On Wed, Dec 1, 2021 at 3:06 PM Mark Pearson [off-list ref] wrote:

On 2021-11-25 05:36, Hans de Goede wrote:

quoted

Using write_support=1 with the ec_sys module changes the mode of the
"io" debugfs file to 0600. This will cause any attempts to access it under
a kernel in lockdown mode to return -EPERM, which makes the entire ec_sys
module unusable.

Use the special module_param_hw() macro for module parameters which
may not be used while in lockdown mode, to avoid this.

Cc: Mark Pearson <redacted>
Signed-off-by: Hans de Goede <redacted>
---
 drivers/acpi/ec_sys.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/acpi/ec_sys.c b/drivers/acpi/ec_sys.c
index fd39c14493ab..c074a0fae059 100644
--- a/drivers/acpi/ec_sys.c
+++ b/drivers/acpi/ec_sys.c

@@ -19,7 +19,7 @@ MODULE_DESCRIPTION("ACPI EC sysfs access driver");
 MODULE_LICENSE("GPL");

 static bool write_support;
-module_param(write_support, bool, 0644);
+module_param_hw(write_support, bool, other, 0644);
 MODULE_PARM_DESC(write_support, "Dangerous, reboot and removal of battery may "
               "be needed.");

Looks good to me. Thanks Hans
Mark

Patch applied as 5.17 material, thanks!