ACPI: WMI: Survive BIOS with duplicate GUIDs
It would appear that in BIOS's with nVidia hooks, the GUID
05901221-D566-11D1-B2F0-00A0C9062910 is duplicated. For now, the simplest
solution is to just ignore any duplicate GUIDs. These particular hooks are not
currently supported/ used in the kernel, so whoever does that can figure out
what the 'right' solution should be (if there's a better one).
http://bugzilla.kernel.org/show_bug.cgi?id=14846
Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk>
Reported-by: Larry Finger <Larry.Finger@lwfinger.net>
Reported-by: Oldřich Jedlička <oldium.pro@seznam.cz>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/drivers/platform/x86/wmi.c b/drivers/platform/x86/wmi.c
index cc9ad74..b104302 100644
--- a/drivers/platform/x86/wmi.c
+++ b/drivers/platform/x86/wmi.c
@@ -714,6 +714,22 @@
return ret;
}
+static bool guid_already_parsed(const char *guid_string)
+{
+ struct guid_block *gblock;
+ struct wmi_block *wblock;
+ struct list_head *p;
+
+ list_for_each(p, &wmi_blocks.list) {
+ wblock = list_entry(p, struct wmi_block, list);
+ gblock = &wblock->gblock;
+
+ if (strncmp(gblock->guid, guid_string, 16) == 0)
+ return true;
+ }
+ return false;
+}
+
/*
* Parse the _WDG method for the GUID data blocks
*/
@@ -723,6 +739,7 @@
union acpi_object *obj;
struct guid_block *gblock;
struct wmi_block *wblock;
+ char guid_string[37];
acpi_status status;
u32 i, total;
@@ -745,6 +762,19 @@
memcpy(gblock, obj->buffer.pointer, obj->buffer.length);
for (i = 0; i < total; i++) {
+ /*
+ Some WMI devices, like those for nVidia hooks, have a
+ duplicate GUID. It's not clear what we should do in this
+ case yet, so for now, we'll just ignore the duplicate.
+ Anyone who wants to add support for that device can come
+ up with a better workaround for the mess then.
+ */
+ if (guid_already_parsed(gblock[i].guid) == true) {
+ wmi_gtoa(gblock[i].guid, guid_string);
+ printk(KERN_INFO PREFIX "Skipping duplicate GUID %s\n",
+ guid_string);
+ continue;
+ }
wblock = kzalloc(sizeof(struct wmi_block), GFP_KERNEL);
if (!wblock)
return AE_NO_MEMORY;