13 Commits

Author SHA1 Message Date
Peter Xu
760aee0b71 selftests/mm: add tests for RO pinning vs fork()
Add a test suite (with 10 more sub-tests) to cover RO pinning against
fork() over uffd-wp.  It covers both:

  (1) Early CoW test in fork() when page pinned,
  (2) page unshare due to RO longterm pin.

They are:

  Testing wp-fork-pin on anon... done
  Testing wp-fork-pin on shmem... done
  Testing wp-fork-pin on shmem-private... done
  Testing wp-fork-pin on hugetlb... done
  Testing wp-fork-pin on hugetlb-private... done
  Testing wp-fork-pin-with-event on anon... done
  Testing wp-fork-pin-with-event on shmem... done
  Testing wp-fork-pin-with-event on shmem-private... done
  Testing wp-fork-pin-with-event on hugetlb... done
  Testing wp-fork-pin-with-event on hugetlb-private... done

CONFIG_GUP_TEST needed or they'll be skipped.

  Testing wp-fork-pin on anon... skipped [reason: Possibly CONFIG_GUP_TEST missing or unprivileged]

Note that the major test goal is on private memory, but no hurt to also run
all of them over shared because shared memory should work the same.

Link: https://lkml.kernel.org/r/20230417195317.898696-7-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mika Penttilä <mpenttil@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-21 14:52:00 -07:00
Peter Xu
cff2945827 selftests/mm: extend and rename uffd pagemap test
Extend it to all types of mem, meanwhile add one parallel test when
EVENT_FORK is enabled, where uffd-wp bits should be persisted rather than
dropped.

Since at it, rename the test to "wp-fork" to better show what it means. 
Making the new test called "wp-fork-with-event".

Before:

        Testing pagemap on anon... done

After:

        Testing wp-fork on anon... done
        Testing wp-fork on shmem... done
        Testing wp-fork on shmem-private... done
        Testing wp-fork on hugetlb... done
        Testing wp-fork on hugetlb-private... done
        Testing wp-fork-with-event on anon... done
        Testing wp-fork-with-event on shmem... done
        Testing wp-fork-with-event on shmem-private... done
        Testing wp-fork-with-event on hugetlb... done
        Testing wp-fork-with-event on hugetlb-private... done

Link: https://lkml.kernel.org/r/20230417195317.898696-5-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Mika Penttilä <mpenttil@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-21 14:52:00 -07:00
Peter Xu
21337f2af1 selftests/mm: add a few options for uffd-unit-test
Namely:

  "-f": add a wildcard filter for tests to run
  "-l": list tests rather than running any
  "-h": help msg

Link: https://lkml.kernel.org/r/20230417195317.898696-4-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mika Penttilä <mpenttil@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Nadav Amit <nadav.amit@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-21 14:52:00 -07:00
Peter Xu
43759d44dc selftests/mm: add uffdio register ioctls test
This new test tests against the returned ioctls from UFFDIO_REGISTER,
where put into uffdio_register.ioctls.

This also tests the expected failure cases of UFFDIO_REGISTER, aka:

  - Register with empty mode should fail with -EINVAL
  - Register minor without page cache (anon) should fail with -EINVAL

Link: https://lkml.kernel.org/r/20230412164548.329376-1-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>
2023-04-18 16:30:08 -07:00
Peter Xu
f9da24263d selftests/mm: allow uffd test to skip properly with no privilege
Allow skip a unit test properly due to no privilege (e.g.  sigbus and
events tests).

[colin.i.king@gmail.com: fix spelling mistake "priviledge" -> "privilege"]
  Link: https://lkml.kernel.org/r/20230414081506.1678998-1-colin.i.king@gmail.com
Link: https://lkml.kernel.org/r/20230412164520.329163-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Colin Ian King <colin.i.king@gmail.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>
2023-04-18 16:30:08 -07:00
Peter Xu
4df9cefa94 selftests/mm: workaround no way to detect uffd-minor + wp
Userfaultfd minor+wp mode was very recently added.  The test will fail on
the old kernels at ioctl(UFFDIO_CONTINUE) which is misterious. 
Unfortunately there's no feature bit to detect for this support.

Add a hack to leverage WP_UNPOPULATED to detect whether that feature
existed, since WP_UNPOPULATED was merged right after minor+wp.

Link: https://lkml.kernel.org/r/20230412164517.329152-1-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>
2023-04-18 16:30:07 -07:00
Peter Xu
c3315502c9 selftests/mm: move zeropage test into uffd unit tests
Simplifies it a bit along the way, e.g., drop the never used offset field
(which was always the 1st page so offset=0).

Introduce uffd_register_with_ioctls() out of uffd_register() to detect
uffdio_register.ioctls got returned.  Check that automatically when testing
UFFDIO_ZEROPAGE on different types of memory (and kernel).

Link: https://lkml.kernel.org/r/20230412164404.328815-1-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>
2023-04-18 16:30:07 -07:00
Peter Xu
73c1ea939b selftests/mm: move uffd sig/events tests into uffd unit tests
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>
2023-04-18 16:30:07 -07:00
Peter Xu
62515b5f9f selftests/mm: move uffd minor test to unit test
This moves the minor test to the new unit test.

Rewrite the content check with char* opeartions to avoid fiddling with
my_bcmp().

Drop global vars test_uffdio_minor and test_collapse, just assume test them
always in common code for now.

OTOH make this single test into five tests:

  - minor test on [shmem, hugetlb] with wp=false
  - minor test on [shmem, hugetlb] with wp=true
  - minor test + collapse on shmem only

One thing to mention that we used to test COLLAPSE+WP but that doesn't
sound right at all.  It's possible it's silently broken but unnoticed
because COLLAPSE is not part of the default test suite.

Make the MADV_COLLAPSE test fail-able (by skip it when failing), because
it's not guaranteed to success anyway.

Drop a bunch of useless code after the move, because the unit test always
use aligned num of pages and has nothing to do with n_cpus.

Link: https://lkml.kernel.org/r/20230412164357.328779-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Cc: Zach O'Keefe <zokeefe@google.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>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 16:30:07 -07:00
Peter Xu
8bda424fca selftests/mm: move uffd pagemap test to unit test
Move it over and make it split into two tests, one for pagemap and one for
the new WP_UNPOPULATED (to be a separate one).

The thp pagemap test wasn't really working (with MADV_HUGEPAGE).  Let's
just drop it (since it never really worked anyway..) and leave that for
later.

Link: https://lkml.kernel.org/r/20230412164352.328733-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
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: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 16:30:07 -07:00
Peter Xu
16a45b57cb selftests/mm: add framework for uffd-unit-test
Add a framework to be prepared to move unit tests from uffd-stress.c into
uffd-unit-tests.c.  The goal is to allow detection of uffd features for
each test, and also loop over specified types of memory that a test
support.

Link: https://lkml.kernel.org/r/20230412164348.328710-1-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>
2023-04-18 16:30:06 -07:00
Peter Xu
d5433ce84d selftests/mm: UFFDIO_API test
Add one simple test for UFFDIO_API.  With that, I also added a bunch of
small but handy helpers along the way.

Link: https://lkml.kernel.org/r/20230412164257.328375-1-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>
2023-04-18 16:30:05 -07:00
Peter Xu
686a8bb723 selftests/mm: split uffd tests into uffd-stress and uffd-unit-tests
In many ways it's weird and unwanted to keep all the tests in the same
userfaultfd.c at least when still in the current way.

For example, it doesn't make much sense to run the stress test for each
method we can create an userfaultfd handle (either via syscall or /dev/
node).  It's a waste of time running this twice for the whole stress as
the stress paths are the same, only the open path is different.

It's also just weird to need to manually specify different types of memory
to run all unit tests for the userfaultfd interface.  We should be able to
just run a single program and that should go through all functional uffd
tests without running the stress test at all.  The stress test was more
for torturing and finding race conditions.  We don't want to wait for
stress to finish just to regress test a functional test.

When we start to pile up more things on top of the same file and same
functions, things start to go a bit chaos and the code is just harder to
maintain too with tons of global variables.

This patch creates a new test uffd-unit-tests to keep userfaultfd unit
tests in the future, currently empty.

Meanwhile rename the old userfaultfd.c test to uffd-stress.c.

Link: https://lkml.kernel.org/r/20230412164244.328270-1-peterx@redhat.com
Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by: Mike Rapoport (IBM) <rppt@kernel.org>
Reviewed-by: 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: Zach O'Keefe <zokeefe@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2023-04-18 16:30:04 -07:00