Hello,
This version of the series is unchanged from v2 except for the last patch which is completely new, and is provided by Mike Rapoport.
Original series description:
A tester ran the upstream selftest on a distro kernel and sounded the alarm when it reported failures for features which aren't included in that kernel.
This patch set improves the test behavior in that scenario.
Changes since v2:
- Added Mike Rapoport's Reviewed-by's and Acked-by's to patches 1-3. - Replaced patch 4/4 by the one provided by Mike Rapoport.
Changes since v1:
- Patch "userfaultfd: selftest: Skip test if userfaultfd() syscall not supported" - New patch, suggested by Mike Rapoport.
- Patch "userfaultfd: selftest: Skip test if a feature isn't supported" - Try running other tests even if one (or more) of them returns KSFT_SKIP.
- Patch "userfaultfd: selftest: Cope if shmem doesn't support zeropage" - Ignore lack of UFFDIO_ZEROPAGE in userfaultfd_events_test() and userfaultfd_stress(). - Make userfaultfd_zeropage_test() return KSFT_SKIP if UFFDIO_ZEROPAGE isn't supported.
Mike Rapoport (1): userfaultfd: selftest: make supported range ioctl verification more robust
Thiago Jung Bauermann (3): userfaultfd: selftest: Fix checking of userfaultfd_open() result userfaultfd: selftest: Skip test if userfaultfd() syscall not supported userfaultfd: selftest: Skip test if a feature isn't supported
tools/testing/selftests/vm/userfaultfd.c | 113 +++++++++++++++++++------------ 1 file changed, 69 insertions(+), 44 deletions(-)
If the userfaultfd test is run on a kernel with CONFIG_USERFAULTFD=n, it will report that the system call is not available yet go ahead and continue anyway:
# ./userfaultfd anon 30 1 nr_pages: 480, nr_pages_per_cpu: 120 userfaultfd syscall not available in this kernel bounces: 0, mode:, register failure
This is because userfaultfd_open() returns 0 on success and 1 on error but all callers assume that it returns < 0 on error.
Since the convention of the test as a whole is the one used by userfault_open(), fix its callers instead. Now the test behaves correctly:
# ./userfaultfd anon 30 1 nr_pages: 480, nr_pages_per_cpu: 120 userfaultfd syscall not available in this kernel
Signed-off-by: Thiago Jung Bauermann bauerman@linux.ibm.com Reviewed-by: Mike Rapoport rppt@linux.vnet.ibm.com --- tools/testing/selftests/vm/userfaultfd.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index 7b8171e3128a..e4099afe7557 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -859,7 +859,7 @@ static int userfaultfd_zeropage_test(void) if (uffd_test_ops->release_pages(area_dst)) return 1;
- if (userfaultfd_open(0) < 0) + if (userfaultfd_open(0)) return 1; uffdio_register.range.start = (unsigned long) area_dst; uffdio_register.range.len = nr_pages * page_size; @@ -902,7 +902,7 @@ static int userfaultfd_events_test(void)
features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP | UFFD_FEATURE_EVENT_REMOVE; - if (userfaultfd_open(features) < 0) + if (userfaultfd_open(features)) return 1; fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
@@ -961,7 +961,7 @@ static int userfaultfd_sig_test(void) return 1;
features = UFFD_FEATURE_EVENT_FORK|UFFD_FEATURE_SIGBUS; - if (userfaultfd_open(features) < 0) + if (userfaultfd_open(features)) return 1; fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
@@ -1027,7 +1027,7 @@ static int userfaultfd_stress(void) if (!area_dst) return 1;
- if (userfaultfd_open(0) < 0) + if (userfaultfd_open(0)) return 1;
count_verify = malloc(nr_pages * sizeof(unsigned long long));
Since there's no point in doing anything in this case, immediately exit the process.
And take the opportunity to improve the error message.
