linux.git/tools/testing/selftests/mm/uffd-common.c, branch for-next

Revert "selftests/mm: replace atomic_bool with pthread_barrier_t"

2024-10-29T04:40:41+00:00

This reverts commit e61ef21e27e8deed8c474e9f47f4aa7bc37e138c.

uffd_poll_thread may be called by other tests that do not initialize the
pthread_barrier, so this approach is not correct.  This will revert to
using atomic_bool instead.

Link: https://lkml.kernel.org/r/20241018171734.2315053-3-edliaw@google.com
Fixes: e61ef21e27e8 ("selftests/mm: replace atomic_bool with pthread_barrier_t")
Signed-off-by: Edward Liaw 
Cc: Ryan Roberts 
Cc: Peter Xu 
Cc: Shuah Khan 
Cc: 
Signed-off-by: Andrew Morton

selftests/mm: replace atomic_bool with pthread_barrier_t

2024-10-17T07:28:06+00:00

Patch series "selftests/mm: fix deadlock after pthread_create".

On Android arm, pthread_create followed by a fork caused a deadlock in the
case where the fork required work to be completed by the created thread.

Update the synchronization primitive to use pthread_barrier instead of
atomic_bool.

Apply the same fix to the wp-fork-with-event test.


This patch (of 2):

Swap synchronization primitive with pthread_barrier, so that stdatomic.h
does not need to be included.

The synchronization is needed on Android ARM64; we see a deadlock with
pthread_create when the parent thread races forward before the child has a
chance to start doing work.

Link: https://lkml.kernel.org/r/20241003211716.371786-1-edliaw@google.com
Link: https://lkml.kernel.org/r/20241003211716.371786-2-edliaw@google.com
Fixes: cff294582798 ("selftests/mm: extend and rename uffd pagemap test")
Signed-off-by: Edward Liaw 
Cc: Lokesh Gidra 
Cc: Peter Xu 
Cc: Shuah Khan 
Cc: 
Signed-off-by: Andrew Morton

selftests/mm: remove local __NR_* definitions

2024-07-04T02:30:16+00:00

This continues the work on getting the selftests to build without
requiring people to first run "make headers" [1].

Now that the system call numbers are in the correct, checked-in locations
in the kernel tree (./tools/include/uapi/asm/unistd*.h), make sure that
the mm selftests include that file (indirectly).

Doing so provides guaranteed definitions at build time, so remove all of
the checks for "ifdef __NR_xxx" in the mm selftests, because they will
always be true (defined).

[1] commit e076eaca5906 ("selftests: break the dependency upon local
header files")

Link: https://lkml.kernel.org/r/20240618022422.804305-7-jhubbard@nvidia.com
Signed-off-by: John Hubbard 
Acked-by: David Hildenbrand 
Cc: Jeff Xu 
Cc: Andrei Vagin 
Cc: Axel Rasmussen 
Cc: Christian Brauner 
Cc: Kees Cook 
Cc: Kent Overstreet 
Cc: Liam R. Howlett 
Cc: Muhammad Usama Anjum 
Cc: Peter Xu 
Cc: Rich Felker 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/mm: fix ARM related issue with fork after pthread_create

2024-03-26T18:14:12+00:00

Following issue was observed while running the uffd-unit-tests selftest
on ARM devices. On x86_64 no issues were detected:

pthread_create followed by fork caused deadlock in certain cases wherein
fork required some work to be completed by the created thread.  Used
synchronization to ensure that created thread's start function has started
before invoking fork.

[edliaw@google.com: refactored to use atomic_bool]
Link: https://lkml.kernel.org/r/20240325194100.775052-1-edliaw@google.com
Fixes: 760aee0b71e3 ("selftests/mm: add tests for RO pinning vs fork()")
Signed-off-by: Lokesh Gidra 
Signed-off-by: Edward Liaw 
Cc: Peter Xu 
Cc: 
Signed-off-by: Andrew Morton

selftests/mm: add UFFDIO_MOVE ioctl test

2023-12-29T19:58:24+00:00

Add tests for new UFFDIO_MOVE ioctl which uses uffd to move source into
destination buffer while checking the contents of both after the move. 
After the operation the content of the destination buffer should match the
original source buffer's content while the source buffer should be zeroed.
Separate tests are designed for PMD aligned and unaligned cases because
they utilize different code paths in the kernel.

Link: https://lkml.kernel.org/r/20231206103702.3873743-6-surenb@google.com
Signed-off-by: Suren Baghdasaryan 
Cc: Al Viro 
Cc: Andrea Arcangeli 
Cc: Axel Rasmussen 
Cc: Brian Geffon 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Hugh Dickins 
Cc: Jann Horn 
Cc: Kalesh Singh 
Cc: Liam R. Howlett 
Cc: Lokesh Gidra 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Mike Rapoport (IBM) 
Cc: Nicolas Geoffray 
Cc: Peter Xu 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: ZhangPeng 
Signed-off-by: Andrew Morton

selftests/mm: add uffd_test_case_ops to allow test case-specific operations

2023-12-29T19:58:24+00:00

Currently each test can specify unique operations using uffd_test_ops,
however these operations are per-memory type and not per-test.  Add
uffd_test_case_ops which each test case can customize for its own needs
regardless of the memory type being used.  Pre- and post-allocation
operations are added, some of which will be used in the next patch to
implement test-specific operations like madvise after memory is allocated
but before it is accessed.

