Merge branch 'dt' of git://git.kernel.org/pub/scm/linux/kernel/git/ulfh/linux-pm into sunxi/dt-for-6.17

Signed-off-by: Chen-Yu Tsai <wens@csie.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index 6f4203716b53..75c7db8b156a 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -23,8 +23,10 @@
 #include <linux/delay.h>
 #include <linux/interrupt.h>
 #include <linux/list.h>
+#include <linux/printk.h>
 #include <linux/spinlock.h>
 #include <linux/slab.h>
+#include <linux/string.h>
 #include <linux/suspend.h>
 #include <linux/acpi.h>
 #include <linux/dmi.h>
@@ -2031,6 +2033,21 @@ void __init acpi_ec_ecdt_probe(void)
 		goto out;
 	}
 
+	if (!strstarts(ecdt_ptr->id, "\\")) {
+		/*
+		 * The ECDT table on some MSI notebooks contains invalid data, together
+		 * with an empty ID string ("").
+		 *
+		 * Section 5.2.15 of the ACPI specification requires the ID string to be
+		 * a "fully qualified reference to the (...) embedded controller device",
+		 * so this string always has to start with a backslash.
+		 *
+		 * By verifying this we can avoid such faulty ECDT tables in a safe way.
+		 */
+		pr_err(FW_BUG "Ignoring ECDT due to invalid ID string \"%s\"\n", ecdt_ptr->id);
+		goto out;
+	}
+
 	ec = acpi_ec_alloc();
 	if (!ec)
 		goto out;