kernel.git/tools/testing/selftests/x86, branch linux-6.15.y

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

2025-06-27T10:13:34Z

commit f287822688eeb44ae1cf6ac45701d965efc33218 upstream. 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 Signed-off-by: Greg Kroah-Hartman

selftest/x86/bugs: Add selftests for ITS

2025-05-09T20:39:45Z

Below are the tests added for Indirect Target Selection (ITS): - its_sysfs.py - Check if sysfs reflects the correct mitigation status for the mitigation selected via the kernel cmdline. - its_permutations.py - tests mitigation selection with cmdline permutations with other bugs like spectre_v2 and retbleed. - its_indirect_alignment.py - verifies that for addresses in .retpoline_sites section that belong to lower half of cacheline are patched to ITS-safe thunk. Typical output looks like below: Site 49: function symbol: __x64_sys_restart_syscall+0x1f <0xffffffffbb1509af> # vmlinux: 0xffffffff813509af: jmp 0xffffffff81f5a8e0 # kcore: 0xffffffffbb1509af: jmpq *%rax # ITS thunk NOT expected for site 49 # PASSED: Found *%rax # Site 50: function symbol: __resched_curr+0xb0 <0xffffffffbb181910> # vmlinux: 0xffffffff81381910: jmp 0xffffffff81f5a8e0 # kcore: 0xffffffffbb181910: jmp 0xffffffffc02000fc # ITS thunk expected for site 50 # PASSED: Found 0xffffffffc02000fc -> jmpq *%rax - its_ret_alignment.py - verifies that for addresses in .return_sites section that belong to lower half of cacheline are patched to its_return_thunk. Typical output looks like below: Site 97: function symbol: collect_event+0x48 <0xffffffffbb007f18> # vmlinux: 0xffffffff81207f18: jmp 0xffffffff81f5b500 # kcore: 0xffffffffbb007f18: jmp 0xffffffffbbd5b560 # PASSED: Found jmp 0xffffffffbbd5b560 # Site 98: function symbol: collect_event+0xa4 <0xffffffffbb007f74> # vmlinux: 0xffffffff81207f74: jmp 0xffffffff81f5b500 # kcore: 0xffffffffbb007f74: retq # PASSED: Found retq Some of these tests have dependency on tools like virtme-ng[1] and drgn[2]. When the dependencies are not met, the test will be skipped. [1] https://github.com/arighi/virtme-ng [2] https://github.com/osandov/drgn Co-developed-by: Tao Zhang Signed-off-by: Tao Zhang Signed-off-by: Pawan Gupta Signed-off-by: Dave Hansen

selftests: x86: test_mremap_vdso: skip if vdso is msealed

2025-04-01T22:17:15Z

Add code to detect if the vdso is memory sealed, skip the test if it is. Link: https://lkml.kernel.org/r/20250305021711.3867874-3-jeffxu@google.com Signed-off-by: Jeff Xu Reviewed-by: Kees Cook Reviewed-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Cc: Adhemerval Zanella Cc: Alexander Mikhalitsyn Cc: Alexey Dobriyan Cc: Andrei Vagin Cc: Anna-Maria Behnsen Cc: Ard Biesheuvel Cc: Benjamin Berg Cc: Christoph Hellwig Cc: Dave Hansen Cc: David Rientjes Cc: David S. Miller Cc: Elliot Hughes Cc: Florian Faineli Cc: Greg Ungerer Cc: Guenter Roeck Cc: Heiko Carstens Cc: Helge Deller Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com> Cc: Ingo Molnar Cc: Jann Horn Cc: Jason A. Donenfeld Cc: Johannes Berg Cc: Jorge Lucangeli Obes Cc: Linus Waleij Cc: Mark Rutland Cc: Matthew Wilcow (Oracle) Cc: Michael Ellerman Cc: Michal Hocko Cc: Miguel Ojeda Cc: Mike Rapoport Cc: Oleg Nesterov Cc: Pedro Falcato Cc: Peter Xu Cc: Randy Dunlap Cc: Stephen Röttger Cc: Thomas Weißschuh Cc: Vlastimil Babka Signed-off-by: Andrew Morton

Merge tag 'x86-cleanups-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-03-25T05:39:53Z

Pull x86 cleanups from Ingo Molnar: "Miscellaneous x86 cleanups by Arnd Bergmann, Charles Han, Mirsad Todorovac, Randy Dunlap, Thorsten Blum and Zhang Kunbo" * tag 'x86-cleanups-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/coco: Replace 'static const cc_mask' with the newly introduced cc_get_mask() function x86/delay: Fix inconsistent whitespace selftests/x86/syscall: Fix coccinelle WARNING recommending the use of ARRAY_SIZE() x86/platform: Fix missing declaration of 'x86_apple_machine' x86/irq: Fix missing declaration of 'io_apic_irqs' x86/usercopy: Fix kernel-doc func param name in clean_cache_range()'s description x86/apic: Use str_disabled_enabled() helper in print_ipi_mode()

