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

Merge tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

2025-12-06T22:01:20Z

Pull non-MM updates from Andrew Morton: - "panic: sys_info: Refactor and fix a potential issue" (Andy Shevchenko) fixes a build issue and does some cleanup in ib/sys_info.c - "Implement mul_u64_u64_div_u64_roundup()" (David Laight) enhances the 64-bit math code on behalf of a PWM driver and beefs up the test module for these library functions - "scripts/gdb/symbols: make BPF debug info available to GDB" (Ilya Leoshkevich) makes BPF symbol names, sizes, and line numbers available to the GDB debugger - "Enable hung_task and lockup cases to dump system info on demand" (Feng Tang) adds a sysctl which can be used to cause additional info dumping when the hung-task and lockup detectors fire - "lib/base64: add generic encoder/decoder, migrate users" (Kuan-Wei Chiu) adds a general base64 encoder/decoder to lib/ and migrates several users away from their private implementations - "rbree: inline rb_first() and rb_last()" (Eric Dumazet) makes TCP a little faster - "liveupdate: Rework KHO for in-kernel users" (Pasha Tatashin) reworks the KEXEC Handover interfaces in preparation for Live Update Orchestrator (LUO), and possibly for other future clients - "kho: simplify state machine and enable dynamic updates" (Pasha Tatashin) increases the flexibility of KEXEC Handover. Also preparation for LUO - "Live Update Orchestrator" (Pasha Tatashin) is a major new feature targeted at cloud environments. Quoting the cover letter: This series introduces the Live Update Orchestrator, a kernel subsystem designed to facilitate live kernel updates using a kexec-based reboot. This capability is critical for cloud environments, allowing hypervisors to be updated with minimal downtime for running virtual machines. LUO achieves this by preserving the state of selected resources, such as memory, devices and their dependencies, across the kernel transition. As a key feature, this series includes support for preserving memfd file descriptors, which allows critical in-memory data, such as guest RAM or any other large memory region, to be maintained in RAM across the kexec reboot. Mike Rappaport merits a mention here, for his extensive review and testing work. - "kexec: reorganize kexec and kdump sysfs" (Sourabh Jain) moves the kexec and kdump sysfs entries from /sys/kernel/ to /sys/kernel/kexec/ and adds back-compatibility symlinks which can hopefully be removed one day - "kho: fixes for vmalloc restoration" (Mike Rapoport) fixes a BUG which was being hit during KHO restoration of vmalloc() regions * tag 'mm-nonmm-stable-2025-12-06-11-14' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (139 commits) calibrate: update header inclusion Reinstate "resource: avoid unnecessary lookups in find_next_iomem_res()" vmcoreinfo: track and log recoverable hardware errors kho: fix restoring of contiguous ranges of order-0 pages kho: kho_restore_vmalloc: fix initialization of pages array MAINTAINERS: TPM DEVICE DRIVER: update the W-tag init: replace simple_strtoul with kstrtoul to improve lpj_setup KHO: fix boot failure due to kmemleak access to non-PRESENT pages Documentation/ABI: new kexec and kdump sysfs interface Documentation/ABI: mark old kexec sysfs deprecated kexec: move sysfs entries to /sys/kernel/kexec test_kho: always print restore status kho: free chunks using free_page() instead of kfree() selftests/liveupdate: add kexec test for multiple and empty sessions selftests/liveupdate: add simple kexec-based selftest for LUO selftests/liveupdate: add userspace API selftests docs: add documentation for memfd preservation via LUO mm: memfd_luo: allow preserving memfd liveupdate: luo_file: add private argument to store runtime state mm: shmem: export some functions to internal.h ...

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

selftest/mm: fix pointer comparison in mremap_test

2025-11-20T21:43:57Z

Pointer arthemitic with 'void * addr' and 'ulong dest_alignment' triggers following warning: mremap_test.c:1035:31: warning: pointer comparison always evaluates to false [-Wtautological-compare] 1035 | if (addr + c.dest_alignment < addr) { | ^ this warning is raised from clang version 20.1.8 (Fedora 20.1.8-4.fc42). use 'void *tmp_addr' to do the pointer arthemitic. Link: https://lkml.kernel.org/r/20251108161829.25105-1-ankitkhushwaha.linux@gmail.com Signed-off-by: Ankit Khushwaha Acked-by: Mike Rapoport (Microsoft) Cc: Liam Howlett Cc: Lorenzo Stoakes Cc: Michal Hocko Cc: Shuah Khan Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

selftests/mm: fix spelling mistake "mrmeap" -> "mremap"

