> diff --git a/tools/testing/selftests/bpf/usdt.h
> b/tools/testing/selftests/bpf/usdt.h
> index c71e21df38b3..75687f50f4e2 100644
> --- a/tools/testing/selftests/bpf/usdt.h
> +++ b/tools/testing/selftests/bpf/usdt.h
> @@ -313,7 +313,7 @@ struct usdt_sema { volatile unsigned short active; };
> #if defined(__ia64__) || defined(__s390__) || defined(__s390x__)
> #define USDT_NOP nop 0
> #elif defined(__x86_64__)
> -#define USDT_NOP .byte 0x90, 0x0f, 0x1f, 0x44, 0x00,
> 0x0 /* nop, nop5 */
> +#define USDT_NOP .byte 0x90, 0x66, 0x2e, 0x0f, 0x1f,
> 0x84, 0x00, 0x00, 0x00, 0x00, 0x00 /* nop, nop10 */
> #else
> #define USDT_NOP nop
> #endif
Does changing this instruction sequence from 6 bytes to 11 bytes break
prog_tests/usdt.c? The test in subtest_optimized_attach() searches for the
old 6-byte nop1_nop5_combo sequence:
tools/testing/selftests/bpf/prog_tests/usdt.c:
/* usdt_2 USDT probe has nop,nop5 instructions combo */
addr_2 = find_instr(usdt_2, nop1_nop5_combo, 6);
if (!ASSERT_OK_PTR(addr_2, "usdt_2_find_nop1_nop5_combo"))
goto cleanup;
Because the old sequence is no longer emitted by USDT_NOP, find_instr() will
return NULL, causing the ASSERT_OK_PTR assertion to fail. Should the test
update be squashed into this commit to avoid breaking git bisect?
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/26227520868
