xref: /openbmc/linux/arch/s390/kernel/nospec-sysfs.c (revision 4253b0e0627ee3461e64c2495c616f1c8f6b127b)
1*4253b0e0SMartin Schwidefsky // SPDX-License-Identifier: GPL-2.0
2*4253b0e0SMartin Schwidefsky #include <linux/device.h>
3*4253b0e0SMartin Schwidefsky #include <linux/cpu.h>
4*4253b0e0SMartin Schwidefsky #include <asm/facility.h>
5*4253b0e0SMartin Schwidefsky #include <asm/nospec-branch.h>
6*4253b0e0SMartin Schwidefsky 
7*4253b0e0SMartin Schwidefsky ssize_t cpu_show_spectre_v1(struct device *dev,
8*4253b0e0SMartin Schwidefsky 			    struct device_attribute *attr, char *buf)
9*4253b0e0SMartin Schwidefsky {
10*4253b0e0SMartin Schwidefsky 	return sprintf(buf, "Mitigation: __user pointer sanitization\n");
11*4253b0e0SMartin Schwidefsky }
12*4253b0e0SMartin Schwidefsky 
13*4253b0e0SMartin Schwidefsky ssize_t cpu_show_spectre_v2(struct device *dev,
14*4253b0e0SMartin Schwidefsky 			    struct device_attribute *attr, char *buf)
15*4253b0e0SMartin Schwidefsky {
16*4253b0e0SMartin Schwidefsky 	if (IS_ENABLED(CC_USING_EXPOLINE) && !nospec_disable)
17*4253b0e0SMartin Schwidefsky 		return sprintf(buf, "Mitigation: execute trampolines\n");
18*4253b0e0SMartin Schwidefsky 	if (__test_facility(82, S390_lowcore.alt_stfle_fac_list))
19*4253b0e0SMartin Schwidefsky 		return sprintf(buf, "Mitigation: limited branch prediction\n");
20*4253b0e0SMartin Schwidefsky 	return sprintf(buf, "Vulnerable\n");
21*4253b0e0SMartin Schwidefsky }
22