selftests/mm: move uffd sig/events tests into uffd unit tests
authorPeter Xu <peterx@redhat.com>
Wed, 12 Apr 2023 16:44:00 +0000 (12:44 -0400)
committerAndrew Morton <akpm@linux-foundation.org>
Tue, 18 Apr 2023 23:30:07 +0000 (16:30 -0700)
Move the two tests into the unit test, and convert it into 20 standalone
tests:

  - events test on all 5 mem types, with wp on/off
  - signal test on all 5 mem types, with wp on/off

  Testing sigbus on anon... done
  Testing sigbus on shmem... done
  Testing sigbus on shmem-private... done
  Testing sigbus on hugetlb... done
  Testing sigbus on hugetlb-private... done
  Testing sigbus-wp on anon... done
  Testing sigbus-wp on shmem... done
  Testing sigbus-wp on shmem-private... done
  Testing sigbus-wp on hugetlb... done
  Testing sigbus-wp on hugetlb-private... done
  Testing events on anon... done
  Testing events on shmem... done
  Testing events on shmem-private... done
  Testing events on hugetlb... done
  Testing events on hugetlb-private... done
  Testing events-wp on anon... done
  Testing events-wp on shmem... done
  Testing events-wp on shmem-private... done
  Testing events-wp on hugetlb... done
  Testing events-wp on hugetlb-private... done

It'll also remove a lot of global references along the way,
e.g. test_uffdio_wp will be replaced with the wp value passed over.

Link: https://lkml.kernel.org/r/20230412164400.328798-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Mike Rapoport (IBM) <rppt@kernel.org>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
tools/testing/selftests/mm/uffd-stress.c
tools/testing/selftests/mm/uffd-unit-tests.c

index f9322bbaf8258313de6e3786fd5f895c35f6f0eb..ce51180238d85b8b99a17589b4813ec70e852072 100644 (file)
@@ -273,133 +273,6 @@ static int stress(struct uffd_args *args)
        return 0;
 }
 