Before:
# ./userfaultfd shmem 10 10 nr_pages: 160, nr_pages_per_cpu: 40 userfaultfd syscall not available in this kernel # echo $? 1
After:
# ./userfaultfd shmem 10 10 nr_pages: 160, nr_pages_per_cpu: 40 userfaultfd syscall not available in this kernel: Function not implemented # echo $? 4
Suggested-by: Mike Rapoport rppt@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann bauerman@linux.ibm.com Acked-by: Mike Rapoport rppt@linux.vnet.ibm.com --- tools/testing/selftests/vm/userfaultfd.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index e4099afe7557..d728bd1cb33c 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -636,9 +636,11 @@ static int userfaultfd_open(int features)
uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK); if (uffd < 0) { - fprintf(stderr, - "userfaultfd syscall not available in this kernel\n"); - return 1; + int errnum = errno; + + perror("userfaultfd syscall not available in this kernel"); + + exit(errnum == ENOSYS ? KSFT_SKIP : 1); } uffd_flags = fcntl(uffd, F_GETFD, NULL);
If userfaultfd runs on a system that doesn't support some feature it is trying to test, it currently ends with error code 1 which indicates test failure:
# ./userfaultfd anon 10 10 nr_pages: 160, nr_pages_per_cpu: 80 bounces: 9, mode: rnd poll, userfaults: 7 59 bounces: 8, mode: poll, userfaults: 0 0 bounces: 7, mode: rnd racing ver, userfaults: 45 2 bounces: 6, mode: racing ver, userfaults: 3 1 bounces: 5, mode: rnd ver, userfaults: 55 32 bounces: 4, mode: ver, userfaults: 69 0 bounces: 3, mode: rnd racing, userfaults: 1 1 bounces: 2, mode: racing, userfaults: 65 0 bounces: 1, mode: rnd, userfaults: 44 1 bounces: 0, mode:, userfaults: 3 2 testing UFFDIO_ZEROPAGE: done. testing signal delivery: UFFDIO_API # echo $? 1
Make each test return KSFT_SKIP instead, which is more accurate since it is not a real test failure and try to run the other tests which may still work:
# ./userfaultfd anon 10 10 nr_pages: 160, nr_pages_per_cpu: 80 bounces: 9, mode: rnd poll, userfaults: 65 27 bounces: 8, mode: poll, userfaults: 0 0 bounces: 7, mode: rnd racing ver, userfaults: 60 29 bounces: 6, mode: racing ver, userfaults: 58 1 bounces: 5, mode: rnd ver, userfaults: 69 3 bounces: 4, mode: ver, userfaults: 35 27 bounces: 3, mode: rnd racing, userfaults: 44 0 bounces: 2, mode: racing, userfaults: 40 25 bounces: 1, mode: rnd, userfaults: 2 1 bounces: 0, mode:, userfaults: 0 1 testing UFFDIO_ZEROPAGE: done. testing signal delivery: UFFDIO_API: Invalid argument testing events (fork, remap, remove): userfaults: 160 # echo $? 0
While at it, also improve the error message of the ioctl(UFFDIO_API) call.
Signed-off-by: Thiago Jung Bauermann bauerman@linux.ibm.com Acked-by: Mike Rapoport rppt@linux.vnet.ibm.com --- tools/testing/selftests/vm/userfaultfd.c | 42 +++++++++++++++++++++++--------- 1 file changed, 30 insertions(+), 12 deletions(-)
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index d728bd1cb33c..c84e44ddf314 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -647,8 +647,11 @@ static int userfaultfd_open(int features) uffdio_api.api = UFFD_API; uffdio_api.features = features; if (ioctl(uffd, UFFDIO_API, &uffdio_api)) { - fprintf(stderr, "UFFDIO_API\n"); - return 1; + int errnum = errno; + + perror("UFFDIO_API"); + + return errnum == EINVAL ? KSFT_SKIP : 1; } if (uffdio_api.api != UFFD_API) { fprintf(stderr, "UFFDIO_API error %Lu\n", uffdio_api.api); @@ -854,6 +857,7 @@ static int userfaultfd_zeropage_test(void) { struct uffdio_register uffdio_register; unsigned long expected_ioctls; + int err;
printf("testing UFFDIO_ZEROPAGE: "); fflush(stdout); @@ -861,8 +865,10 @@ static int userfaultfd_zeropage_test(void) if (uffd_test_ops->release_pages(area_dst)) return 1;
- if (userfaultfd_open(0)) - return 1; + err = userfaultfd_open(0); + if (err) + return err; + uffdio_register.range.start = (unsigned long) area_dst; uffdio_register.range.len = nr_pages * page_size; uffdio_register.mode = UFFDIO_REGISTER_MODE_MISSING; @@ -904,8 +910,10 @@ static int userfaultfd_events_test(void)
features = UFFD_FEATURE_EVENT_FORK | UFFD_FEATURE_EVENT_REMAP | UFFD_FEATURE_EVENT_REMOVE; - if (userfaultfd_open(features)) - return 1; + err = userfaultfd_open(features); + if (err) + return err; + fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
uffdio_register.range.start = (unsigned long) area_dst; @@ -963,8 +971,9 @@ static int userfaultfd_sig_test(void) return 1;
features = UFFD_FEATURE_EVENT_FORK|UFFD_FEATURE_SIGBUS; - if (userfaultfd_open(features)) - return 1; + err = userfaultfd_open(features); + if (err) + return err; fcntl(uffd, F_SETFL, uffd_flags | O_NONBLOCK);
uffdio_register.range.start = (unsigned long) area_dst; @@ -1029,8 +1038,9 @@ static int userfaultfd_stress(void) if (!area_dst) return 1;
- if (userfaultfd_open(0)) - return 1; + err = userfaultfd_open(0); + if (err) + return err;
count_verify = malloc(nr_pages * sizeof(unsigned long long)); if (!count_verify) { @@ -1201,8 +1211,16 @@ static int userfaultfd_stress(void) return err;
close(uffd); - return userfaultfd_zeropage_test() || userfaultfd_sig_test() - || userfaultfd_events_test(); + + err = userfaultfd_zeropage_test(); + if (err && err != KSFT_SKIP) + return err; + + err = userfaultfd_sig_test(); + if (err && err != KSFT_SKIP) + return err; + + return userfaultfd_events_test(); }
/*
From: Mike Rapoport rppt@linux.vnet.ibm.com
When userfaultfd tests runs on older kernel that does not support UFFDIO_ZEROPAGE for shared memory it fails at the ioctl verification.
