securemsm-kernel: Create device node of smcinvoke later

Because the device node of smcinvoke is published at the
beginning of the smcinvoke_probe(), the device node will
be ready while the smcinvoke is not initialized completely.
Hence the smcinvoke_release probably is called when the
smcinvoke driver is not ready. this case will lead to
smcinvoke crash issue.

To avoid this concurrency issue, we create the device node
at the end of the smcinvoke_probe.

Change-Id: I930685a24fb744893017c90c1881f13e2f2c3d7c
Signed-off-by: wenji <[email protected]>

smcinvoke/smcinvoke.c

@@ -313,8 +313,8 @@ struct smcinvoke_worker_thread {
 	struct task_struct *postprocess_kthread_task;
 };
 
-struct smcinvoke_worker_thread smcinvoke[MAX_THREAD_NUMBER];
-const char thread_name[MAX_THREAD_NUMBER][MAX_CHAR_NAME] = {
+static struct smcinvoke_worker_thread smcinvoke[MAX_THREAD_NUMBER];
+static const char thread_name[MAX_THREAD_NUMBER][MAX_CHAR_NAME] = {
 	"smcinvoke_shmbridge_postprocess", "smcinvoke_object_postprocess"};
 
 static int prepare_send_scm_msg(const uint8_t *in_buf, phys_addr_t in_paddr,
@@ -2661,11 +2661,26 @@ static int smcinvoke_probe(struct platform_device *pdev)
 	unsigned int count = 1;
 	int rc = 0;
 
+	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
+	if (rc) {
+		pr_err("dma_set_mask_and_coherent failed %d\n", rc);
+		return rc;
+	}
+	legacy_smc_call = of_property_read_bool((&pdev->dev)->of_node,
+			"qcom,support-legacy_smc");
+	invoke_cmd = legacy_smc_call ? SMCINVOKE_INVOKE_CMD_LEGACY : SMCINVOKE_INVOKE_CMD;
+
+	rc = smcinvoke_create_kthreads();
+	if (rc) {
+		pr_err("smcinvoke_create_kthreads failed %d\n", rc);
+		return rc;
+	}
+
 	rc = alloc_chrdev_region(&smcinvoke_device_no, baseminor, count,
 							SMCINVOKE_DEV);
 	if (rc < 0) {
 		pr_err("chrdev_region failed %d for %s\n", rc, SMCINVOKE_DEV);
-		return rc;
+		goto exit_destroy_wkthread;
 	}
 	driver_class = class_create(THIS_MODULE, SMCINVOKE_DEV);
 	if (IS_ERR(driver_class)) {
@@ -2691,31 +2706,17 @@ static int smcinvoke_probe(struct platform_device *pdev)
 		goto exit_destroy_device;
 	}
 	smcinvoke_pdev = pdev;
-	rc = dma_set_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(64));
-	if (rc) {
-		pr_err("dma_set_mask_and_coherent failed %d\n", rc);
-		goto exit_cv_del;
-	}
-	legacy_smc_call = of_property_read_bool((&pdev->dev)->of_node,
-			"qcom,support-legacy_smc");
-	invoke_cmd = legacy_smc_call ? SMCINVOKE_INVOKE_CMD_LEGACY : SMCINVOKE_INVOKE_CMD;
-
-	rc = smcinvoke_create_kthreads();
-	if (rc) {
-		pr_err("smcinvoke_create_kthreads failed %d\n", rc);
-		goto exit_cv_del;
-	}
 
 	return 0;
 
-exit_cv_del:
-	cdev_del(&smcinvoke_cdev);
 exit_destroy_device:
 	device_destroy(driver_class, smcinvoke_device_no);
 exit_destroy_class:
 	class_destroy(driver_class);
 exit_unreg_chrdev_region:
 	unregister_chrdev_region(smcinvoke_device_no, count);
+exit_destroy_wkthread:
+	smcinvoke_destroy_kthreads();
 	return rc;
 }