kernel/linux.git/tools/testing/selftests/vm/userfaultfd.c, branch v5.10.89

selftest: fix build error in tools/testing/selftests/vm/userfaultfd.c

2021-08-04T10:46:39+00:00

When backporting 0db282ba2c12 ("selftest: use mmap instead of posix_memalign to allocate memory") to this stable branch, I forgot a { breaking the build. Signed-off-by: Greg Kroah-Hartman

selftest: use mmap instead of posix_memalign to allocate memory

2021-07-28T12:35:46+00:00

commit 0db282ba2c12c1515d490d14a1ff696643ab0f1b upstream. This test passes pointers obtained from anon_allocate_area to the userfaultfd and mremap APIs. This causes a problem if the system allocator returns tagged pointers because with the tagged address ABI the kernel rejects tagged addresses passed to these APIs, which would end up causing the test to fail. To make this test compatible with such system allocators, stop using the system allocator to allocate memory in anon_allocate_area, and instead just use mmap. Link: https://lkml.kernel.org/r/20210714195437.118982-3-pcc@google.com Link: https://linux-review.googlesource.com/id/Icac91064fcd923f77a83e8e133f8631c5b8fc241 Fixes: c47174fc362a ("userfaultfd: selftest") Co-developed-by: Lokesh Gidra Signed-off-by: Lokesh Gidra Signed-off-by: Peter Collingbourne Reviewed-by: Catalin Marinas Cc: Vincenzo Frascino Cc: Dave Martin Cc: Will Deacon Cc: Andrea Arcangeli Cc: Alistair Delva Cc: William McVicker Cc: Evgenii Stepanov Cc: Mitch Phillips Cc: Andrey Konovalov Cc: [5.4] Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman

userfaultfd: selftests: fix SIGSEGV if huge mmap fails

2020-12-06T18:19:07+00:00

The error handling in hugetlb_allocate_area() was incorrect for the hugetlb_shared test case. Previously the behavior was: - mmap a hugetlb area - If this fails, set the pointer to NULL, and carry on - mmap an alias of the same hugetlb fd - If this fails, munmap the original area If the original mmap failed, it's likely the second one did too. If both failed, we'd blindly try to munmap a NULL pointer, causing a SIGSEGV. Instead, "goto fail" so we return before trying to mmap the alias. This issue can be hit "in real life" by forgetting to set /proc/sys/vm/nr_hugepages (leaving it at 0), and then trying to run the hugetlb_shared test. Another small improvement is, when the original mmap fails, don't just print "it failed": perror(), so we can see *why*. :) Signed-off-by: Axel Rasmussen Signed-off-by: Andrew Morton Cc: Shuah Khan Cc: Peter Xu Cc: Joe Perches Cc: Mike Rapoport Cc: Andrea Arcangeli Cc: David Alan Gilbert Link: https://lkml.kernel.org/r/20201204203443.2714693-1-axelrasmussen@google.com Signed-off-by: Linus Torvalds

tools: Avoid comma separated statements

2020-10-02T16:36:36+00:00

Use semicolons and braces. Signed-off-by: Joe Perches Signed-off-by: Shuah Khan

userfaultfd: selftests: add write-protect test

2020-04-07T17:43:40+00:00

Add uffd tests for write protection. Instead of introducing new tests for it, let's simply squashing uffd-wp tests into existing uffd-missing test cases. Changes are: (1) Bouncing tests We do the write-protection in two ways during the bouncing test: - By using UFFDIO_COPY_MODE_WP when resolving MISSING pages: then we'll make sure for each bounce process every single page will be at least fault twice: once for MISSING, once for WP. - By direct call UFFDIO_WRITEPROTECT on existing faulted memories: To further torture the explicit page protection procedures of uffd-wp, we split each bounce procedure into two halves (in the background thread): the first half will be MISSING+WP for each page as explained above. After the first half, we write protect the faulted region in the background thread to make sure at least half of the pages will be write protected again which is the first half to test the new UFFDIO_WRITEPROTECT call. Then we continue with the 2nd half, which will contain both MISSING and WP faulting tests for the 2nd half and WP-only faults from the 1st half. (2) Event/Signal test Mostly previous tests but will do MISSING+WP for each page. For sigbus-mode test we'll need to provide standalone path to handle the write protection faults. For all tests, do statistics as well for uffd-wp pages. Signed-off-by: Peter Xu Signed-off-by: Andrew Morton Cc: Andrea Arcangeli Cc: Bobby Powers Cc: Brian Geffon Cc: David Hildenbrand Cc: Denis Plotnikov Cc: "Dr . David Alan Gilbert" Cc: Hugh Dickins Cc: Jerome Glisse Cc: Johannes Weiner Cc: "Kirill A . Shutemov" Cc: Martin Cracauer Cc: Marty McFadden Cc: Maya Gokhale Cc: Mel Gorman Cc: Mike Kravetz Cc: Mike Rapoport Cc: Pavel Emelyanov Cc: Rik van Riel Cc: Shaohua Li Link: http://lkml.kernel.org/r/20200220163112.11409-20-peterx@redhat.com Signed-off-by: Linus Torvalds

