");
- result = PCI_ERS_RESULT_DISCONNECT;
- } else {
- pci_set_master(pdev);
- pci_restore_state(pdev);
- pci_save_state(pdev);
- pci_wake_from_d3(pdev, false);
-
- reg = rd32(&pf->hw, I40E_GLGEN_RTRIG);
- if (reg == 0)
- result = PCI_ERS_RESULT_RECOVERED;
- else
- result = PCI_ERS_RESULT_DISCONNECT;
- }
+ pdev->current_state = PCI_D0;
+ pci_set_master(pdev);
+ pci_restore_state(pdev);
+ pci_save_state(pdev);
+ pci_wake_from_d3(pdev, false);
- return result;
+ reg = rd32(&pf->hw, I40E_GLGEN_RTRIG);
+ if (reg == 0)
+ return PCI_ERS_RESULT_RECOVERED;
+ else
+ return PCI_ERS_RESULT_DISCONNECT;
}
/**
--
2.47.2
