From d1f9e4970742bb1e22d07b01bd44f9c357d25c42 Mon Sep 17 00:00:00 2001 From: Carlos Corbacho Date: Sat, 26 Dec 2009 19:14:59 +0000 Subject: [PATCH] ACPI: WMI: Survive BIOS with duplicate GUIDs MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit 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 Reported-by: Larry Finger Reported-by: Oldřich Jedlička Signed-off-by: Len Brown --- drivers/platform/x86/wmi.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) 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 @@ static int wmi_class_init(void) 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 @@ static __init acpi_status parse_wdg(acpi_handle handle) 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 @@ static __init acpi_status parse_wdg(acpi_handle handle) 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; -- 2.7.4