ACPI: thinkpad-acpi: fix the module init failure path

Thomas Renninger reports that if one tries to load thinkpad-acpi in a
non-thinkpad, one gets:

Call Trace:
 [<ffffffff802fa57d>] kref_get+0x2f/0x36
 [<ffffffff802f97f7>] kobject_get+0x12/0x17
 [<ffffffff8036dfd7>] get_driver+0x14/0x1a
 [<ffffffff8036dfee>] driver_remove_file+0x11/0x32
 [<ffffffff8823b9be>] :thinkpad_acpi:thinkpad_acpi_module_exit+0xa8/0xfc
 [<ffffffff8824b8a0>] :thinkpad_acpi:thinkpad_acpi_module_init+0x74a/0x776
 [<ffffffff8024f968>] __link_module+0x0/0x25
 [<ffffffff80252269>] sys_init_module+0x162c/0x178f
 [<ffffffff8020bc2e>] system_call+0x7e/0x83

So, track if the platform driver and its driver attributes were registered,
and only deallocate them in that case.

This patch is based on Thomas Renninger's patch for the issue.

Signed-off-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Acked-by: Thomas Renninger <trenn@suse.de>
Signed-off-by: Len Brown <len.brown@intel.com>

diff --git a/drivers/misc/thinkpad_acpi.c b/drivers/misc/thinkpad_acpi.c
index fa80f355e522ffc65f6a67caa96659e1e7f2e7d0..f6cd34a3dbaca218cf0ff8a19ff94d03c41cb8d7 100644 (file)
--- a/drivers/misc/thinkpad_acpi.c
+++ b/drivers/misc/thinkpad_acpi.c
@@ -4668,12 +4668,15 @@ static int __init thinkpad_acpi_module_init(void)
                thinkpad_acpi_module_exit();
                return ret;
        }
+       tp_features.platform_drv_registered = 1;
+
        ret = tpacpi_create_driver_attributes(&tpacpi_pdriver.driver);
        if (ret) {
                printk(IBM_ERR "unable to create sysfs driver attributes\n");
                thinkpad_acpi_module_exit();
                return ret;
        }
+       tp_features.platform_drv_attrs_registered = 1;
 
 
        /* Device initialization */
@@ -4756,8 +4759,11 @@ static void thinkpad_acpi_module_exit(void)
        if (tpacpi_pdev)
                platform_device_unregister(tpacpi_pdev);
 
-       tpacpi_remove_driver_attributes(&tpacpi_pdriver.driver);
-       platform_driver_unregister(&tpacpi_pdriver);
+       if (tp_features.platform_drv_attrs_registered)
+               tpacpi_remove_driver_attributes(&tpacpi_pdriver.driver);
+
+       if (tp_features.platform_drv_registered)
+               platform_driver_unregister(&tpacpi_pdriver);
 
        if (proc_dir)
                remove_proc_entry(IBM_PROC_DIR, acpi_root_dir);

diff --git a/drivers/misc/thinkpad_acpi.h b/drivers/misc/thinkpad_acpi.h
index 88af089d64945b41a5150e545a5064ce1b6f0a5a..eee8809a50d9aed1ed796a20fe6f4c5a6ae4ae5c 100644 (file)
--- a/drivers/misc/thinkpad_acpi.h
+++ b/drivers/misc/thinkpad_acpi.h
@@ -246,6 +246,8 @@ static struct {
        u16 wan:1;
        u16 fan_ctrl_status_undef:1;
        u16 input_device_registered:1;
+       u16 platform_drv_registered:1;
+       u16 platform_drv_attrs_registered:1;
 } tp_features;
 
 struct thinkpad_id_data {