| Message ID | 20180725024209.32586-2-bauerman@linux.ibm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | userfaultfd: selftest: Improve behavior with older kernels | expand |
Hi, On Tue, Jul 24, 2018 at 11:42:07PM -0300, Thiago Jung Bauermann wrote: > 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> It seems that this patch is superseded by the second patch in this series. > --- > 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));
Hello Mike, Thanks for promptly reviewing the patches. Mike Rapoport <rppt@linux.vnet.ibm.com> writes: > Hi, > > On Tue, Jul 24, 2018 at 11:42:07PM -0300, Thiago Jung Bauermann wrote: >> 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> > > It seems that this patch is superseded by the second patch in this series. Yes, but since this is a simple bugfix while the other patch is a proposed improvement which can be debated, I think it's worthwhile to keep them separate. -- Thiago Jung Bauermann IBM Linux Technology Center -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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));
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> --- tools/testing/selftests/vm/userfaultfd.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html