wireguard-linux/tools/testing/selftests/x86, branch stable

selftests/x86: Check signal state for rejected software interrupts

2026-09-18T10:33:18Z

Add a test of the signal ABI for INT instructions in both 32-bit and 64-bit processes. Check the signal number, trap number, error code, si_code, si_addr, instruction pointer and RF/TF state against legacy IDT behavior. Include a 15-byte prefixed INT to check that IP uses the hardware instruction length. Exercise both INT3 encodings, INT4, UD2 and HLT to cover the unchanged trap and fault paths. Run each instruction with TF clear and set. Resume at a known NOP after handling the signal and check that single-stepping traps after the NOP. Also drive INT 0x2d under ptrace, which resumes through the fault frame rather than sigreturn and so exposes a stale FRED software event flag. Start from an INT3 stop, whose FRED frame has no software event flag, instead of the syscall frame of raise(SIGSTOP). Single-step into the INT and check that the fault reports its address. Then suppress SIGSEGV and resume at the NOP, once with PTRACE_SINGLESTEP and once with PTRACE_CONT and TF set. Section 6.2.3 of the Intel FRED specification [1] specifies the immediate single-step trap caused by returning with both that flag and TF set. Check that each trap occurs after the NOP, rather than at its address. Report whether the CPU supports FRED, since a pass looks the same on either entry path. INT 0x80 with IA32 emulation disabled and a 64-bit tracer of a 32-bit tracee are not covered. Both variants pass all 29 checks on a non-FRED AMD host and on Panther Lake with FRED enabled and the fix applied. With the same binaries on unpatched Panther Lake, 16 signal-context checks fail and the first ptrace check reports the IP after the INT. The two dependent ptrace resume checks are not reached. [1] Intel Flexible Return and Event Delivery (FRED) Specification, revision 9.0 (346446-009US), section 6.2.3. Signed-off-by: Matthew Schwartz Signed-off-by: Peter Zijlstra (Intel) Link: https://cdrdv2.intel.com/v1/dl/getContent/678938 # [1] Link: https://patch.msgid.link/20260917230907.2080792-3-matthew.schwartz@linux.dev

selftests/x86: Add shadow stack uprobe CALL test

2026-07-02T11:21:49Z

Add coverage for entry uprobes installed on CALL instructions while user shadow stack is enabled. The test puts an entry uprobe on a helper whose first instruction is a relative CALL, then verifies that the call/return sequence completes without SIGSEGV. This catches regressions where x86 uprobe CALL emulation updates the regular user stack but leaves the CET shadow stack stale. Signed-off-by: David Windsor Signed-off-by: Peter Zijlstra (Intel) Link: https://patch.msgid.link/b957039191118c5eba97d01d80c494b859f115a6.1782777969.git.dwindsor@gmail.com

selftests/x86: Clean up sysret_rip coding style

2026-01-19T11:06:11Z

Tidy up sysret_rip style (cast spacing, main(void), const placement). No functional change intended. Signed-off-by: UYeol Jo Signed-off-by: Borislav Petkov (AMD) Link: https://patch.msgid.link/20260111210126.74752-1-jouyeol8739@gmail.com

selftests/x86: Add selftests include path for kselftest.h after centralization

2026-01-17T11:22:27Z

The previous change centralizing kselftest.h include path in lib.mk caused x86 selftests to fail, as x86 Makefile overwrites CFLAGS using ":=", dropping the include path added in lib.mk. Therefore, helpers.h could not find kselftest.h during compilation. Fix this by adding the tools/testing/sefltest to CFLAGS in x86 Makefile. [ bp: Correct commit ID in Fixes: ] Fixes: e6fbd1759c9e ("selftests: complete kselftest include centralization") Closes: https://lore.kernel.org/lkml/CA+G9fYvKjQcCBMfXA-z2YuL2L+3Qd-pJjEUDX8PDdz2-EEQd=Q@mail.gmail.com/T/#m83fd330231287fc9d6c921155bee16c591db7360 Reported-by: Linux Kernel Functional Testing Signed-off-by: Bala-Vignesh-Reddy Signed-off-by: Borislav Petkov (AMD) Tested-by: Anders Roxell Tested-by: Brendan Jackman Link: https://patch.msgid.link/20251022062948.162852-1-reddybalavignesh9979@gmail.com

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

selftests/x86: Update the negative vsyscall tests to expect a #GP

2025-11-18T18:38:26Z

Some of the vsyscall selftests expect a #PF when vsyscalls are disabled. However, with LASS enabled, an invalid access results in a SIGSEGV due to a #GP instead of a #PF. One such negative test fails because it is expecting X86_PF_INSTR to be set. Update the failing test to expect either a #GP or a #PF. Also, update the printed messages to show the trap number (denoting the type of fault) instead of assuming a #PF. Signed-off-by: Sohil Mehta Signed-off-by: Dave Hansen Reviewed-by: Dave Hansen Link: https://patch.msgid.link/20251118182911.2983253-8-sohil.mehta%40intel.com

selftests/x86: Add a test to detect infinite SIGTRAP handler loop

2025-06-09T15:52:06Z

When FRED is enabled, if the Trap Flag (TF) is set without an external debugger attached, it can lead to an infinite loop in the SIGTRAP handler. To avoid this, the software event flag in the augmented SS must be cleared, ensuring that no single-step trap remains pending when ERETU completes. This test checks for that specific scenario—verifying whether the kernel correctly prevents an infinite SIGTRAP loop in this edge case when FRED is enabled. The test should _always_ pass with IDT event delivery, thus no need to disable the test even when FRED is not enabled. Signed-off-by: Xin Li (Intel) Signed-off-by: Dave Hansen Tested-by: Sohil Mehta Cc:stable@vger.kernel.org Link: https://lore.kernel.org/all/20250609084054.2083189-3-xin%40zytor.com

Merge commit 'its-for-linus-20250509-merge' into x86/core, to resolve conflicts

2025-05-13T08:47:10Z

Conflicts: Documentation/admin-guide/hw-vuln/index.rst arch/x86/include/asm/cpufeatures.h arch/x86/kernel/alternative.c arch/x86/kernel/cpu/bugs.c arch/x86/kernel/cpu/common.c drivers/base/cpu.c include/linux/cpu.h Signed-off-by: Ingo Molnar

Merge branch 'x86/mm' into x86/core, to resolve conflicts

2025-05-13T08:39:22Z

Conflicts: arch/x86/mm/numa.c arch/x86/mm/pgtable.c Signed-off-by: Ingo Molnar