platform/x86/intel/vsec: Fix enable_cnt imbalance on PCIe error recovery

After a PCIe Uncorrectable Error has been reported by a device with
Intel Vendor Specific Extended Capabilities and has been recovered
through a Secondary Bus Reset, its driver calls intel_vsec_pci_probe()
to rescan and reinitialize VSECs.

intel_vsec_pci_probe() invokes pcim_enable_device() and thereby adds
another devm action which calls pcim_disable_device() on driver unbind.

So once the driver unbinds, pcim_disable_device() will be called as many
times as an Uncorrectable Error occurred, plus one.  This will lead to
an enable_cnt imbalance on driver unbind.

Additionally, since commit dc957ab ("platform/x86/intel/vsec: Add
private data for per-device data"), a devm_kzalloc() allocation is
leaked on every Uncorrectable Error.

Avoid by splitting the VSEC rescan out of intel_vsec_pci_probe() into a
separate helper and calling that on PCIe error recovery.

Fixes: 936874b ("platform/x86/intel/vsec: Add PCI error recovery support to Intel PMT")
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: stable@vger.kernel.org  # v6.0+
Link: https://patch.msgid.link/bd594d09fa866dc51dddc9a447c3b23f9b1402cc.1778736835.git.lukas@wunner.de
Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>

Author: l1k

drivers/platform/x86/intel/vsec.c

@@ -649,29 +649,13 @@ static void intel_vsec_skip_missing_dependencies(struct pci_dev *pdev)
 	}
 }
 
-static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+static int intel_vsec_pci_init(struct pci_dev *pdev)
 {
-	const struct intel_vsec_platform_info *info;
-	struct vsec_priv *priv;
-	int num_caps, ret;
+	struct vsec_priv *priv = pci_get_drvdata(pdev);
+	const struct intel_vsec_platform_info *info = priv->info;
 	int run_once = 0;
 	bool found_any = false;
-
-	ret = pcim_enable_device(pdev);
-	if (ret)
-		return ret;
-
-	pci_save_state(pdev);
-	info = (const struct intel_vsec_platform_info *)id->driver_data;
-	if (!info)
-		return -EINVAL;
-
-	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
-	if (!priv)
-		return -ENOMEM;
-
-	priv->info = info;
-	pci_set_drvdata(pdev, priv);
+	int num_caps;
 
 	num_caps = hweight_long(info->caps);
 	while (num_caps--) {
@@ -692,6 +676,31 @@ static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id
 	return 0;
 }
 
+static int intel_vsec_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id)
+{
+	const struct intel_vsec_platform_info *info;
+	struct vsec_priv *priv;
+	int ret;
+
+	ret = pcim_enable_device(pdev);
+	if (ret)
+		return ret;
+
+	pci_save_state(pdev);
+	info = (const struct intel_vsec_platform_info *)id->driver_data;
+	if (!info)
+		return -EINVAL;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->info = info;
+	pci_set_drvdata(pdev, priv);
+
+	return intel_vsec_pci_init(pdev);
+}
+
 int intel_vsec_set_mapping(struct oobmsm_plat_info *plat_info,
 			   struct intel_vsec_device *vsec_dev)
 {
@@ -832,7 +841,6 @@ static pci_ers_result_t intel_vsec_pci_slot_reset(struct pci_dev *pdev)
 {
 	struct intel_vsec_device *intel_vsec_dev;
 	pci_ers_result_t status = PCI_ERS_RESULT_DISCONNECT;
-	const struct pci_device_id *pci_dev_id;
 	unsigned long index;
 
 	dev_info(&pdev->dev, "Resetting PCI slot\n");
@@ -853,10 +861,8 @@ static pci_ers_result_t intel_vsec_pci_slot_reset(struct pci_dev *pdev)
 		devm_release_action(&pdev->dev, intel_vsec_remove_aux,
 				    &intel_vsec_dev->auxdev);
 	}
-	pci_disable_device(pdev);
 	pci_restore_state(pdev);
-	pci_dev_id = pci_match_id(intel_vsec_pci_ids, pdev);
-	intel_vsec_pci_probe(pdev, pci_dev_id);
+	intel_vsec_pci_init(pdev);
 
 out:
 	return status;