userfaultfd: selftests: refactor statistics

2020-04-07T17:43:40+00:00

Introduce uffd_stats structure for statistics of the self test, at the same time refactor the code to always pass in the uffd_stats for either read() or poll() typed fault handling threads instead of using two different ways to return the statistic results. No functional change. With the new structure, it's very easy to introduce new statistics. Signed-off-by: Peter Xu Signed-off-by: Andrew Morton Reviewed-by: Mike Rapoport Cc: Andrea Arcangeli Cc: Bobby Powers Cc: Brian Geffon Cc: David Hildenbrand Cc: Denis Plotnikov Cc: "Dr . David Alan Gilbert" Cc: Hugh Dickins Cc: Jerome Glisse Cc: Johannes Weiner Cc: "Kirill A . Shutemov" Cc: Martin Cracauer Cc: Marty McFadden Cc: Maya Gokhale Cc: Mel Gorman Cc: Mike Kravetz Cc: Pavel Emelyanov Cc: Rik van Riel Cc: Shaohua Li Link: http://lkml.kernel.org/r/20200220163112.11409-19-peterx@redhat.com Signed-off-by: Linus Torvalds

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 499

2019-06-19T15:09:53+00:00

Based on 1 normalized pattern(s): this work is licensed under the terms of the gnu gpl version 2 see the copying file in the top level directory extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 35 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Kate Stewart Reviewed-by: Enrico Weigelt Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.797835076@linutronix.de Signed-off-by: Greg Kroah-Hartman

userfaultfd: selftest: fix compiler warning

2019-05-30T14:21:36+00:00

Fixes following compiler warning userfaultfd.c: In function ‘usage’: userfaultfd.c:126:2: warning: format not a string literal and no format arguments [-Wformat-security] fprintf(stderr, examples); Signed-off-by: Alakesh Haloi Reviewed-by: Peter Xu Reviewed-by: Mike Rapoport Signed-off-by: Shuah Khan

userfaultfd: selftest: recycle lock threads first

2018-10-26T23:26:35+00:00

Now we recycle the uffd servicing threads earlier than the lock threads. It might happen that when the lock thread is still blocked at a pthread mutex lock while the servicing thread has already quitted for the cpu so the lock thread will be blocked forever and hang the test program. To fix the possible race, recycle the lock threads first. This never happens with current missing-only tests, but when I start to run the write-protection tests (the feature is not yet posted upstream) it happens every time of the run possibly because in that new test we'll need to service two page faults for each lock operation. Link: http://lkml.kernel.org/r/20180930074259.18229-4-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: Mike Rapoport Cc: Shuah Khan Cc: Mike Kravetz Cc: Jerome Glisse Cc: Zi Yan Cc: "Kirill A . Shutemov" Cc: Shaohua Li Cc: Andrea Arcangeli Cc: "Dr . David Alan Gilbert" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

userfaultfd: selftest: generalize read and poll

2018-10-26T23:26:35+00:00

We do very similar things in read and poll modes, but we're copying the codes around. Share the codes properly on reading the message and handling the page fault to make the code cleaner. Meanwhile this solves previous mismatch of behaviors between the two modes on that the old code: - did not check EAGAIN case in read() mode - ignored BOUNCE_VERIFY check in read() mode Link: http://lkml.kernel.org/r/20180930074259.18229-3-peterx@redhat.com Signed-off-by: Peter Xu Acked-by: Mike Rapoport Cc: Shuah Khan Cc: Mike Kravetz Cc: Jerome Glisse Cc: Zi Yan Cc: "Kirill A . Shutemov" Cc: Shaohua Li Cc: Andrea Arcangeli Cc: "Dr . David Alan Gilbert" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds