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1// SPDX-License-Identifier: GPL-2.02#include <linux/perf_event.h>3#include <cpuid.h>4#include <errno.h>5#include <stdio.h>6#include <stdlib.h>7#include <string.h>8#include <sys/ioctl.h>9#include <sys/syscall.h>10#include <unistd.h>11 12int main(void)13{14 struct perf_event_attr ret_attr, mret_attr;15 long long count_rets, count_rets_mispred;16 int rrets_fd, mrrets_fd;17 unsigned int cpuid1_eax, b, c, d;18 19 __cpuid(1, cpuid1_eax, b, c, d);20 21 if (cpuid1_eax < 0x00800f00 ||22 cpuid1_eax > 0x00afffff) {23 fprintf(stderr, "This needs to run on a Zen[1-4] machine (CPUID(1).EAX: 0x%x). Exiting...\n", cpuid1_eax);24 exit(EXIT_FAILURE);25 }26 27 memset(&ret_attr, 0, sizeof(struct perf_event_attr));28 memset(&mret_attr, 0, sizeof(struct perf_event_attr));29 30 ret_attr.type = mret_attr.type = PERF_TYPE_RAW;31 ret_attr.size = mret_attr.size = sizeof(struct perf_event_attr);32 ret_attr.config = 0xc8;33 mret_attr.config = 0xc9;34 ret_attr.disabled = mret_attr.disabled = 1;35 ret_attr.exclude_user = mret_attr.exclude_user = 1;36 ret_attr.exclude_hv = mret_attr.exclude_hv = 1;37 38 rrets_fd = syscall(SYS_perf_event_open, &ret_attr, 0, -1, -1, 0);39 if (rrets_fd == -1) {40 perror("opening retired RETs fd");41 exit(EXIT_FAILURE);42 }43 44 mrrets_fd = syscall(SYS_perf_event_open, &mret_attr, 0, -1, -1, 0);45 if (mrrets_fd == -1) {46 perror("opening retired mispredicted RETs fd");47 exit(EXIT_FAILURE);48 }49 50 ioctl(rrets_fd, PERF_EVENT_IOC_RESET, 0);51 ioctl(mrrets_fd, PERF_EVENT_IOC_RESET, 0);52 53 ioctl(rrets_fd, PERF_EVENT_IOC_ENABLE, 0);54 ioctl(mrrets_fd, PERF_EVENT_IOC_ENABLE, 0);55 56 printf("Sleeping for 10 seconds\n");57 sleep(10);58 59 ioctl(rrets_fd, PERF_EVENT_IOC_DISABLE, 0);60 ioctl(mrrets_fd, PERF_EVENT_IOC_DISABLE, 0);61 62 read(rrets_fd, &count_rets, sizeof(long long));63 read(mrrets_fd, &count_rets_mispred, sizeof(long long));64 65 printf("RETs: (%lld retired <-> %lld mispredicted)\n",66 count_rets, count_rets_mispred);67 printf("SRSO Safe-RET mitigation works correctly if both counts are almost equal.\n");68 69 return 0;70}71