powerpc/watchpoint: Add DAR outside test in perf-hwbreak.c selftest
authorRavi Bangoria <ravi.bangoria@linux.ibm.com>
Thu, 17 Oct 2019 09:32:03 +0000 (15:02 +0530)
committerMichael Ellerman <mpe@ellerman.id.au>
Wed, 13 Nov 2019 05:58:04 +0000 (16:58 +1100)
So far we used to ignore exception if DAR points outside of user
specified range. But now we are ignoring it only if actual load/store
range does not overlap with user specified range. Include selftests
for the same:

  # ./tools/testing/selftests/powerpc/ptrace/perf-hwbreak
  ...
  TESTED: No overlap
  TESTED: Partial overlap
  TESTED: Partial overlap
  TESTED: No overlap
  TESTED: Full overlap
  success: perf_hwbreak

Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191017093204.7511-7-ravi.bangoria@linux.ibm.com
tools/testing/selftests/powerpc/ptrace/perf-hwbreak.c

index 200337d..c1f324a 100644 (file)
@@ -148,6 +148,121 @@ static int runtestsingle(int readwriteflag, int exclude_user, int arraytest)
        return 0;
 }
 
+static int runtest_dar_outside(void)
+{
+       void *target;
+       volatile __u16 temp16;
+       volatile __u64 temp64;
+       struct perf_event_attr attr;
+       int break_fd;
+       unsigned long long breaks;
+       int fail = 0;
+       size_t res;
+
+       target = malloc(8);
+       if (!target) {
+               perror("malloc failed");
+               exit(EXIT_FAILURE);
+       }
+
+       /* setup counters */
+       memset(&attr, 0, sizeof(attr));
+       attr.disabled = 1;
+       attr.type = PERF_TYPE_BREAKPOINT;
+       attr.exclude_kernel = 1;
+       attr.exclude_hv = 1;
+       attr.exclude_guest = 1;
+       attr.bp_type = HW_BREAKPOINT_RW;
+       /* watch middle half of target array */
+       attr.bp_addr = (__u64)(target + 2);
+       attr.bp_len = 4;
+       break_fd = sys_perf_event_open(&attr, 0, -1, -1, 0);
+       if (break_fd < 0) {
+               free(target);
+               perror("sys_perf_event_open");
+               exit(EXIT_FAILURE);
+       }
+
+       /* Shouldn't hit. */
+       ioctl(break_fd, PERF_EVENT_IOC_RESET);
+       ioctl(break_fd, PERF_EVENT_IOC_ENABLE);
+       temp16 = *((__u16 *)target);
+       *((__u16 *)target) = temp16;
+       ioctl(break_fd, PERF_EVENT_IOC_DISABLE);
+       res = read(break_fd, &breaks, sizeof(unsigned long long));
+       assert(res == sizeof(unsigned long long));
+       if (breaks == 0) {
+               printf("TESTED: No overlap\n");
+       } else {
+               printf("FAILED: No overlap: %lld != 0\n", breaks);
+               fail = 1;
+       }
+
+       /* Hit */
+       ioctl(break_fd, PERF_EVENT_IOC_RESET);
+       ioctl(break_fd, PERF_EVENT_IOC_ENABLE);
+       temp16 = *((__u16 *)(target + 1));
+       *((__u16 *)(target + 1)) = temp16;
+       ioctl(break_fd, PERF_EVENT_IOC_DISABLE);
+       res = read(break_fd, &breaks, sizeof(unsigned long long));
+       assert(res == sizeof(unsigned long long));
+       if (breaks == 2) {
+               printf("TESTED: Partial overlap\n");
+       } else {
+               printf("FAILED: Partial overlap: %lld != 2\n", breaks);
+               fail = 1;
+       }
+
+       /* Hit */
+       ioctl(break_fd, PERF_EVENT_IOC_RESET);
+       ioctl(break_fd, PERF_EVENT_IOC_ENABLE);
+       temp16 = *((__u16 *)(target + 5));
+       *((__u16 *)(target + 5)) = temp16;
+       ioctl(break_fd, PERF_EVENT_IOC_DISABLE);
+       res = read(break_fd, &breaks, sizeof(unsigned long long));
+       assert(res == sizeof(unsigned long long));
+       if (breaks == 2) {
+               printf("TESTED: Partial overlap\n");
+       } else {
+               printf("FAILED: Partial overlap: %lld != 2\n", breaks);
+               fail = 1;
+       }
+
+       /* Shouldn't Hit */
+       ioctl(break_fd, PERF_EVENT_IOC_RESET);
+       ioctl(break_fd, PERF_EVENT_IOC_ENABLE);
+       temp16 = *((__u16 *)(target + 6));
+       *((__u16 *)(target + 6)) = temp16;
+       ioctl(break_fd, PERF_EVENT_IOC_DISABLE);
+       res = read(break_fd, &breaks, sizeof(unsigned long long));
+       assert(res == sizeof(unsigned long long));
+       if (breaks == 0) {
+               printf("TESTED: No overlap\n");
+       } else {
+               printf("FAILED: No overlap: %lld != 0\n", breaks);
+               fail = 1;
+       }
+
+       /* Hit */
+       ioctl(break_fd, PERF_EVENT_IOC_RESET);
+       ioctl(break_fd, PERF_EVENT_IOC_ENABLE);
+       temp64 = *((__u64 *)target);
+       *((__u64 *)target) = temp64;
+       ioctl(break_fd, PERF_EVENT_IOC_DISABLE);
+       res = read(break_fd, &breaks, sizeof(unsigned long long));
+       assert(res == sizeof(unsigned long long));
+       if (breaks == 2) {
+               printf("TESTED: Full overlap\n");
+       } else {
+               printf("FAILED: Full overlap: %lld != 2\n", breaks);
+               fail = 1;
+       }
+
+       free(target);
+       close(break_fd);
+       return fail;
+}
+
 static int runtest(void)
 {
        int rwflag;
@@ -172,7 +287,9 @@ static int runtest(void)
                                return ret;
                }
        }
-       return 0;
+
+       ret = runtest_dar_outside();
+       return ret;
 }