2025-09-13T23:54:59Z

There are spelling mistakes in perror messages. Fix these. Link: https://lkml.kernel.org/r/20250813081333.1978096-1-colin.i.king@gmail.com Signed-off-by: Colin Ian King Reviewed-by: Lorenzo Stoakes Signed-off-by: Andrew Morton

selftests/mm: add test for invalid multi VMA operations

2025-08-19T23:35:55Z

We can use UFFD to easily assert invalid multi VMA moves, so do so, asserting expected behaviour when VMAs invalid for a multi VMA operation are encountered. We assert both that such operations are not permitted, and that we do not even attempt to move the first VMA under these circumstances. We also assert that we can still move a single VMA regardless. We then assert that a partial failure can occur if the invalid VMA appears later in the range of multiple VMAs, both at the very next VMA, and also at the end of the range. As part of this change, we are using the is_range_valid() helper more aggressively. Therefore, fix a bug where stale buffered data would hang around on success, causing subsequent calls to is_range_valid() to potentially give invalid results. We simply have to fflush() the stream on success to resolve this issue. Link: https://lkml.kernel.org/r/c4fb86dd5ba37610583ad5fc0e0c2306ddf318b9.1754218667.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: David Hildenbrand Cc: Jann Horn Cc: Liam Howlett Cc: Michal Hocko Cc: Mike Rapoport Cc: Suren Baghdasaryan Cc: Vlastimil Babka Signed-off-by: Andrew Morton

tools/testing/selftests: explicitly test split multi VMA mremap move

2025-07-25T02:12:42Z

Check that moving a range of VMAs where we are offset into the first and last VMAs works correctly. This results in the VMAs being split at these points at which we are offset into VMAs. We explicitly test both the ordinary MREMAP_FIXED multi VMA move case and the MREMAP_DONTUNMAP multi VMA move case. Link: https://lkml.kernel.org/r/b04920bb6c09dc86c207c251eab8ec670fbbcaef.1753119043.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Jann Horn Cc: Liam Howlett Cc: Vlastimil Babka Signed-off-by: Andrew Morton

tools/testing/selftests: test MREMAP_DONTUNMAP on multiple VMA move

2025-07-25T02:12:42Z

We support MREMAP_MAYMOVE | MREMAP_FIXED | MREMAP_DONTUNMAP for moving multiple VMAs via mremap(), so assert that the tests pass with both MREMAP_DONTUNMAP set and not set. Additionally, add success = false settings when mremap() fails. This is something that cannot realistically happen, so in no way impacted test outcome, but it is incorrect to indicate a test pass when something has failed. Link: https://lkml.kernel.org/r/d7359941981e4e44c774753b3e364d1c54928e6a.1753119043.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Jann Horn Cc: Liam Howlett Cc: Vlastimil Babka Signed-off-by: Andrew Morton

tools/testing/selftests: add mremap() shrink test for multiple VMAs

2025-07-25T02:12:42Z

Patch series "tools/testing: expand mremap testing". Expand our mremap() testing to further assert that behaviour is as expected. There is a poorly documented mremap() feature whereby it is possible to mremap() multiple VMAs (even with gaps) when shrinking, as long as the resultant shrunk range spans only a single VMA. So we start by asserting this behaviour functions correctly both with an in-place shrink and a shrink/move. Next, we further test the newly introduced ability to mremap() multiple VMAs when performing a MAP_FIXED move (that is without the size being changed), firstly by asserting that MREMAP_DONTUNMAP has no bearing on this behaviour. Finally, we explicitly test that such moves, when splitting source VMAs, function correctly. This patch (of 3): There is an apparently little-known feature of mremap() whereby, in stark contrast to other modes (other than the recently introduced capacity to move multiple VMAs), the input source range span multiple VMAs with gaps between. This is, when shrinking a VMA, whether moving it or not, and the shrink would reduce the range to a single VMA - this is permitted, as the shrink is actioned by an unmap. This patch adds tests to assert that this behaves as expected. Link: https://lkml.kernel.org/r/cover.1753119043.git.lorenzo.stoakes@oracle.com Link: https://lkml.kernel.org/r/f08122893a26092a2bec6e69443e87f468ffdbed.1753119043.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Jann Horn Cc: Liam Howlett Cc: Vlastimil Babka Signed-off-by: Andrew Morton

tools/testing/selftests: extend mremap_test to test multi-VMA mremap

2025-07-25T02:12:31Z

Now that we have added the ability to move multiple VMAs at once, assert that this functions correctly, both overwriting VMAs and moving backwards and forwards with merge and VMA invalidation. Additionally assert that page tables are correctly propagated by setting random data and reading it back. Link: https://lkml.kernel.org/r/139074a24a011ca4ed52498a7fa2080024b43917.1752770784.git.lorenzo.stoakes@oracle.com Signed-off-by: Lorenzo Stoakes Cc: Al Viro Cc: Christian Brauner Cc: Jan Kara Cc: Jann Horn Cc: Liam Howlett Cc: Peter Xu Cc: Rik van Riel Cc: Vlastimil Babka Signed-off-by: Andrew Morton

selftests/mm: fix -Wmaybe-uninitialized warnings

2025-01-14T06:40:53Z

A few -Wmaybe-uninitialized warnings show up when building the mm tests with -O2. None of them looks worrying; silence them by initialising the problematic variables. Link: https://lkml.kernel.org/r/20241209095019.1732120-3-kevin.brodsky@arm.com Signed-off-by: Kevin Brodsky Cc: Aruna Ramakrishna Cc: Catalin Marinas Cc: Dave Hansen Cc: Joey Gouly Cc: Keith Lucas Cc: Ryan Roberts Cc: Shuah Khan Signed-off-by: Andrew Morton