The idea was trying to flip this var in the alarm handler from time to time to test -EEXIST of UFFDIO_ZEROPAGE, but firstly it's only used in the zeropage test so probably only used once, meanwhile we passed "retry==false" so it'll never got tested anyway. Drop both sides so we always test UFFDIO_ZEROPAGE retries if has_zeropage is set (!hugetlb). One more thing to do is doing UFFDIO_REGISTER for the alias buffer too, because otherwise the test won't even pass! We were just lucky that this test never really got ran at all. Signed-off-by: Peter Xu <peterx@xxxxxxxxxx> --- tools/testing/selftests/mm/userfaultfd.c | 20 +++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/tools/testing/selftests/mm/userfaultfd.c b/tools/testing/selftests/mm/userfaultfd.c index d724f1c78847..3487ec0bfcc8 100644 --- a/tools/testing/selftests/mm/userfaultfd.c +++ b/tools/testing/selftests/mm/userfaultfd.c @@ -88,7 +88,6 @@ static bool test_dev_userfaultfd; /* exercise the test_uffdio_*_eexist every ALARM_INTERVAL_SECS */ #define ALARM_INTERVAL_SECS 10 static volatile bool test_uffdio_copy_eexist = true; -static volatile bool test_uffdio_zeropage_eexist = true; /* Whether to test uffd write-protection */ static bool test_uffdio_wp = true; /* Whether to test uffd minor faults */ @@ -1114,7 +1113,7 @@ static void retry_uffdio_zeropage(int ufd, } } -static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) +static int __uffdio_zeropage(int ufd, unsigned long offset) { struct uffdio_zeropage uffdio_zeropage; int ret; @@ -1138,11 +1137,8 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) if (res != page_size) { err("UFFDIO_ZEROPAGE unexpected size"); } else { - if (test_uffdio_zeropage_eexist && retry) { - test_uffdio_zeropage_eexist = false; - retry_uffdio_zeropage(ufd, &uffdio_zeropage, - offset); - } + retry_uffdio_zeropage(ufd, &uffdio_zeropage, + offset); return 1; } } else @@ -1153,7 +1149,7 @@ static int __uffdio_zeropage(int ufd, unsigned long offset, bool retry) static int uffdio_zeropage(int ufd, unsigned long offset) { - return __uffdio_zeropage(ufd, offset, false); + return __uffdio_zeropage(ufd, offset); } /* exercise UFFDIO_ZEROPAGE */ @@ -1177,6 +1173,13 @@ static int userfaultfd_zeropage_test(void) assert_expected_ioctls_present( uffdio_register.mode, uffdio_register.ioctls); + if (area_dst_alias) { + /* Needed this to test zeropage-retry on shared memory */ + uffdio_register.range.start = (unsigned long) area_dst_alias; + if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) + err("register failure"); + } + if (uffdio_zeropage(uffd, 0)) if (my_bcmp(area_dst, zeropage, page_size)) err("zeropage is not zero"); @@ -1763,7 +1766,6 @@ static void sigalrm(int sig) if (sig != SIGALRM) abort(); test_uffdio_copy_eexist = true; - test_uffdio_zeropage_eexist = true; alarm(ALARM_INTERVAL_SECS); } -- 2.39.1