-sigjmp_buf jbuf, *sigbuf;
-
-static void sighndl(int sig, siginfo_t *siginfo, void *ptr)
-{
-       if (sig == SIGBUS) {
-               if (sigbuf)
-                       siglongjmp(*sigbuf, 1);
-               abort();
-       }
-}
-
-/*
- * For non-cooperative userfaultfd test we fork() a process that will
- * generate pagefaults, will mremap the area monitored by the
- * userfaultfd and at last this process will release the monitored
- * area.
- * For the anonymous and shared memory the area is divided into two
- * parts, the first part is accessed before mremap, and the second
- * part is accessed after mremap. Since hugetlbfs does not support
- * mremap, the entire monitored area is accessed in a single pass for
- * HUGETLB_TEST.
- * The release of the pages currently generates event for shmem and
- * anonymous memory (UFFD_EVENT_REMOVE), hence it is not checked
- * for hugetlb.
- * For signal test(UFFD_FEATURE_SIGBUS), signal_test = 1, we register
- * monitored area, generate pagefaults and test that signal is delivered.
- * Use UFFDIO_COPY to allocate missing page and retry. For signal_test = 2
- * test robustness use case - we release monitored area, fork a process
- * that will generate pagefaults and verify signal is generated.
- * This also tests UFFD_FEATURE_EVENT_FORK event along with the signal
- * feature. Using monitor thread, verify no userfault events are generated.
- */
-static int faulting_process(int signal_test, bool wp)
-{
-       unsigned long nr;
-       unsigned long long count;
-       unsigned long split_nr_pages;
-       unsigned long lastnr;
-       struct sigaction act;
-       volatile unsigned long signalled = 0;
-
-       split_nr_pages = (nr_pages + 1) / 2;
-
-       if (signal_test) {
-               sigbuf = &jbuf;
-               memset(&act, 0, sizeof(act));
-               act.sa_sigaction = sighndl;
-               act.sa_flags = SA_SIGINFO;
-               if (sigaction(SIGBUS, &act, 0))
-                       err("sigaction");
-               lastnr = (unsigned long)-1;
-       }
-
-       for (nr = 0; nr < split_nr_pages; nr++) {
-               volatile int steps = 1;
-               unsigned long offset = nr * page_size;
-
-               if (signal_test) {
-                       if (sigsetjmp(*sigbuf, 1) != 0) {
-                               if (steps == 1 && nr == lastnr)
-                                       err("Signal repeated");
-
-                               lastnr = nr;
-                               if (signal_test == 1) {
-                                       if (steps == 1) {
-                                               /* This is a MISSING request */
-                                               steps++;
-                                               if (copy_page(uffd, offset, wp))
-                                                       signalled++;
-                                       } else {
-                                               /* This is a WP request */
-                                               assert(steps == 2);
-                                               wp_range(uffd,
-                                                        (__u64)area_dst +
-                                                        offset,
-                                                        page_size, false);
-                                       }
-                               } else {
-                                       signalled++;
-                                       continue;
-                               }
-                       }
-               }
-
-               count = *area_count(area_dst, nr);
-               if (count != count_verify[nr])
-                       err("nr %lu memory corruption %llu %llu\n",
-                           nr, count, count_verify[nr]);
-               /*
-                * Trigger write protection if there is by writing
-                * the same value back.
-                */
-               *area_count(area_dst, nr) = count;
-       }
-
-       if (signal_test)
-               return signalled != split_nr_pages;
-
-       area_dst = mremap(area_dst, nr_pages * page_size,  nr_pages * page_size,
-                         MREMAP_MAYMOVE | MREMAP_FIXED, area_src);
-       if (area_dst == MAP_FAILED)
-               err("mremap");
-       /* Reset area_src since we just clobbered it */
-       area_src = NULL;
-
-       for (; nr < nr_pages; nr++) {
-               count = *area_count(area_dst, nr);
-               if (count != count_verify[nr]) {
-                       err("nr %lu memory corruption %llu %llu\n",
-                           nr, count, count_verify[nr]);
-               }
-               /*
-                * Trigger write protection if there is by writing
-                * the same value back.
-                */
-               *area_count(area_dst, nr) = count;
-       }
-
-       uffd_test_ops->release_pages(area_dst);
-
-       for (nr = 0; nr < nr_pages; nr++)
-               if (my_bcmp(area_dst + nr * page_size, zeropage, page_size))
-                       err("nr %lu is not zero", nr);
-
-       return 0;
-}
-
 static void retry_uffdio_zeropage(int ufd,
                                  struct uffdio_zeropage *uffdio_zeropage,
                                  unsigned long offset)
@@ -483,103 +356,6 @@ static int userfaultfd_zeropage_test(void)
        return 0;
 }
 
-static int userfaultfd_events_test(void)
-{
-       pthread_t uffd_mon;
-       int err, features;
-       pid_t pid;
-       char c;
-       struct uffd_args args = { 0 };
-
-       printf("testing events (fork, remap, remove): ");
-       fflush(stdout);
-
-       features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP |
-               UFFD_FEATURE_EVENT_REMOVE;
-       uffd_test_ctx_init(features);
-
-       fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
-
-       if (uffd_register(uffd, area_dst, nr_pages * page_size,
-                         true, test_uffdio_wp, false))
-               err("register failure");
-
-       args.apply_wp = test_uffdio_wp;
-       if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &args))
-               err("uffd_poll_thread create");
-
-       pid = fork();
-       if (pid < 0)
-               err("fork");
-
-       if (!pid)
-               exit(faulting_process(0, test_uffdio_wp));
-
-       waitpid(pid, &err, 0);
-       if (err)
-               err("faulting process failed");
-       if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
-               err("pipe write");
-       if (pthread_join(uffd_mon, NULL))
-               return 1;
-
-       uffd_stats_report(&args, 1);
-
-       return args.missing_faults != nr_pages;
-}
-
-static int userfaultfd_sig_test(void)
-{
-       unsigned long userfaults;
-       pthread_t uffd_mon;
-       int err, features;
-       pid_t pid;
-       char c;
-       struct uffd_args args = { 0 };
-
-       printf("testing signal delivery: ");
-       fflush(stdout);
-
-       features = UFFD_FEATURE_EVENT_FORK|UFFD_FEATURE_SIGBUS;
-       uffd_test_ctx_init(features);
-
-       fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
-
-       if (uffd_register(uffd, area_dst, nr_pages * page_size,
-                         true, test_uffdio_wp, false))
-               err("register failure");
-
-       if (faulting_process(1, test_uffdio_wp))
-               err("faulting process failed");
-
-       uffd_test_ops->release_pages(area_dst);
-
-       args.apply_wp = test_uffdio_wp;
-       if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, &args))
-               err("uffd_poll_thread create");
-
-       pid = fork();
-       if (pid < 0)
-               err("fork");
-
-       if (!pid)
-               exit(faulting_process(2, test_uffdio_wp));
-
-       waitpid(pid, &err, 0);
-       if (err)
-               err("faulting process failed");
-       if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
-               err("pipe write");
-       if (pthread_join(uffd_mon, (void **)&userfaults))
-               return 1;
-
-       printf("done.\n");
-       if (userfaults)
-               err("Signal test failed, userfaults: %ld", userfaults);
-
-       return userfaults != 0;
-}
-
 static int userfaultfd_stress(void)
 {
        void *area;
@@ -691,8 +467,7 @@ static int userfaultfd_stress(void)
                uffd_stats_report(args, nr_cpus);
        }
 
-       return userfaultfd_zeropage_test() || userfaultfd_sig_test()
-           || userfaultfd_events_test();
+       return userfaultfd_zeropage_test();
 }
 
 static void set_test_type(const char *type)
index cba04608bdb03cfb3a60f6fff4c4398c79815246..94549696f4b247011dc35c64b157610bdd9c756d 100644 (file)
@@ -18,6 +18,9 @@
 #define  MEM_HUGETLB                      BIT_ULL(3)
 #define  MEM_HUGETLB_PRIVATE              BIT_ULL(4)
 
+#define  MEM_ALL  (MEM_ANON | MEM_SHMEM | MEM_SHMEM_PRIVATE | \
+                  MEM_HUGETLB | MEM_HUGETLB_PRIVATE)
+
 struct mem_type {
        const char *name;
        unsigned int mem_flag;
@@ -426,6 +429,237 @@ void uffd_minor_collapse_test(void)
        uffd_minor_test_common(true, false);
 }
 
