[PATCH 4.17 23/67] thunderbolt: Notify userspace when boot_acl is changed

[Greg Kroah-Hartman]

4.17-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>

commit 007a74907deeceefef9dc3ec4679fbd7921eaa51 upstream.

The commit 9aaa3b8b4c56 ("thunderbolt: Add support for preboot ACL")
introduced boot_acl attribute but missed the fact that now userspace
needs to poll the attribute constantly to find out whether it has
changed or not. Fix this by sending notification to the userspace
whenever the boot_acl attribute is changed.

Fixes: 9aaa3b8b4c56 ("thunderbolt: Add support for preboot ACL")
Reported-and-tested-by: Christian Kellner <christian@xxxxxxxxxx>
Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
Reviewed-by: Christian Kellner <christian@xxxxxxxxxx>
Acked-by: Yehezkel Bernat <yehezkelshb@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/thunderbolt/domain.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/thunderbolt/domain.c
+++ b/drivers/thunderbolt/domain.c
@@ -213,6 +213,10 @@ static ssize_t boot_acl_store(struct dev
 		goto err_free_acl;
 	}
 	ret = tb->cm_ops->set_boot_acl(tb, acl, tb->nboot_acl);
+	if (!ret) {
+		/* Notify userspace about the change */
+		kobject_uevent(&tb->dev.kobj, KOBJ_CHANGE);
+	}
 	mutex_unlock(&tb->lock);
 
 err_free_acl: