[PATCH] ACPI / EC: Mark the ec_sys write_support param as module_param_hw()

From: Hans de Goede <hdegoede@redhat.com>
To: "Rafael J . Wysocki" <rjw@rjwysocki.net>
Cc: Hans de Goede <hdegoede@redhat.com>, Len Brown <lenb@kernel.org>,
	linux-acpi@vger.kernel.org, Mark Pearson <markpearson@lenovo.com>
Subject: [PATCH] ACPI / EC: Mark the ec_sys write_support param as module_param_hw()
Date: Thu, 25 Nov 2021 11:36:16 +0100	[thread overview]
Message-ID: <20211125103616.47742-1-hdegoede@redhat.com> (raw)

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 <markpearson@lenovo.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
---
 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.");
 
-- 
2.33.1