+static sigjmp_buf jbuf, *sigbuf;
+
+static void sighndl(int sig, siginfo_t *siginfo, void *ptr)
+{
+       if (sig == SIGBUS) {
+               if (sigbuf)
+                       siglongjmp(*sigbuf, 1);
+               abort();
+       }
+}
+
+/*
+ * For non-cooperative userfaultfd test we fork() a process that will
+ * generate pagefaults, will mremap the area monitored by the
+ * userfaultfd and at last this process will release the monitored
+ * area.
+ * For the anonymous and shared memory the area is divided into two
+ * parts, the first part is accessed before mremap, and the second
+ * part is accessed after mremap. Since hugetlbfs does not support
+ * mremap, the entire monitored area is accessed in a single pass for
+ * HUGETLB_TEST.
+ * The release of the pages currently generates event for shmem and
+ * anonymous memory (UFFD_EVENT_REMOVE), hence it is not checked
+ * for hugetlb.
+ * For signal test(UFFD_FEATURE_SIGBUS), signal_test = 1, we register
+ * monitored area, generate pagefaults and test that signal is delivered.
+ * Use UFFDIO_COPY to allocate missing page and retry. For signal_test = 2
+ * test robustness use case - we release monitored area, fork a process
+ * that will generate pagefaults and verify signal is generated.
+ * This also tests UFFD_FEATURE_EVENT_FORK event along with the signal
+ * feature. Using monitor thread, verify no userfault events are generated.
+ */
+static int faulting_process(int signal_test, bool wp)
+{
+       unsigned long nr, i;
+       unsigned long long count;
+       unsigned long split_nr_pages;
+       unsigned long lastnr;
+       struct sigaction act;
+       volatile unsigned long signalled = 0;
+
+       split_nr_pages = (nr_pages + 1) / 2;
+
+       if (signal_test) {
+               sigbuf = &jbuf;
+               memset(&act, 0, sizeof(act));
+               act.sa_sigaction = sighndl;
+               act.sa_flags = SA_SIGINFO;
+               if (sigaction(SIGBUS, &act, 0))
+                       err("sigaction");
+               lastnr = (unsigned long)-1;
+       }
+
+       for (nr = 0; nr < split_nr_pages; nr++) {
+               volatile int steps = 1;
+               unsigned long offset = nr * page_size;
+
+               if (signal_test) {
+                       if (sigsetjmp(*sigbuf, 1) != 0) {
+                               if (steps == 1 && nr == lastnr)
+                                       err("Signal repeated");
+
+                               lastnr = nr;
+                               if (signal_test == 1) {
+                                       if (steps == 1) {
+                                               /* This is a MISSING request */
+                                               steps++;
+                                               if (copy_page(uffd, offset, wp))
+                                                       signalled++;
+                                       } else {
+                                               /* This is a WP request */
+                                               assert(steps == 2);
+                                               wp_range(uffd,
+                                                        (__u64)area_dst +
+                                                        offset,
+                                                        page_size, false);
+                                       }
+                               } else {
+                                       signalled++;
+                                       continue;
+                               }
+                       }
+               }
+
+               count = *area_count(area_dst, nr);
+               if (count != count_verify[nr])
+                       err("nr %lu memory corruption %llu %llu\n",
+                           nr, count, count_verify[nr]);
+               /*
+                * Trigger write protection if there is by writing
+                * the same value back.
+                */
+               *area_count(area_dst, nr) = count;
+       }
+
+       if (signal_test)
+               return signalled != split_nr_pages;
+
+       area_dst = mremap(area_dst, nr_pages * page_size,  nr_pages * page_size,
+                         MREMAP_MAYMOVE | MREMAP_FIXED, area_src);
+       if (area_dst == MAP_FAILED)
+               err("mremap");
+       /* Reset area_src since we just clobbered it */
+       area_src = NULL;
+
+       for (; nr < nr_pages; nr++) {
+               count = *area_count(area_dst, nr);
+               if (count != count_verify[nr]) {
+                       err("nr %lu memory corruption %llu %llu\n",
+                           nr, count, count_verify[nr]);
+               }
+               /*
