Resguardo inicial

linux-7.2.3/arch/s390/kernel/nospec-sysfs.c

@@ -0,0 +1,23 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/device.h>
+#include <linux/cpu.h>
+#include <asm/facility.h>
+#include <asm/nospec-branch.h>
+
+ssize_t cpu_show_spectre_v1(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "Mitigation: __user pointer sanitization\n");
+}
+
+ssize_t cpu_show_spectre_v2(struct device *dev,
+			    struct device_attribute *attr, char *buf)
+{
+	if (test_facility(156))
+		return sysfs_emit(buf, "Mitigation: etokens\n");
+	if (nospec_uses_trampoline())
+		return sysfs_emit(buf, "Mitigation: execute trampolines\n");
+	if (nobp_enabled())
+		return sysfs_emit(buf, "Mitigation: limited branch prediction\n");
+	return sysfs_emit(buf, "Vulnerable\n");
+}