Commit 618aeb5d authored by Peter Xu's avatar Peter Xu Committed by Andrew Morton
Browse files

selftests/mm: drop test_uffdio_zeropage_eexist 

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.

Link: https://lkml.kernel.org/r/20230412164238.328238-1-peterx@redhat.com


Signed-off-by: default avatarPeter Xu <peterx@redhat.com>
Reviewed-by: default avatarMike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: default avatarDavid Hildenbrand <david@redhat.com>
Reviewed-by: default avatarMike Rapoport (IBM) <rppt@kernel.org>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 4af9ff29

tools/testing/selftests/mm/userfaultfd.c

+11 −9
Original line number Diff line number Diff line
@@ -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);

			}

			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);

}