Split out the verification that supported ioctls are superset of the expected ioctls and relax the checks for UFFDIO_ZEROPAGE for shared memory areas.
Signed-off-by: Mike Rapoport rppt@linux.vnet.ibm.com Signed-off-by: Thiago Jung Bauermann bauerman@linux.ibm.com --- tools/testing/selftests/vm/userfaultfd.c | 63 +++++++++++++++++--------------- 1 file changed, 34 insertions(+), 29 deletions(-)
diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c index c84e44ddf314..676cbedff3db 100644 --- a/tools/testing/selftests/vm/userfaultfd.c +++ b/tools/testing/selftests/vm/userfaultfd.c @@ -271,6 +271,32 @@ static int my_bcmp(char *str1, char *str2, size_t n) return 0; }
+static int verify_ioctls(unsigned long supported_ioctls) +{ + unsigned long expected_ioctls = uffd_test_ops->expected_ioctls; + + if ((supported_ioctls & expected_ioctls) == expected_ioctls) + return 0; + + /* + * For older kernels shared memory may not have UFFDIO_ZEROPAGE. + * In this case we just mask it out from the + * expected_ioctls. The userfaultfd_zeropage_test will then + * verify that an attempt to use UFFDIO_ZEROPAGE returns + * EINVAL + */ + if (test_type == TEST_SHMEM) { + expected_ioctls &= ~(1 << _UFFDIO_ZEROPAGE); + if ((supported_ioctls & expected_ioctls) == expected_ioctls) { + uffd_test_ops->expected_ioctls = expected_ioctls; + return 0; + } + } + + fprintf(stderr, "unexpected missing ioctl\n"); + return 1; +} + static void *locking_thread(void *arg) { unsigned long cpu = (unsigned long) arg; @@ -856,7 +882,6 @@ static int uffdio_zeropage(int ufd, unsigned long offset) static int userfaultfd_zeropage_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; int err;
printf("testing UFFDIO_ZEROPAGE: "); @@ -875,12 +900,8 @@ static int userfaultfd_zeropage_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) fprintf(stderr, "register failure\n"), exit(1);
- expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != - expected_ioctls) - fprintf(stderr, - "unexpected missing ioctl for anon memory\n"), - exit(1); + if (verify_ioctls(uffdio_register.ioctls)) + return 1;
if (uffdio_zeropage(uffd, 0)) { if (my_bcmp(area_dst, zeropage, page_size)) @@ -895,7 +916,6 @@ static int userfaultfd_zeropage_test(void) static int userfaultfd_events_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; unsigned long userfaults; pthread_t uffd_mon; int err, features; @@ -922,12 +942,8 @@ static int userfaultfd_events_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) fprintf(stderr, "register failure\n"), exit(1);
- expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != - expected_ioctls) - fprintf(stderr, - "unexpected missing ioctl for anon memory\n"), - exit(1); + if (verify_ioctls(uffdio_register.ioctls)) + return 1;
if (pthread_create(&uffd_mon, &attr, uffd_poll_thread, NULL)) perror("uffd_poll_thread create"), exit(1); @@ -957,7 +973,6 @@ static int userfaultfd_events_test(void) static int userfaultfd_sig_test(void) { struct uffdio_register uffdio_register; - unsigned long expected_ioctls; unsigned long userfaults; pthread_t uffd_mon; int err, features; @@ -982,12 +997,8 @@ static int userfaultfd_sig_test(void) if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) fprintf(stderr, "register failure\n"), exit(1);
- expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != - expected_ioctls) - fprintf(stderr, - "unexpected missing ioctl for anon memory\n"), - exit(1); + if (verify_ioctls(uffdio_register.ioctls)) + return 1;
if (faulting_process(1)) fprintf(stderr, "faulting process failed\n"), exit(1); @@ -1088,8 +1099,6 @@ static int userfaultfd_stress(void)
err = 0; while (bounces--) { - unsigned long expected_ioctls; - printf("bounces: %d, mode:", bounces); if (bounces & BOUNCE_RANDOM) printf(" rnd"); @@ -1115,13 +1124,9 @@ static int userfaultfd_stress(void) fprintf(stderr, "register failure\n"); return 1; } - expected_ioctls = uffd_test_ops->expected_ioctls; - if ((uffdio_register.ioctls & expected_ioctls) != - expected_ioctls) { - fprintf(stderr, - "unexpected missing ioctl for anon memory\n"); + + if (verify_ioctls(uffdio_register.ioctls)) return 1; - }
if (area_dst_alias) { uffdio_register.range.start = (unsigned long)
linux-kselftest-mirror@lists.linaro.org
-
Thiago Jung Bauermann