s390/kernel/nospec-sysfs.c

0001 // SPDX-License-Identifier: GPL-2.0
0002 #include <linux/device.h>
0003 #include <linux/cpu.h>
0004 #include <asm/facility.h>
0005 #include <asm/nospec-branch.h>
0006
0007 ssize_t cpu_show_spectre_v1(struct device *dev,
0008                 struct device_attribute *attr, char *buf)
0009 {
0010     return sprintf(buf, "Mitigation: __user pointer sanitization\n");
0011 }
0012
0013 ssize_t cpu_show_spectre_v2(struct device *dev,
0014                 struct device_attribute *attr, char *buf)
0015 {
0016     if (test_facility(156))
0017         return sprintf(buf, "Mitigation: etokens\n");
0018     if (nospec_uses_trampoline())
0019         return sprintf(buf, "Mitigation: execute trampolines\n");
0020     if (__test_facility(82, alt_stfle_fac_list))
0021         return sprintf(buf, "Mitigation: limited branch prediction\n");
0022     return sprintf(buf, "Vulnerable\n");
0023 }