[PATCH] ACPI: Provide an OSI interface not returning true for Windows to the BIOS

[PATCH] ACPI: Provide an OSI interface not returning true for Windows to the BIOS

[Thomas Renninger]

Compile tested only.
No functional change without explicitly setting a boot param or a .config 
option.
---

ACPI: Provide a spec conform OSI interface not returning true for Windows to 
the BIOS

Introduce acpi_osi=windows_false boot parameter
Introduce CONFIG_ACPI_OSI_SPEC_CONFORM config option

This will return false to _OSI("Windows XY") calls.

Signed-off-by: Thomas Renninger <trenn@suse.de>
---
 Documentation/kernel-parameters.txt |    1 +
 drivers/acpi/Kconfig                |   12 ++++++++++++
 drivers/acpi/osl.c                  |   28 ++++++++++++++++++++++------
 3 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/Documentation/kernel-parameters.txt 
b/Documentation/kernel-parameters.txt
index c657339..6acfe8e 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -178,6 +178,7 @@ and is between 256 and 4096 characters. It is defined in 
the file
 	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="windows_false"# remove all Windows strings
 			acpi_osi=		# disable all strings
 
 	acpi_serialize	[HW,ACPI] force serialization of AML methods
diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
index c52fca8..5fac9c9 100644
--- a/drivers/acpi/Kconfig
+++ b/drivers/acpi/Kconfig
@@ -314,6 +314,18 @@ config ACPI_BLACKLIST_YEAR
 	  Enter 0 to disable this mechanism and allow ACPI to
 	  run by default no matter what the year.  (default)
 
+config ACPI_OSI_WINDOWS_FALSE
+	bool "Return false for Window strings for OSI(\"string\") BIOS calls"
+	default n
+	help
+	  By default Linux tries to stay transparent to Windows OSes to the
+	  BIOS and returns true for all currently known Windows OS strings and
+	  false for Linux.
+	  With this option set, OSI will return false for Windows strings.
+	  The kernel will still return false for _OSI("Linux") BIOS calls
+	  by default, but eventually return true for _OSI("Linux"), depending
+	  on a blacklist.
+
 config ACPI_DEBUG
 	bool "Debug Statements"
 	default n
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 235a138..bf951f6 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -194,11 +194,6 @@ static int __init acpi_reserve_resources(void)
 }
 device_initcall(acpi_reserve_resources);
 
-acpi_status __init acpi_os_initialize(void)
-{
-	return AE_OK;
-}
-
 acpi_status acpi_os_initialize1(void)
 {
 	kacpid_wq = create_singlethread_workqueue("kacpid");
@@ -943,7 +938,7 @@ static void __init set_osi_linux(unsigned int enable)
 	if (osi_linux.enable != enable) {
 		osi_linux.enable = enable;
 		printk(KERN_NOTICE PREFIX "%sed _OSI(Linux)\n",
-			enable ? "Add": "Delet");
+			enable ? "Add": "Delete");
 	}
 	return;
 }
@@ -972,6 +967,25 @@ void __init acpi_dmi_osi_linux(int enable, const struct 
dmi_system_id *d)
 	return;
 }
 
+static void __init acpi_osi_windows_false(void) {
+
+	acpi_osi_invalidate("Windows 2000");
+	acpi_osi_invalidate("Windows 2001");
+	acpi_osi_invalidate("Windows 2001 SP1");
+	acpi_osi_invalidate("Windows 2001 SP2");
+	acpi_osi_invalidate("Windows 2001.1");
+	acpi_osi_invalidate("Windows 2001.1 SP1");
+	acpi_osi_invalidate("Windows 2006");
+}
+
+acpi_status __init acpi_os_initialize(void)
+{
+#ifdef CONFIG_ACPI_OSI_WINDOWS_FALSE
+	acpi_osi_windows_false();
+#endif
+	return AE_OK;
+}
+
 /*
  * Modify the list of "OS Interfaces" reported to BIOS via _OSI
  *
@@ -984,6 +998,8 @@ int __init acpi_osi_setup(char *str)
 	if (str == NULL || *str == '\0') {
 		printk(KERN_INFO PREFIX "_OSI method disabled\n");
 		acpi_gbl_create_osi_method = FALSE;
+	} else if (strcmp("windows_false", str)) {
+		acpi_osi_windows_false();
 	} else if (!strcmp("!Linux", str)) {
 		acpi_cmdline_osi_linux(0);	/* !enable */
 	} else if (*str == '!') {
-- 
1.5.4.5

Re: [PATCH] ACPI: Provide an OSI interface not returning true for Windows to the BIOS

[Thomas Renninger]

> ACPI: Provide a spec conform OSI interface not returning true for Windows
spec conform would be to return true for Linux, this is not the case. Subject 
should be the same as in the mail subject:
ACPI: Provide an OSI interface not returning true for Windows to the BIOS