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ACPI / osi: Fix an issue that acpi_osi=!* cannot disable ACPICA internal strings

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The order of the _OSI related functionalities is as follows:

  acpi_blacklisted()
    acpi_dmi_osi_linux()
      acpi_osi_setup()
    acpi_osi_setup()
      acpi_update_interfaces() if "!*"
      <<<<<<<<<<<<<<<<<<<<<<<<
  parse_args()
    __setup("acpi_osi=")
      acpi_osi_setup_linux()
        acpi_update_interfaces() if "!*"
        <<<<<<<<<<<<<<<<<<<<<<<<
  acpi_early_init()
    acpi_initialize_subsystem()
      acpi_ut_initialize_interfaces()
      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  acpi_bus_init()
    acpi_os_initialize1()
      acpi_install_interface_handler(acpi_osi_handler)
      acpi_osi_setup_late()
        acpi_update_interfaces() for "!"
        >>>>>>>>>>>>>>>>>>>>>>>>
  acpi_osi_handler()

Since acpi_osi_setup_linux() can override acpi_dmi_osi_linux(), the command
line setting can override the DMI detection. That's why acpi_blacklisted()
is put before __setup("acpi_osi=").

Then we can notice the following wrong invocation order. There are
acpi_update_interfaces() (marked by <<<<) calls invoked before
acpi_ut_initialize_interfaces() (marked by ^^^^). This makes it impossible
to use acpi_osi=!* correctly from OSI DMI table or from the command line.
The use of acpi_osi=!* is meant to disable both ACPICA
(acpi_gbl_supported_interfaces) and Linux specific strings
(osi_setup_entries) while the ACPICA part should have stopped working
because of the order issue.

This patch fixes this issue by moving acpi_update_interfaces() to where
it is invoked for acpi_osi=! (marked by >>>>) as this is ensured to be
invoked after acpi_ut_initialize_interfaces() (marked by ^^^^). Linux
specific strings are still handled in the original place in order to make
the following command line working: acpi_osi=!* acpi_osi="Module Device".

Note that since acpi_osi=!* is meant to further disable linux specific
string comparing to the acpi_osi=!, there is no such use case in our bug
fixing work and hence there is no one using acpi_osi=!* either from the
command line or from the DMI quirks, this issue is just a theoretical
issue.

Fixes: 741d81280a (ACPI: Add facility to remove all _OSI strings)
Cc: 3.12+ <stable@vger.kernel.org> # 3.12+
Tested-by: Lukas Wunner <lukas@wunner.de>
Tested-by: Chen Yu <yu.c.chen@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit is contained in:
Lv Zheng 2016-05-03 16:48:20 +08:00 committed by Rafael J. Wysocki
parent 04974df804
commit 30c9bb0d76
1 changed files with 11 additions and 5 deletions
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16
drivers/acpi/osl.c
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@ -135,7 +135,7 @@ static struct osi_linux {
unsigned int enable:1;
unsigned int dmi:1;
unsigned int cmdline:1;
unsigned int default_disabling:1;
u8 default_disabling;
} osi_linux = {0, 0, 0, 0};
static u32 acpi_osi_handler(acpi_string interface, u32 supported)
@ -1751,10 +1751,13 @@ void __init acpi_osi_setup(char *str)
if (*str == '!') {
str++;
if (*str == '\0') {
osi_linux.default_disabling = 1;
/* Do not override acpi_osi=!* */
if (!osi_linux.default_disabling)
osi_linux.default_disabling =
ACPI_DISABLE_ALL_VENDOR_STRINGS;
return;
} else if (*str == '*') {
acpi_update_interfaces(ACPI_DISABLE_ALL_STRINGS);
osi_linux.default_disabling = ACPI_DISABLE_ALL_STRINGS;
for (i = 0; i < OSI_STRING_ENTRIES_MAX; i++) {
osi = &osi_setup_entries[i];
osi->enable = false;
@ -1827,10 +1830,13 @@ static void __init acpi_osi_setup_late(void)
acpi_status status;
if (osi_linux.default_disabling) {
status = acpi_update_interfaces(ACPI_DISABLE_ALL_VENDOR_STRINGS);
status = acpi_update_interfaces(osi_linux.default_disabling);
if (ACPI_SUCCESS(status))
printk(KERN_INFO PREFIX "Disabled all _OSI OS vendors\n");
printk(KERN_INFO PREFIX "Disabled all _OSI OS vendors%s\n",
osi_linux.default_disabling ==
ACPI_DISABLE_ALL_STRINGS ?
" and feature groups" : "");
}
for (i = 0; i < OSI_STRING_ENTRIES_MAX; i++) {