diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 15356aca938c..d0d9cf278ae3 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -235,10 +235,35 @@ bytes respectively. Such letter suffixes can also be entirely omitted.
 			Format: To spoof as Windows 98: ="Microsoft Windows"
 
 	acpi_osi=	[HW,ACPI] Modify list of supported OS interface strings
-			acpi_osi="string1"	# add string1 -- only one string
-			acpi_osi="!string2"	# remove built-in string2
+			acpi_osi="string1"	# add string1
+			acpi_osi="!string2"	# remove string2
+			acpi_osi=!		# disable all built-in OS vendor
+						  strings
 			acpi_osi=		# disable all strings
 
+			'acpi_osi=!' can be used in combination with single or
+			multiple 'acpi_osi="string1"' to support specific OS
+			vendor string(s).  Note that such command can only
+			affect the default state of the OS vendor strings, thus
+			it cannot affect the default state of the feature group
+			strings and the current state of the OS vendor strings,
+			specifying it multiple times through kernel command line
+			is meaningless.
+			Examples:
+			  1. 'acpi_osi=! acpi_osi="Windows 2000"' is equivalent
+			     to 'acpi_osi="Windows 2000" acpi_osi=!', they all
+			     can make '_OSI("Windows 2000")' TRUE.
+
+			'acpi_osi=' cannot be used in combination with other
+			'acpi_osi=' command lines, the _OSI method will not
+			exist in the ACPI namespace.  NOTE that such command can
+			only affect the _OSI support state, thus specifying it
+			multiple times through kernel command line is also
+			meaningless.
+			Examples:
+			  1. 'acpi_osi=' can make 'CondRefOf(_OSI, Local1)'
+			     FALSE.
+
 	acpi_pm_good	[X86]
 			Override the pmtimer bug detection: force the kernel
 			to assume that this machine's pmtimer latches its value
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 6ab2c3505520..e8baa408faef 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -140,7 +140,8 @@ static struct osi_linux {
 	unsigned int	enable:1;
 	unsigned int	dmi:1;
 	unsigned int	cmdline:1;
-} osi_linux = {0, 0, 0};
+	unsigned int	default_disabling:1;
+} osi_linux = {0, 0, 0, 0};
 
 static u32 acpi_osi_handler(acpi_string interface, u32 supported)
 {
@@ -1376,6 +1377,10 @@ void __init acpi_osi_setup(char *str)
 
 	if (*str == '!') {
 		str++;
+		if (*str == '\0') {
+			osi_linux.default_disabling = 1;
+			return;
+		}
 		enable = false;
 	}
 
@@ -1441,6 +1446,13 @@ static void __init acpi_osi_setup_late(void)
 	int i;
 	acpi_status status;
 
+	if (osi_linux.default_disabling) {
+		status = acpi_update_interfaces(ACPI_DISABLE_ALL_VENDOR_STRINGS);
+
+		if (ACPI_SUCCESS(status))
+			printk(KERN_INFO PREFIX "Disabled all _OSI OS vendors\n");
+	}
+
 	for (i = 0; i < OSI_STRING_ENTRIES_MAX; i++) {
 		osi = &osi_setup_entries[i];
 		str = osi->string;