ACPI / einj: Make error paths more talkative

It is absolutely unfriendly when one sees this:

  # modprobe einj
  modprobe: ERROR: could not insert 'einj': No such device

without anything in dmesg to tell one why the load failed.

Beef up the error handling of the init function to be more user-friendly
when the load fails.

Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

diff --git a/drivers/acpi/apei/einj.c b/drivers/acpi/apei/einj.c
index 4ba4185..eebb7e3 100644 (file)
--- a/drivers/acpi/apei/einj.c
+++ b/drivers/acpi/apei/einj.c
@@ -692,34 +692,42 @@ static int __init einj_init(void)
        struct dentry *fentry;
        struct apei_exec_context ctx;
 
-       if (acpi_disabled)
+       if (acpi_disabled) {
+               pr_warn("ACPI disabled.\n");
                return -ENODEV;
+       }
 
        status = acpi_get_table(ACPI_SIG_EINJ, 0,
                                (struct acpi_table_header **)&einj_tab);
-       if (status == AE_NOT_FOUND)
+       if (status == AE_NOT_FOUND) {
+               pr_warn("EINJ table not found.\n");
                return -ENODEV;
+       }
        else if (ACPI_FAILURE(status)) {
-               const char *msg = acpi_format_exception(status);
-               pr_err("Failed to get table, %s\n", msg);
+               pr_err("Failed to get EINJ table: %s\n",
+                               acpi_format_exception(status));
                return -EINVAL;
        }
 
        rc = einj_check_table(einj_tab);
        if (rc) {
-               pr_warning(FW_BUG "EINJ table is invalid\n");
+               pr_warn(FW_BUG "Invalid EINJ table.n");
                return -EINVAL;
        }
 
        rc = -ENOMEM;
        einj_debug_dir = debugfs_create_dir("einj", apei_get_debugfs_dir());
-       if (!einj_debug_dir)
+       if (!einj_debug_dir) {
+               pr_err("Error creating debugfs node.\n");
                goto err_cleanup;
+       }
+
        fentry = debugfs_create_file("available_error_type", S_IRUSR,
                                     einj_debug_dir, NULL,
                                     &available_error_type_fops);
        if (!fentry)
                goto err_cleanup;
+
        fentry = debugfs_create_file("error_type", S_IRUSR | S_IWUSR,
                                     einj_debug_dir, NULL, &error_type_fops);
        if (!fentry)
@@ -732,14 +740,22 @@ static int __init einj_init(void)
        apei_resources_init(&einj_resources);
        einj_exec_ctx_init(&ctx);
        rc = apei_exec_collect_resources(&ctx, &einj_resources);
-       if (rc)
+       if (rc) {
+               pr_err("Error collecting EINJ resources.\n");
                goto err_fini;
+       }
+
        rc = apei_resources_request(&einj_resources, "APEI EINJ");
-       if (rc)
+       if (rc) {
+               pr_err("Error requesting memory/port resources.\n");
                goto err_fini;
+       }
+
        rc = apei_exec_pre_map_gars(&ctx);
-       if (rc)
+       if (rc) {
+               pr_err("Error pre-mapping GARs.\n");
                goto err_release;
+       }
 
        rc = -ENOMEM;
        einj_param = einj_get_parameter_address();
@@ -795,6 +811,7 @@ err_unmap:
                        sizeof(struct einj_parameter);
 
                acpi_os_unmap_iomem(einj_param, size);
+               pr_err("Error creating param extension debugfs nodes.\n");
        }
        apei_exec_post_unmap_gars(&ctx);
 err_release:
@@ -802,6 +819,7 @@ err_release:
 err_fini:
        apei_resources_fini(&einj_resources);
 err_cleanup:
+       pr_err("Error creating primary debugfs nodes.\n");
        debugfs_remove_recursive(einj_debug_dir);
 
        return rc;