kernel/tools/testing/selftests/vfio, branch master

vfio: selftests: only build tests on arm64 and x86_64

2026-02-06T22:08:05Z

Only build vfio self-tests on arm64 and x86_64; these are the only architectures where the vfio self-tests are run. Addresses compiler warnings for format and conversions on i386. Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202601211830.aBEjmEFD-lkp@intel.com/ Signed-off-by: Ted Logan Reviewed-by: David Matlack Link: https://lore.kernel.org/r/20260202-vfio-selftest-only-64bit-v2-1-9c3ebb37f0f4@fb.com Signed-off-by: Alex Williamson

vfio: selftests: Drop IOMMU mapping size assertions for VFIO_TYPE1_IOMMU

2026-01-19T17:06:30Z

Drop the assertions about IOMMU mappings sizes for VFIO_TYPE1_IOMMU modes (both the VFIO mode and the iommufd compatibility mode). These assertions fail when CONFIG_IOMMUFD_VFIO_CONTAINER is enabled, since iommufd compatibility mode provides different huge page behavior than VFIO for VFIO_TYPE1_IOMMU. VFIO_TYPE1_IOMMU is an old enough interface that it's not worth changing the behavior of VFIO and iommufd to match nor care about the IOMMU mapping sizes. Cc: Jason Gunthorpe Link: https://lore.kernel.org/kvm/20260109143830.176dc279@shazbot.org/ Signed-off-by: David Matlack Link: https://lore.kernel.org/r/20260114211252.2581145-1-dmatlack@google.com Signed-off-by: Alex Williamson

vfio: selftests: Add vfio_dma_mapping_mmio_test

2026-01-19T17:06:30Z

Test IOMMU mapping the BAR mmaps created during vfio_pci_device_setup(). All IOMMU modes are tested: vfio_type1 variants are expected to succeed, while non-type1 modes are expected to fail. iommufd compat mode can be updated to expect success once kernel support lands. Native iommufd will not support mapping vaddrs backed by MMIO (it will support dma-buf based MMIO mapping instead). Signed-off-by: Alex Mastro Reviewed-by: David Matlack Tested-by: David Matlack Link: https://lore.kernel.org/r/20260114-map-mmio-test-v3-3-44e036d95e64@fb.com Signed-off-by: Alex Williamson

vfio: selftests: Align BAR mmaps for efficient IOMMU mapping

2026-01-19T17:06:30Z

Update vfio_pci_bar_map() to align BAR mmaps for efficient huge page mappings. The manual mmap alignment can be removed once mmap(!MAP_FIXED) on vfio device fds improves to automatically return well-aligned addresses. Also add MADV_HUGEPAGE, which encourages the kernel to use huge pages (e.g. when /sys/kernel/mm/transparent_hugepage/enabled is set to "madvise"). Drop MAP_FILE from mmap(). It is an ignored compatibility flag. Signed-off-by: Alex Mastro Reviewed-by: David Matlack Tested-by: David Matlack Link: https://lore.kernel.org/r/20260114-map-mmio-test-v3-2-44e036d95e64@fb.com Signed-off-by: Alex Williamson

vfio: selftests: Centralize IOMMU mode name definitions

2026-01-19T17:06:29Z

Replace scattered string literals with MODE_* macros in iommu.h. This provides a single source of truth for IOMMU mode name strings. Signed-off-by: Alex Mastro Reviewed-by: David Matlack Tested-by: David Matlack Link: https://lore.kernel.org/r/20260114-map-mmio-test-v3-1-44e036d95e64@fb.com Signed-off-by: Alex Williamson

vfio: selftests: Drop includes

2025-12-23T21:17:13Z

Drop the includes now that (tools/include/linux/types.h) has a definition for __aligned_le64, which is needed by . Including is harmless but causes benign typedef redefinitions. This is not a problem for VFIO selftests but becomes an issue when the VFIO selftests library is built into KVM selftests, since they are built with -std=gnu99 which does not allow typedef redifitions. No functional change intended. Signed-off-by: David Matlack Link: https://lore.kernel.org/r/20251219233818.1965306-3-dmatlack@google.com Signed-off-by: Alex Williamson

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 ...

vfio: selftests: Add vfio_pci_device_init_perf_test

2025-11-28T17:58:07Z

Add a new VFIO selftest for measuring the time it takes to run vfio_pci_device_init() in parallel for one or more devices. This test serves as manual regression test for the performance improvement of commit e908f58b6beb ("vfio/pci: Separate SR-IOV VF dev_set"). For example, when running this test with 64 VFs under the same PF: Before: $ ./vfio_pci_device_init_perf_test -r vfio_pci_device_init_perf_test.iommufd.init 0000:1a:00.0 0000:1a:00.1 ... ... Wall time: 6.653234463s Min init time (per device): 0.101215344s Max init time (per device): 6.652755941s Avg init time (per device): 3.377609608s After: $ ./vfio_pci_device_init_perf_test -r vfio_pci_device_init_perf_test.iommufd.init 0000:1a:00.0 0000:1a:00.1 ... ... Wall time: 0.122978332s Min init time (per device): 0.108121915s Max init time (per device): 0.122762761s Avg init time (per device): 0.113816748s This test does not make any assertions about performance, since any such assertion is likely to be flaky due to system differences and random noise. However this test can be fed into automation to detect regressions, and can be used by developers in the future to measure performance optimizations. Suggested-by: Aaron Lewis Reviewed-by: Alex Mastro Tested-by: Alex Mastro Reviewed-by: Raghavendra Rao Ananta Signed-off-by: David Matlack Link: https://lore.kernel.org/r/20251126231733.3302983-19-dmatlack@google.com Signed-off-by: Alex Williamson

vfio: selftests: Eliminate INVALID_IOVA

2025-11-28T17:58:07Z

Eliminate INVALID_IOVA as there are platforms where UINT64_MAX is a valid iova. Reviewed-by: Alex Mastro Tested-by: Alex Mastro Reviewed-by: Raghavendra Rao Ananta Signed-off-by: David Matlack Link: https://lore.kernel.org/r/20251126231733.3302983-18-dmatlack@google.com Signed-off-by: Alex Williamson

vfio: selftests: Split libvfio.h into separate header files

2025-11-28T17:58:07Z

Split out the contents of libvfio.h into separate header files, but keep libvfio.h as the top-level include that all tests can use. Put all new header files into a libvfio/ subdirectory to avoid future name conflicts in include paths when libvfio is used by other selftests like KVM. No functional change intended. Reviewed-by: Alex Mastro Tested-by: Alex Mastro Reviewed-by: Raghavendra Rao Ananta Signed-off-by: David Matlack Link: https://lore.kernel.org/r/20251126231733.3302983-17-dmatlack@google.com Signed-off-by: Alex Williamson