+                * Trigger write protection if there is by writing
+                * the same value back.
+                */
+               *area_count(area_dst, nr) = count;
+       }
+
+       uffd_test_ops->release_pages(area_dst);
+
+       for (nr = 0; nr < nr_pages; nr++)
+               for (i = 0; i < page_size; i++)
+                       if (*(area_dst + nr * page_size + i) != 0)
+                               err("page %lu offset %lu is not zero", nr, i);
+
+       return 0;
+}
+
+static void uffd_sigbus_test_common(bool wp)
+{
+       unsigned long userfaults;
+       pthread_t uffd_mon;
+       pid_t pid;
+       int err;
+       char c;
+       struct uffd_args args = { 0 };
+
+       fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+
+       if (uffd_register(uffd, area_dst, nr_pages * page_size,
+                         true, wp, false))
+               err("register failure");
+
+       if (faulting_process(1, wp))
+               err("faulting process failed");
+
+       uffd_test_ops->release_pages(area_dst);
+
+       args.apply_wp = wp;
+       if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
+               err("uffd_poll_thread create");
+
+       pid = fork();
+       if (pid < 0)
+               err("fork");
+
+       if (!pid)
+               exit(faulting_process(2, wp));
+
+       waitpid(pid, &err, 0);
+       if (err)
+               err("faulting process failed");
+       if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+               err("pipe write");
+       if (pthread_join(uffd_mon, (void **)&userfaults))
+               err("pthread_join()");
+
+       if (userfaults)
+               uffd_test_fail("Signal test failed, userfaults: %ld", userfaults);
+       else
+               uffd_test_pass();
+}
+
+static void uffd_sigbus_test(void)
+{
+       uffd_sigbus_test_common(false);
+}
+
+static void uffd_sigbus_wp_test(void)
+{
+       uffd_sigbus_test_common(true);
+}
+
+static void uffd_events_test_common(bool wp)
+{
+       pthread_t uffd_mon;
+       pid_t pid;
+       int err;
+       char c;
+       struct uffd_args args = { 0 };
+
+       fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
+       if (uffd_register(uffd, area_dst, nr_pages * page_size,
+                         true, wp, false))
+               err("register failure");
+
+       args.apply_wp = wp;
+       if (pthread_create(&uffd_mon, NULL, uffd_poll_thread, &args))
+               err("uffd_poll_thread create");
+
+       pid = fork();
+       if (pid < 0)
+               err("fork");
+
+       if (!pid)
+               exit(faulting_process(0, wp));
+
+       waitpid(pid, &err, 0);
+       if (err)
+               err("faulting process failed");
+       if (write(pipefd[1], &c, sizeof(c)) != sizeof(c))
+               err("pipe write");
+       if (pthread_join(uffd_mon, NULL))
+               err("pthread_join()");
+
+       if (args.missing_faults != nr_pages)
+               uffd_test_fail("Fault counts wrong");
+       else
+               uffd_test_pass();
+}
+
+static void uffd_events_test(void)
+{
+       uffd_events_test_common(false);
+}
+
+static void uffd_events_wp_test(void)
+{
+       uffd_events_test_common(true);
+}
+
 uffd_test_case_t uffd_tests[] = {
        {
                .name = "pagemap",
@@ -463,6 +697,36 @@ uffd_test_case_t uffd_tests[] = {
                /* We can't test MADV_COLLAPSE, so try our luck */
                .uffd_feature_required = UFFD_FEATURE_MINOR_SHMEM,
        },
+       {
+               .name = "sigbus",
+               .uffd_fn = uffd_sigbus_test,
+               .mem_targets = MEM_ALL,
+               .uffd_feature_required = UFFD_FEATURE_SIGBUS |
+               UFFD_FEATURE_EVENT_FORK,
+       },
+       {
+               .name = "sigbus-wp",
+               .uffd_fn = uffd_sigbus_wp_test,
+               .mem_targets = MEM_ALL,
+               .uffd_feature_required = UFFD_FEATURE_SIGBUS |
+               UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_PAGEFAULT_FLAG_WP,
+       },
+       {
+               .name = "events",
+               .uffd_fn = uffd_events_test,
+               .mem_targets = MEM_ALL,
+               .uffd_feature_required = UFFD_FEATURE_EVENT_FORK |
+               UFFD_FEATURE_EVENT_REMAP | UFFD_FEATURE_EVENT_REMOVE,
+       },
+       {
+               .name = "events-wp",
+               .uffd_fn = uffd_events_wp_test,
+               .mem_targets = MEM_ALL,
+               .uffd_feature_required = UFFD_FEATURE_EVENT_FORK |
+               UFFD_FEATURE_EVENT_REMAP | UFFD_FEATURE_EVENT_REMOVE |
+               UFFD_FEATURE_PAGEFAULT_FLAG_WP |
+               UFFD_FEATURE_WP_HUGETLBFS_SHMEM,
+       },
 };
 
 int main(int argc, char *argv[])