kernel/tools/testing/selftests/mm/pfnmap.c, branch linux-rolling-stable

selftests: complete kselftest include centralization

2025-11-27T22:24:31Z

This follow-up patch completes centralization of kselftest.h and ksefltest_harness.h includes in remaining seltests files, replacing all relative paths with a non-relative paths using shared -I include path in lib.mk Tested with gcc-13.3 and clang-18.1, and cross-compiled successfully on riscv, arm64, x86_64 and powerpc arch. [reddybalavignesh9979@gmail.com: add selftests include path for kselftest.h] Link: https://lkml.kernel.org/r/20251017090201.317521-1-reddybalavignesh9979@gmail.com Link: https://lkml.kernel.org/r/20251016104409.68985-1-reddybalavignesh9979@gmail.com Signed-off-by: Bala-Vignesh-Reddy Suggested-by: Andrew Morton Link: https://lore.kernel.org/lkml/20250820143954.33d95635e504e94df01930d0@linux-foundation.org/ Reviewed-by: Wei Yang Cc: David Hildenbrand Cc: David S. Miller Cc: Eric Dumazet Cc: Günther Noack Cc: Jakub Kacinski Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Mickael Salaun Cc: Ming Lei Cc: Paolo Abeni Cc: Shuah Khan Cc: Simon Horman Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

selftests/mm: pass filename as input param to VM_PFNMAP tests

2025-09-13T23:54:43Z

Enable these tests to be run on other pfnmap'ed memory like NVIDIA's EGM. Add '--' as a separator to pass in file path. This allows passing of cmd line arguments to kselftest_harness. Use '/dev/mem' as default filename. Existing test passes: pfnmap TAP version 13 1..6 # Starting 6 tests from 1 test cases. # PASSED: 6 / 6 tests passed. # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0 Pass params to kselftest_harness: pfnmap -r pfnmap:mremap_fixed TAP version 13 1..1 # Starting 1 tests from 1 test cases. # RUN pfnmap.mremap_fixed ... # OK pfnmap.mremap_fixed ok 1 pfnmap.mremap_fixed # PASSED: 1 / 1 tests passed. # Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0 Pass non-existent file name as input: pfnmap -- /dev/blah TAP version 13 1..6 # Starting 6 tests from 1 test cases. # RUN pfnmap.madvise_disallowed ... # SKIP Cannot open '/dev/blah' Pass non pfnmap'ed file as input: pfnmap -r pfnmap.madvise_disallowed -- randfile.txt TAP version 13 1..1 # Starting 1 tests from 1 test cases. # RUN pfnmap.madvise_disallowed ... # SKIP Invalid file: 'randfile.txt'. Not pfnmap'ed Link: https://lkml.kernel.org/r/20250805013629.47629-1-sudarsanm@google.com Signed-off-by: Sudarsan Mahendran Acked-by: David Hildenbrand Cc: Axel Rasmussen Cc: Shuah Khan Signed-off-by: Andrew Morton

selftests/mm: two fixes for the pfnmap test

2025-06-01T05:46:14Z

When unregistering the signal handler, we have to pass SIG_DFL, and blindly reading from PFN 0 and PFN 1 seems to be problematic on !x86 systems. In particularly, on arm64 tx2 machines where noting resides at these physical memory locations, we can generate RAS errors. Let's fix it by scanning /proc/iomem for actual "System RAM". Link: https://lkml.kernel.org/r/20250528195244.1182810-1-david@redhat.com Fixes: 2616b370323a ("selftests/mm: add simple VM_PFNMAP tests based on mmap'ing /dev/mem") Signed-off-by: David Hildenbrand Reported-by: Ryan Roberts Closes: https://lore.kernel.org/all/232960c2-81db-47ca-a337-38c4bce5f997@arm.com/T/#u Reviewed-by: Ryan Roberts Tested-by: Aishwarya TCV Cc: Shuah Khan Cc: Lorenzo Stoakes Signed-off-by: Andrew Morton

selftests/mm: add simple VM_PFNMAP tests based on mmap'ing /dev/mem

2025-05-22T21:55:36Z

Let's test some basic functionality using /dev/mem. These tests will implicitly cover some PAT (Page Attribute Handling) handling on x86. These tests will only run when /dev/mem access to the first two pages in physical address space is possible and allowed; otherwise, the tests are skipped. On current x86-64 with PAT inside a VM, all tests pass: TAP version 13 1..6 # Starting 6 tests from 1 test cases. # RUN pfnmap.madvise_disallowed ... # OK pfnmap.madvise_disallowed ok 1 pfnmap.madvise_disallowed # RUN pfnmap.munmap_split ... # OK pfnmap.munmap_split ok 2 pfnmap.munmap_split # RUN pfnmap.mremap_fixed ... # OK pfnmap.mremap_fixed ok 3 pfnmap.mremap_fixed # RUN pfnmap.mremap_shrink ... # OK pfnmap.mremap_shrink ok 4 pfnmap.mremap_shrink # RUN pfnmap.mremap_expand ... # OK pfnmap.mremap_expand ok 5 pfnmap.mremap_expand # RUN pfnmap.fork ... # OK pfnmap.fork ok 6 pfnmap.fork # PASSED: 6 / 6 tests passed. # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0 However, we are able to trigger: [ 27.888251] x86/PAT: pfnmap:1790 freeing invalid memtype [mem 0x00000000-0x00000fff] There are probably more things worth testing in the future, such as MAP_PRIVATE handling. But this set of tests is sufficient to cover most of the things we will rework regarding PAT handling. Link: https://lkml.kernel.org/r/20250509153033.952746-1-david@redhat.com Signed-off-by: David Hildenbrand Reviewed-by: Lorenzo Stoakes Cc: Shuah Khan Cc: Ingo Molnar Cc: Peter Xu Cc: Dev Jain Signed-off-by: Andrew Morton