Link: https://lkml.kernel.org/r/20231206103702.3873743-5-surenb@google.com
Signed-off-by: Suren Baghdasaryan 
Cc: Al Viro 
Cc: Andrea Arcangeli 
Cc: Axel Rasmussen 
Cc: Brian Geffon 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Hugh Dickins 
Cc: Jann Horn 
Cc: Kalesh Singh 
Cc: Liam R. Howlett 
Cc: Lokesh Gidra 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Mike Rapoport (IBM) 
Cc: Nicolas Geoffray 
Cc: Peter Xu 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: ZhangPeng 
Signed-off-by: Andrew Morton

selftests/mm: call uffd_test_ctx_clear at the end of the test

2023-12-29T19:58:24+00:00

uffd_test_ctx_clear() is being called from uffd_test_ctx_init() to unmap
areas used in the previous test run.  This approach is problematic because
while unmapping areas uffd_test_ctx_clear() uses page_size and nr_pages
which might differ from one test run to another.  Fix this by calling
uffd_test_ctx_clear() after each test is done.

Link: https://lkml.kernel.org/r/20231206103702.3873743-4-surenb@google.com
Signed-off-by: Suren Baghdasaryan 
Reviewed-by: Peter Xu 
Reviewed-by: Axel Rasmussen 
Cc: Al Viro 
Cc: Andrea Arcangeli 
Cc: Brian Geffon 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Hugh Dickins 
Cc: Jann Horn 
Cc: Kalesh Singh 
Cc: Liam R. Howlett 
Cc: Lokesh Gidra 
Cc: Matthew Wilcox (Oracle) 
Cc: Michal Hocko 
Cc: Mike Rapoport (IBM) 
Cc: Nicolas Geoffray 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: ZhangPeng 
Signed-off-by: Andrew Morton

selftests/mm: refactor uffd_poll_thread to allow custom fault handlers

2023-08-18T17:12:17+00:00

Previously, we had "one fault handler to rule them all", which used
several branches to deal with all of the scenarios required by all of the
various tests.

In upcoming patches, I plan to add a new test, which has its own slightly
different fault handling logic.  Instead of continuing to add cruft to the
existing fault handler, let's allow tests to define custom ones, separate
from other tests.

Link: https://lkml.kernel.org/r/20230707215540.2324998-8-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen 
Acked-by: Peter Xu 
Cc: Al Viro 
Cc: Brian Geffon 
Cc: Christian Brauner 
Cc: David Hildenbrand 
Cc: Gaosheng Cui 
Cc: Huang, Ying 
Cc: Hugh Dickins 
Cc: James Houghton 
Cc: Jan Alexander Steffens (heftig) 
Cc: Jiaqi Yan 
Cc: Jonathan Corbet 
Cc: Kefeng Wang 
Cc: Liam R. Howlett 
Cc: Miaohe Lin 
Cc: Mike Kravetz 
Cc: Mike Rapoport (IBM) 
Cc: Muchun Song 
Cc: Nadav Amit 
Cc: Naoya Horiguchi 
Cc: Ryan Roberts 
Cc: Shuah Khan 
Cc: Suleiman Souhlal 
Cc: Suren Baghdasaryan 
Cc: T.J. Alumbaugh 
Cc: Yu Zhao 
Cc: ZhangPeng 
Signed-off-by: Andrew Morton

selftests/mm: move certain uffd*() routines from vm_util.c to uffd-common.c

2023-06-19T23:19:02+00:00

There are only three uffd*() routines that are used outside of the uffd
selftests. Leave these in vm_util.c, where they are available to any mm
selftest program:

    uffd_register()
    uffd_unregister()
    uffd_register_with_ioctls().

A few other uffd*() routines, however, are only used by the uffd-focused
tests found in uffd-stress.c and uffd-unit-tests.c. Move those routines
into uffd-common.c.

Link: https://lkml.kernel.org/r/20230606071637.267103-10-jhubbard@nvidia.com
Signed-off-by: John Hubbard 
Acked-by: David Hildenbrand 
Tested-by: Muhammad Usama Anjum 
Cc: Peter Xu 
Cc: Jonathan Corbet 
Cc: Nathan Chancellor 
Cc: Shuah Khan 
Signed-off-by: Andrew Morton

selftests/mm: drop sys/dev test in uffd-stress test

2023-04-18T23:30:08+00:00

With the new uffd unit test covering the /dev/userfaultfd path and syscall
path of uffd initializations, we can safely drop the devnode test in the
old stress test.

One thing is to avoid duplication of running the stress test twice which is
an overkill to only test the /dev/ interface in run_vmtests.sh.

The other benefit is now all uffd tests (that uses userfaultfd_open) can
run automatically as long as any type of interface is enabled (either
syscall or dev), so it's more likely to succeed rather than fail due to
unprivilege.

With this patch lands, we can drop all the "mem_type:XXX" handlings too.

Link: https://lkml.kernel.org/r/20230412164525.329176-1-peterx@redhat.com
Signed-off-by: Peter Xu 
Cc: Axel Rasmussen 
Cc: David Hildenbrand 
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Mike Kravetz 
Cc: Mike Rapoport (IBM) 
Cc: Zach O'Keefe 
Signed-off-by: Andrew Morton