Merge tag 'x86-fpu-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

2025-03-25T05:27:18Z

Pull x86/fpu updates from Ingo Molnar: - Improve crypto performance by making kernel-mode FPU reliably usable in softirqs ((Eric Biggers) - Fully optimize out WARN_ON_FPU() (Eric Biggers) - Initial steps to support Support Intel APX (Advanced Performance Extensions) (Chang S. Bae) - Fix KASAN for arch_dup_task_struct() (Benjamin Berg) - Refine and simplify the FPU magic number check during signal return (Chang S. Bae) - Fix inconsistencies in guest FPU xfeatures (Chao Gao, Stanislav Spassov) - selftests/x86/xstate: Introduce common code for testing extended states (Chang S. Bae) - Misc fixes and cleanups (Borislav Petkov, Colin Ian King, Uros Bizjak) * tag 'x86-fpu-2025-03-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: x86/fpu/xstate: Fix inconsistencies in guest FPU xfeatures x86/fpu: Clarify the "xa" symbolic name used in the XSTATE* macros x86/fpu: Use XSAVE{,OPT,C,S} and XRSTOR{,S} mnemonics in xstate.h x86/fpu: Improve crypto performance by making kernel-mode FPU reliably usable in softirqs x86/fpu/xstate: Simplify print_xstate_features() x86/fpu: Refine and simplify the magic number check during signal return selftests/x86/xstate: Fix spelling mistake "hader" -> "header" x86/fpu: Avoid copying dynamic FP state from init_task in arch_dup_task_struct() vmlinux.lds.h: Remove entry to place init_task onto init_stack selftests/x86/avx: Add AVX tests selftests/x86/xstate: Clarify supported xstates selftests/x86/xstate: Consolidate test invocations into a single entry selftests/x86/xstate: Introduce signal ABI test selftests/x86/xstate: Refactor ptrace ABI test selftests/x86/xstate: Refactor context switching test selftests/x86/xstate: Enumerate and name xstate components selftests/x86/xstate: Refactor XSAVE helpers for general use selftests/x86: Consolidate redundant signal helper functions x86/fpu: Fix guest FPU state buffer allocation size x86/fpu: Fully optimize out WARN_ON_FPU()

Merge branch 'x86/cpu' into x86/asm, to pick up dependent commits

2025-03-04T10:19:21Z

Signed-off-by: Ingo Molnar

selftests/x86/syscall: Fix coccinelle WARNING recommending the use of ARRAY_SIZE()

2025-03-03T11:38:49Z

Coccinelle gives WARNING recommending the use of ARRAY_SIZE() macro definition to improve the code readability: ./tools/testing/selftests/x86/syscall_numbering.c:316:35-36: WARNING: Use ARRAY_SIZE Fixes: 15c82d98a0f78 ("selftests/x86/syscall: Update and extend syscall_numbering_64") Signed-off-by: Mirsad Todorovac Signed-off-by: Ingo Molnar Reviewed-by: Muhammad Usama Anjum Link: https://lore.kernel.org/r/20241101111523.1293193-2-mtodorovac69@gmail.com

selftests/x86/xstate: Fix spelling mistake "hader" -> "header"

2025-02-27T09:49:31Z

There is a spelling mistake in a sig_print() message. Fix it. Signed-off-by: Colin Ian King Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20250227091533.599213-1-colin.i.king@gmail.com

selftests/x86/avx: Add AVX tests

2025-02-26T12:05:30Z

Add xstate testing specifically for those vector register states, validating kernel's context switching and ensuring ABI compliance. Use the established xstate testing framework. Alternatively, this invocation could be placed directly in xstate.c::main(). However, the current test file naming convention, which clearly specifies the tested area, seems reasonable. Adding avx.c considerably aligns with that convention. The test output should be like this for ZMM_Hi256 as an example: $ avx_64 ... [RUN] AVX-512 ZMM_Hi256: check context switches, 10 iterations, 5 threads. [OK] No incorrect case was found. [RUN] AVX-512 ZMM_Hi256: inject xstate via ptrace(). [OK] 'xfeatures' in SW reserved area was correctly written [OK] xstate was correctly updated. [RUN] AVX-512 ZMM_Hi256: load xstate and raise SIGUSR1 [OK] 'magic1' is valid [OK] 'xfeatures' in SW reserved area is valid [OK] 'xfeatures' in XSAVE header is valid [OK] xstate delivery was successful [OK] 'magic2' is valid [RUN] AVX-512 ZMM_Hi256: load new xstate from sighandler and check it after sigreturn [OK] xstate was restored correctly But systems without AVX-512 will look like: ... The kernel does not support feature number: 5 The kernel does not support feature number: 6 The kernel does not support feature number: 7 Signed-off-by: Chang S. Bae Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20250226010731.2456-10-chang.seok.bae@intel.com

selftests/x86/xstate: Clarify supported xstates

2025-02-26T12:05:30Z

The established xstate test code is designed to be generic, but certain xstates require special handling and cannot be tested without additional adjustments. Clarify which xstates are currently supported, and enforce testing only for them. Signed-off-by: Chang S. Bae Signed-off-by: Ingo Molnar Link: https://lore.kernel.org/r/20250226010731.2456-9-chang.seok.bae@intel.com